,illustration3 ,the ,,rollo ,,books by ,,jacob ,,abbott4 ,,new ,,york3 ,t4 ,y4 ,,crowell ,,co4 ,illustration3 ,,so ,,he ,,took ,,up ,a ,,small ,,coal ,,of ,,fire4--,page #ig4 ,,rollo',s ,,philosophy4 ,,fire4 ,illustration ,,the ,,rollo ,,series ,,is ,,composed ,,of ,,fourteen ,,volumes1 ,,viz43 ,rollo ,learning to ,talk4 ,rollo ,learning to ,read4 ,rollo at ,work4 ,rollo at ,play4 ,rollo at ,school4 ,rollo's ,vacation4 ,rollo's ,experiments4 ,rollo's ,museum4 ,rollo's ,travels4 ,rollo's ,correspondence4 ,rollo's ,philosophy--,water4 ,rollo's ,philosophy--,air4 ,rollo's ,philosophy--,fire4 ,rollo's ,philosophy--,sky4 ,a ,,new ,,edition1 ,,revised ,,by ,,the ,,author4 ,illustration ,,new ,,york ,,thomas ,y4 ,,crowell ,,co4 ,,publishers ,entered1 according to ,act of ,congress1 in the year #ahee1 by ,,phillips1 ,,sampson ,,co41 ,in the ,clerk's ,office of the ,district ,court of the ,district of ,massachusetts4 ---------------------------------------- -------------------------------- ,,preface4 ,the main design in view1 in the discussions which are offered to the juvenile world1 under the title of ,,the ,,rollo ,,philosophy1 relates rather to their effect upon the little reader's habits of thinking1 reasoning1 and observation1 than to the additions they may make to his stock of knowledge4 ,the benefit which the author intends that the reader shall derive from them1 is an influence on the cast of his intellectual character1 which is receiving its permanent form during the years to which these writings are adapted4 ,the acquisition of knowledge1 however1 though in this case a secondary1 is by no means an unimportant object2 and the discussion of the several topics proceeds accordingly1 with regularity1 upon a certain system of classification4 ,this classification is based upon the more obvious external properties and relations of matter1 and less upon those1 which1 though they are more extensive and general in their nature1 and1 therefore1 more suitable1 in a strictly scientific point of view1 for the foundations of a system1 are less apparent1 and require higher powers of generalization and abstraction1 and are1 therefore1 less in accordance with the genius and spirit of the ,rollo philosophy4 ,as teachers have1 in some cases1 done the author the honor to introduce some of the preceding works of this class into their schools1 as reading books1 c41 considerable reference has been had to this1 in the form and manner of the discussion1 and questions have been added to facilitate the use of the books in cases where parents or teachers may make the reading of them a regular exercise of instruction4 ,,contents4 ,,chapter ,i4 ,page ,,slow ,,combustion #i ,,chapter ,,ii4 ,,lamp-,,lighting #ba ,,chapter ,,iii4 ,,burning ,,iron #cf ,,chapter ,,iv4 ,,fire ,,in ,,the ,,pasture #ed ,,chapter ,v4 ,,theory ,,and ,,practice #gj ,,chapter ,,vi4 ,,gunpowder #he ,,chapter ,,vii4 ,,the ,,alarm #ajb ,,chapter ,,viii4 ,,radiation ,,and ,,conduction #aaf ,,chapter ,,ix4 ,,radiation #acj ,,chapter ,x4 ,,condition #adb ,,chapter ,,xi4 ,,the ,,ride ,,home #aee ,,chapter ,,xii4 ,,the ,,conflagration #afe ,,the ,,rollo ,,philosophy4 ,,fire4 ,,chapter ,i4 ,,slow ,,combustion4 ,the way in which it happened that ,rollo's father first began to explain to him something about the nature of fire1 was this3 ,it was one evening early in the autumn4 ,dorothy was going away to visit one of her friends1 and ,rollo was waiting for ,jonas to come out1 and see the fire-flies1 or lightning-bugs1 as he called them1 which were flying about the yard4 ,but ,jonas did not come as soon as ,rollo had expected1 and so he went into the kitchen to see what had become of him4 ,he found that1 as ,dorothy was rather late for her visit1 and still had her kitchen fire to cover up1 ,jonas was just offering to cover it up for her1 so that she could go at once without any further delay4 ,so ,rollo came in1 and stood by the kitchen hearth to see ,jonas cover up the fire4 ,the fire had nearly burned out1 but it had left quite a large bed of embers1 and a few coals among them4 ,jonas took the long-handled iron shovel1 which belonged to the kitchen fire1 and with it he drew forward all these coals and embers1 so as to leave the back part of the hearth bare4 ,then he took the tongs1 and with the tongs he gathered out from the hot ashes all the coals which he could find among the ashes1 and put them back upon the bare place which he had made upon the hearth4 ,he spread them evenly over it in a row against the back of the chimney4 8,what are you going to do1 ,jonas80 said ,rollo4 8,i am going to cover up a stick of wood10 replied ,jonas4 ,so ,jonas opened a small door which led to a little wood closet by the side of the fire1 and took out a short stick of wood1 flat on one side and round on the other4 ,it was a stick which was round first1 but ,jonas had split it in two4 ,it was part of a great branch of a tree1 large enough to make a good log1 only ,jonas saw that it would split easily1 and so he had split it in two4 ,the other half of it was still in the wood closet4 8,this is just the stick10 said ,jonas4 8,why80 asked ,rollo4 8,why1 the lower side is flat10 said ,jonas1 8to lie upon the coals1 and the top is round1 so that ,i can cover it all up the easier40 ,so ,jonas laid the stick down1 with the flat side against the coals1 and the round side outwards4 ,then with the great shovel he began to shovel the ashes and embers back over it4 ,he put all the hot embers in first1 and then the ashes1 and he tried to cover up the stick entirely2 but there was not quite ashes enough4 ,one of the ends remained out4 8,there1 ,jonas10 said ,rollo1 8now come40 8,no10 said ,jonas1 8,i must cover the stick all up40 8,o1 that little end won't do any harm10 said ,rollo4 8,yes10 said ,jonas1 8because1 when the stick burns down1 that place would make a hole1 and let too much air in40 8,don't you want any air to get in80 said ,rollo4 8,very little10 said ,jonas4 8,i want a very slow combustion to go on until to-morrow morning1 and then there will be a good bed of coals for ,dorothy40 8,i don't see why you take so much pains to cover up a stick of wood10 said ,rollo4 8,you might light a fire with your tinder-box40 8,but it takes a great deal longer to make a good fire with a tinder-box1 than when we have a good bed of coals40 8,then take a friction match10 said ,rollo4 8,i can light a friction match in half a minute40 8,you can light the match1 but not build a fire4 ,it takes a long time with a match light to get heat enough to set large sticks of wood on fire2 but1 with a bed of burning coals1 we can do it very soon40 8,you might have some sticks and shavings for kindling10 said ,rollo1 8and they will burn quick40 8,yes10 said ,jonas1 8but it is more trouble to prepare sticks and shavings every night1 than it is to cover up a stick of wood40 ,while ,jonas had been saying these things1 he had taken more ashes from the ash-hole1 and had covered the stick over entirely4 ,he then put away the shovel1 and was brushing up the hearth1 when ,rollo1 after standing a moment1 as if in thought1 said1-- 8,jonas1 what do you mean by combustion80 8,did ,i say combustion80 rejoined ,jonas4 8,yes1 you said you wanted slow combustion40 8,well1 ,i meant burning4 ,i want the wood to burn slowly all night40 8,then why did not you say burning10 said ,rollo1 8so that ,i could understand you4 ,i don't see where you get all your learned words4 ,i suppose it is out of some of your books40 8,yes10 said ,jonas1 8they call it combustion in the books that ,i read1 but ,i don't know exactly why4 ,i think there must be some difference between combustion and burning1 but ,i don't know exactly what it is40 8,i mean to ask my father10 said ,rollo4 8,but do you expect that that stick of wood will burn1 ,jonas80 continued ,rollo1 after a moment's pause4 8,yes10 said ,jonas1 8it will burn slowly4 ,a little air will get through the ashes so as just to keep it burning slowly4 ,it is very dry40 8,suppose that there could not any air get through at all80 said ,rollo4 8,why1 then10 said ,jonas1 8it couldn't burn at all4 ,it would go out4 ,sometimes ,i have buried up a fire so deep in ashes that it has gone out1 and then ,i find nothing but black coals there in the morning1 when ,i rake it open4 ,that's the way they make charcoal40 8,how80 said ,rollo4 ,but ,jonas had no opportunity to answer this question then1 for they were just going out into the yard when ,rollo asked it1 and the attention of both the boys was attracted to the fire-flies4 ,they1 however1 soon had looked at the fire-flies as much as they wished4 ,rollo tried to catch one1 but he could not4 ,he would see a flash at a little distance from him1 and he would run to the place with his cap in the air2 but1 by the time that he got there1 the fire-fly would of course have gone on to another place1 though ,rollo could not tell where1 without waiting to see him flash again4 ,then he had to run again2 but before he got to this second place the fire-fly would be gone again4 ,one of the fire-flies led him a zigzag chase1 in this way1 all around the yard1 and finally flashed at last just over the garden fence1 so that ,rollo gave up in despair4 ,in the meantime1 ,jonas had gone to the barn2 and now ,rollo went to see what had become of him4 ,he found him shutting the doors up for the night1 and then they both came back towards the house1 and sat down upon the edge of the platform1 under the piazza1 and ,rollo asked ,jonas to tell him how they made charcoal4 8,why1 they only bury up wood1 as ,i did my log1 lightly1 so that enough air can get in1 until it is burnt through2 and then they cover it up tight1 so that no air can get in1 and so it goes out2 and when it is all cold1 they open it1 and find the heap is all black coals40 8,how big a heap do they make80 asked ,rollo4 8,o1 they make a very large heap1 sometimes10 said ,jonas2 8as big as this40 ,so ,jonas rose from his seat1 and marked out a circle in the yard with a stick1 which he had in his hand1 in order to show ,rollo how large a heap they make1 when they pile up wood for a charcoal bed4 8,and how high do they make it80 asked ,rollo4 8,as high as that0 said ,jonas2 and he reached his stick up in the air as high as he could1 to show ,rollo how high the heap was4 8,that must take a great deal of wood10 said ,rollo4 8,yes10 said ,jonas1 8and when it is turned into charcoal1 they get a great many loads of it40 8,how do they get ashes enough to cover it up80 asked ,rollo4 8,o1 they don't cover it with ashes10 said ,jonas2 8they cover it with turf40 8,with turf80 repeated ,rollo4 8,yes10 said ,jonas1 8turf is the best thing to cover the heap with4 ,if they had ashes1 it would be very troublesome to put it on1 and then it would be sliding down1 and letting the fire break out4 ,but they cut square pieces of turf1 and cover the heap all over with them1 very tight1 and so only just air enough gets in to keep the fire slowly burning40 8,slow combustion80 said ,rollo4 8,yes1 slow combustion10 said ,jonas4 8,how do you set it on fire80 asked ,rollo4 8,i believe they leave a hole in the middle10 said ,jonas1 8from the top down to the bottom1 and then they put the fire down there40 8,i wonder if ,i couldn't make a charcoal bed10 said ,rollo4 8,yes10 replied ,jonas1 8you might make a little one1 ,i suppose40 8,how should ,i do it80 asked ,rollo4 8,why1 you might take some dry wood from the shed1 and wheel it down the lane1 and through the gate into the pasture4 ,then you might take a spade1 and cut up some turf1 though that would be rather hard work for you40 8,i wish you would cut the turf for me10 said ,rollo4 8,well10 said ,jonas1 8perhaps ,i will4 ,then you must hollow out a little place in the bare spot ,i make by taking up the turf1 and make your pile of wood there1 leaving a hole in the middle40 8,how can ,i leave a hole80 asked ,rollo4 8,why1 you can take three short pieces of board1 as long as you intend the height of your pile to be1 and stand them up on the ground1 so as to leave a three-cornered space between them1 and then pile your wood around the three boards40 8,so ,i can10 said ,rollo4 8,your wood must be small10 continued ,jonas1 8or else you can't pile it very snugly in a small pile4 ,you had better take small round sticks1 and saw them short1 and lean them up against your boards all around1 and so make a snug pile4 ,after the pile is ready1 you must bank up a little against the bottom of your heap with the loose earth1 and then begin to put on the turf4 ,but that will be a nice business40 8,why80 asked ,rollo4 8,because you must fit them carefully all around2 and1 as the heap will be round1 and will grow smaller towards the top1 square pieces of turf will not fit4 ,you will have to cut them into shape with a knife4 ,you can get an old knife to cut them with1 and so fit them together4 ,but you must fit them together well1 or the air will get in1 and your heap of wood will blaze up1 and so it will be spoiled for charcoal40 8,i can make it tight10 said ,rollo1 8,i know4 ,i'll shave away the sides of every turf1 till it fits its place exactly40 8,there must be some air10 said ,jonas1 8or else the wood will not burn at all4 ,you must leave a few holes around at the bottom1 to let a little air in1 then you can plug some of them up1 if you find the fire burns too fast40 8,well10 said ,rollo1 8,i mean to make some charcoal some day4 ,i'll get my cousin ,james to come and help me4 ,i'll begin to saw up some wood for it to-morrow4 8,but1 then1 ,jonas10 he continued1 after a moment's pause1 8what good will the charcoal do me when ,i get it made80 8,o1 ,i don't know10 said ,jonas2 8,i wasn't thinking of your getting any good from the charcoal4 ,all the advantage would be1 the pleasure of making it40 8,isn't there anything ,i can do with it10 said ,rollo1 8when ,i get it made8 ,what is charcoal good for80 8,it makes a very hot fire4 ,they use it when they want a great heat4 ,blacksmiths use it in their forges40 8,i wish ,i had a little forge10 said ,rollo4 8,they use it to make gunpowder1 too10 said ,jonas4 8,how80 said ,rollo4 8,why1 they take some charcoal1 and some sulphur1 and some saltpetre1 and pound it up together1 and it makes gunpowder40 8,that's what ,i'll do with my charcoal10 said ,rollo1 jumping up from his seat4 8,i'll make some gunpowder4 ,i'll ask my mother to give me some sulphur and saltpetre1 and ,i'll make some gunpowder40 ,,questions4 ,what was the condition of the fire1 on the evening when it was left to ,jonas to cover up8 ,describe the arrangements which he made for covering up the fire4 ,what was the shape of the stick of wood8 ,why was this form convenient for the purpose8 ,what plan did ,rollo propose1 instead of covering up the fire8 ,what objection did ,jonas make to this plan8 ,what term did ,jonas use to designate the process which would go forward1 during the night1 under the ashes8 ,what did he say that combustion meant8 ,would any air at all be necessary for the slow combustion8 ,how was the necessary air to get access to the wood8 ,why could not ,rollo catch the fire-flies8 ,how did ,jonas describe the process of making charcoal8 ,what did he say were the uses of charcoal8 ,to which of these uses did ,rollo intend to put his charcoal1 if he should succeed in making any8 ,,chapter ,,ii4 ,,lamp-,,lighting4 ,rollo did not think to ask his father the reason why the philosophers use such learned language1 or1 as he expressed it1 such hard words1 for several days4 ,perhaps he never would have thought of it again1 if his father had not happened to use the word combustible one evening1 which reminded him of the term combustion1 which ,jonas had used4 ,the occasion on which his father used the word was this1-- ,one evening1 ,rollo's mother was trying to light a little lamp1 to go into her bedroom for something that she wanted4 ,there were1 usually1 in a little vase upon the mantel-piece1 some lamp-lighters1 which were long1 slender rolls of paper1 that ,rollo had rolled up for this purpose4 ,they were kept in this vase upon the mantel-piece in order to be always ready for use4 ,but the vase was now empty4 ,the last lamp-lighter had been used2 and so ,rollo's mother folded up a small piece of paper1 and attempted to light the little lamp1 which she was going to carry into the bedroom1 with that4 ,but the wick would not take fire1 and ,rollo saw that1 while his mother was continuing her efforts to make it burn1 the flame of the paper was gradually creeping up nearer and nearer to her fingers4 ,at last1 finding that there would soon be danger of burning her fingers1 she walked across the room towards a window which was open1 still endeavoring to light the lamp4 ,but it was all in vain4 ,she reached the window just in time to throw the end of the paper out1 and save her fingers from being burned4 8,why won't it light80 said ,rollo4 ,rollo's father was sitting upon the sofa1 taking his rest after the labors of the day2 and when he saw that the lamp failed of being lighted1 he said1-- 8,you will have to get a longer lamp-lighter1 unless you have got some spirits of turpentine to put upon the wick40 8,spirits of turpentine80 repeated ,rollo4 8,yes10 said his father4 8,in hotels1 where they have a great many lamps to light1 they have a little bottle of spirits of turpentine with a wire running down into it2 and1 when they take out the wire1 a little drop of the spirits of turpentine hangs to the end of it1 and they touch this to the wick1 and then it will light very quick40 8,why1 sir80 asked ,rollo4 8,because spirits of turpentine is very combustible1 or rather inflammable40 8,that means it will burn very easily1 ,i suppose10 said ,rollo4 8,yes10 replied his father4 8,that makes me think of something ,jonas said1 which ,i was going to ask you10 said ,rollo4 8,he said that1 in books1 burning was always called combustion1 and ,i told him ,i meant to ask you why they couldn't as well call it burning40 8,i don't think that ,jonas said exactly that10 said his father4 8,yes1 sir1 he did10 replied ,rollo2 8at least1 ,i understood him so40 8,it is true1 no doubt10 added his father1 8that1 in philosophical books1 philosophical terms are very often used1 instead of the common language which we ordinarily employ40 8,why are they1 father80 said ,rollo4 8,i think the common words are a great deal easier to understand40 8,yes10 said his father1 8but they are not precise in their signification4 ,they are vague and ambiguous1 and so philosophers1 when they wish to speak accurately1 employ other terms1 which have an exact signification40 ,rollo looked perplexed4 ,he did not understand at all what his father meant4 ,in the meantime1 his mother had brought a fresh bundle of lamp-lighters from the closet1 and had lighted her lamp with one of them1 and was just going away4 ,as she was going out1 however1 she said to her husband1-- 8,please to wait a minute1 until ,i come back1 for ,i should like to hear what you are going to say40 8,well10 said he2 8and you1 ,rollo1 may come and sit down by me1 and ,i will explain it to you when mother comes back40 ,so ,rollo came and took a seat on the sofa by the side of his father1 saying1-- 8,father1 ,i wish you would have a bottle of spirits of turpentine for us to light our lamps by40 8,it is not of much advantage in a family10 said his father1 8where the lamps are lighted in various parts of the house1 and only a few in all to be lighted4 ,but where there are a great many1 it is quite a saving of time to have a little spirits of turpentine to tip the wicks with4 ,in an illumination they always touch the wicks so1 and by that means they can light up suddenly40 8,but1 father1 why will the wick light any quicker80 8,why1 different substances take fire at different temperatures4 ,for instance1 if you were to put a little heap of sulphur1 and another little heap of sawdust1 on a shovel together1 and put them over a fire1 so as to heat them both equally1 the sulphur would take fire very soon1 but the sawdust would not until the shovel was very nearly red hot4 ,so if you were to put oil in a little kettle over the fire1 and spirits of turpentine in another kettle1 and have the fire the same under both1 the spirits of turpentine would inflame long before the oil4 ,there is a great difference in different substances1 in regard to the temperature at which they inflame40 8,what do you mean by temperature1 father80 said ,rollo4 8,why1 heat10 said his father4 8,then why don't you say heat80 said ,rollo4 ,his father laughed4 8,what are you laughing at1 father80 said ,rollo4 8,why1 that's the same question that you asked me at first1 and ,i promised to wait till mother came before ,i explained it4 ,so we will wait until she comes40 ,they did not have to wait long1 for ,rollo's mother soon returned2 and she put out her lamp by means of a little extinguisher which was attached to the stem of the lamp itself4 ,then she sat down at the table1 by the light of a great lamp which was burning upon it1 and took out her work4 ,rollo's father then repeated to her what he had just been telling ,rollo1 namely1 that different substances took fire at different degrees of heat2 and he said that it would be a very interesting experiment to take a long iron bar1 and put a small quantity of several different substances upon it1 in a row1 and then heat the bar gradually1 from end to end all alike1 until it was very hot1 and so see in what order the various substances would take fire4 8,i would have10 said he1 8phosphorus1 sulphur1 sawdust1 charcoal1 saltpetre1 oil1--we should have to make a little hollow in the iron for the oil1--alcohol1 spirits of turpentine1 and perhaps other things4 ,the phosphorus would take fire first1 ,i suppose1 and then perhaps the sulphur1 and others in succession40 8,well1 father10 said ,rollo1 8,i wish you would4 ,i should like to see the experiment very much40 8,no10 said his father1 8,i cannot actually try such an experiment as that4 ,i could not get such a bar very conveniently2 and1 if ,i had the bar and all the substances1 ,i could not heat the bar exactly equally4 ,it could not be done very well1 except in a chemical laboratory4 ,but it would be a very pretty experiment1 if it could be performed40 8,is there a very great difference10 said ,rollo's mother1 8in the degree of heat necessary to set fire to these different things80 8,yes10 said ,mr4 ,holiday1 8,i believe the difference is very great4 ,phosphorus inflames below the heat of boiling water1 but it takes almost a red heat to set wood on fire4 ,and iron will not take fire till it is white hot40 8,iron80 said ,rollo1 with surprise4 8,yes10 said his father1 8iron will take fire and burn as well as wood1 if you heat it hot enough40 8,i never knew that10 said ,rollo4 8,the ends of the tongs and of the andirons do not burn10 said his father1 8simply because the fire is never hot enough to set such a large piece of iron on fire4 ,but if we heat the end of a bar of iron very hot indeed in a furnace1 it will take fire and burn2 and so1 if we take a very minute piece of iron1 as big as the point of a pin1 a common fire would be sufficient to heat that hot enough to set it on fire40 8,well1 father10 said ,rollo1 8let us try it40 8,if we had some iron filings1 we might sprinkle them in the fire1 or even in the flame of a lamp1 and they would burn40 8,i wish ,i had some filings10 said ,rollo4 8,yes10 said his father1 8they burn beautifully40 8,how can ,i get some80 asked ,rollo4 8,you can get some at a blacksmith's shop10 said his father4 8,the filings commonly accumulate behind the vice1 and you can get plenty of them there4 ,the next time you go by a blacksmith's shop1 you had better go in and ask him to give you some40 8,well10 said ,rollo1 8so ,i will40 8,and now do you understand10 said his father1 8why it is that you can light a lamp more easily when there is a little spirits of turpentine on the wick80 8,yes1 sir10 said ,rollo4 8,the spirits of turpentine need not get so hot before it catches fire1 and so you don't have to hold the lamp-lighter so long1 and burn your fingers40 8,will oil always take fire when it gets to a certain degree of heat80 asked ,rollo's mother4 8,yes10 said his father1 8,i suppose so40 8,and yet10 said she1 8the lamp seems to take fire much more easily at some times1 than at others40 8,yes10 said ,mr4 ,holiday1 8that is true4 ,if the wick is cut square across1 and rises up only a very little way above the tube1 it is very difficult to light it1 because the tube itself and the oil below keep the upper end of the wick cool4 ,it is very hard to heat it1 in that case1 hot enough to set it on fire4 ,but if the wick projects considerably out of the tube1 then it is out of the way of the cooling influence of the metal1 and you can heat the upper end more easily40 8,i never thought of that10 said ,rollo4 8,that is the operation of it10 said his father4 8,and if you push the wick open a little1 so as to separate some of the fibres of it from the rest1 then it will take fire more easily still2 because the small part which is separated1 is more easily heated up to the necessary point1 than it was when it was closely in contact with the rest1 and so kept cool by it4 ,that is the reason why a thin shaving takes fire so much more easily than the outside of a large piece of wood4 ,the outside of a large piece is kept cool by the parts of the wood behind it1 which touch it1 while the shaving is heated through very soon40 8,i didn't know that before10 said ,rollo4 8,in the cities10 continued his father1 8the lamp-lighters1 that trim and light the street lamps1 always cut the wick off1 when they trim the lamps1 in a slanting direction1 so as to leave a point of the wick projecting up on one side4 ,this point will light very easily1 for it stands by itself1 somewhat apart from the rest1 and so is not kept cool by the rest of the wick4 ,then1 when they put in their great1 blazing torch1 it heats this point to the degree necessary to inflame the oil very easily4 8,there is one thing more ,i want to tell you1 and that will be all ,i have to say about lamps to-night2 and that is1 to explain to you the philosophy of putting them out4 ,you must understand that two things are necessary to carry on combustion or burning4 ,first1 there must be air2 and secondly1 the body burning must be kept above a certain degree of heat4 ,now1 if you either suddenly shut off the air from the substance that is burning1 or suddenly cool the substance1 it will go out4 ,for instance1 the wick1--you have to heat it to a certain degree before it will take fire4 ,now1 if1 after it is burning1 you suddenly cool it below that degree1 it will go out2 or if you shut out the air from it1 then it will go out2 for it cannot burn unless it continues hot1 and unless it continues to have a supply of air4 8,now1 when we blow out a lamp1 we stop the burning by cooling it4 ,the cool air which we blow against it1 suddenly cools the upper end of the wick below the point of combustion1 and so it goes out4 ,on the other hand1 when we put it out by an extinguisher1 we stop the burning by means of shutting out the air4 ,either mode will stop the combustion40 8,and how is it when we put on water80 asked ,rollo's mother4 8,why1 that is somewhat different from either10 said ,mr4 ,holiday1 8or rather it is both combined4 ,there is something very curious in the operation of water upon fire2 that ,i must explain some other day1 for now it is time for ,rollo to go to bed40 ,,questions4 ,what was the difficulty in lighting the lamp1 as described in the beginning of this chapter8 ,what method did ,mr4 ,holiday say was sometimes adopted in hotels to make the lamps light quick8 ,why would this make them light more easily8 ,what question did ,rollo ask his father in respect to the use of philosophical language8 ,why did not his father answer the question immediately8 ,do all substances take fire at the same temperature8 ,what substances take fire with the least degree of heat8 ,what experiment did ,mr4 ,holiday describe which he said would show this very distinctly8 ,why could not he perform this experiment8 ,will iron burn8 ,why do not bars of iron burn in a common fire8 ,how did ,mr4 ,holiday propose to show that iron would burn8 ,how did he propose that ,rollo should get some iron filings8 ,,chapter ,,iii4 ,,burning ,,iron4 ,when ,rollo went out into the kitchen that evening to get his safety lamp1--the one which he usually took to go to bed1--he found ,jonas sitting at the kitchen table reading2 and while he was lighting his lamp1 he asked ,jonas if he would not get him some iron filings the next time he went near any blacksmith's shop4 ,jonas asked him what he wanted of iron filings1 and he said he wanted them to burn4 ,he then repeated to him what his father had said in respect to the combustibility of iron4 8,i can make iron filings enough for that experiment in five minutes10 said ,jonas4 8,how80 said ,rollo4 8,with a file10 replied ,jonas4 8,well10 said ,rollo2 and without waiting to hear anything further1 he ran back to the parlor to ask his mother to let him sit up long enough to see ,jonas make a few iron filings to try the experiment4 8,won't it do as well to-morrow morning80 asked his mother4 8,the scintillations will look brighter in the evening10 said ,mr4 ,holiday4 8,very well1 then10 added his mother1 8go1 and1 if ,jonas succeeds in his experiment1 ask him to send some filings in to us40 ,so ,rollo went out to find ,jonas again4 ,jonas was gone4 ,dorothy said that he had gone after a file4 ,in a few minutes he returned1 with a file in one hand1 and a large iron spike in the other4 8,what is the spike for80 asked ,rollo4 8,only for a piece of iron to file10 replied ,jonas4 ,so saying1 he took a small piece of paper out of a drawer1 and laid it upon the table4 ,then he rested one end of the spike upon the paper1 and1 holding the other end in his hand1 he filed it several times in such a way1 that the filings fell down upon the paper4 8,what fine filings60 said ,rollo4 8,yes10 said ,jonas2 8the file is almost worn out1 and it does not cut very well40 ,rollo looked upon the paper4 ,there were quite a number of small1 black points upon it like grains of very fine sand4 ,jonas then took up the paper carefully by the two sides1 bending the two sides upward at the same time1 to keep the filings in the middle of the paper4 ,in this way he raised the paper above the lamp1 which was upon the table before him1 and then holding it in an inclined position1 he let the sand slide down into the flame of the lamp4 ,to ,rollo's surprise and delight1 it produced a column of sparkles rising up from the flame1 which were of the greatest brilliancy and beauty4 8,yes10 said ,rollo1 8they burn1 they burn most beautifully4 ,file me some more1 ,jonas1 and let me carry them in and show them to my mother40 ,jonas accordingly filed some more filings1 and ,rollo went in with them very eagerly1 to show to his mother4 8,just look10 said ,rollo2 and so saying1 he held the paper over the lamp in such a manner as to let the filings slide down into the flame just as ,jonas had done4 ,the experiment succeeded perfectly well1 as it had done before4 8,so you see that it will burn10 said ,mr4 ,holiday1 8if you heat it hot enough40 8,if you make it small enough1 you mean10 said ,rollo4 8,i suppose the smallness of the particles is of no consequence10 replied his father1 8excepting to make it easier to heat them40 8,why1 father10 said ,rollo1 8,i might put the end of a knitting-needle in the lamp1 and ,i don't see why it wouldn't become as hot as one of the iron filings40 8,because10 said his father1 8a part of the heat would be conveyed away through the knitting-needle towards your hand1 and that would keep the end which was in the flame cooler40 8,would it1 sir10 asked ,rollo4 8,yes10 said his father4 8,the heat moves off very fast in such a case4 ,you know1 if you take a pin between your fingers1 and hold the head of it in the lamp1 the heat will almost immediately move along the metal1 so as to heat the end that you are holding1 and burn you40 8,yes1 sir10 said ,rollo2 8,i have got burned so1 very often40 8,and of course much more heat would be conveyed away when the metal was as thick as a knitting-needle40 8,well1 father10 said ,rollo1 8suppose a piece of the knitting-needle was broken off1 and made so small that it could all be in the flame2 then would it burn80 8,how could you keep it there80 asked his father4 8,why--,i don't know10 said ,rollo1 hesitating4 8,couldn't we contrive some way to keep it there80 8,i don't know of any way40 8,couldn't we put it on the end of the wick80 asked ,rollo4 8,yes10 said his father1 8perhaps we might2 but then the end of the wick is cool1 and that would cool it40 8,o1 father10 said ,rollo1 in a tone of great surprise1 8the end of the wick cool1 when it is right in the middle of the blaze60 8,i mean10 replied his father1 8that it is cool compared with the heat necessary for inflaming the iron4 ,it would feel very hot to your fingers1 ,i have no doubt1 for it is filled with boiling oil4 ,but then even the heat of boiling oil is less than that necessary to inflame iron2 and so the contact of the wick with such a piece of iron as you propose1 would keep it cool1 or rather keep it from getting hot enough to take fire40 8,suppose there was any way10 said ,rollo's mother1 8of suspending a piece of iron as large as the end of a knitting-needle in the lamp2 do you think it would take fire80 8,no10 said ,mr4 ,holiday1 8,i don't think it would be heated hot enough4 ,for some reason or other1 ,i don't understand exactly what1 a large piece of iron cannot be heated very hot in a small fire1 even if the fire entirely covers it4 ,i don't think that any fragment of iron much larger than one of ,jonas's filings could be heated in a lamp so as to take fire4 ,but it could be heated hot enough in a forge4 ,the end of the iron which a blacksmith heats is often in a state of combustion when he takes it out of the fire40 8,there1 now1 father10 said ,rollo1 8you have not explained to me yet about combustion and burning40 8,no10 said his father2 8we had almost forgotten that4 ,i will explain it now4 ,it will only take a few minutes4 ,let me see--,i began to tell you didn't ,i80 8,yes1 sir10 said ,rollo2 8but ,i couldn't understand very well40 8,i was telling you that the language which we use in common conversation is not precise4 ,it is often ambiguous40 8,what does that mean1 sir80 said ,rollo4 8,why1 language is ambiguous when it has two meanings10 said his father4 8,for instance1 the word burning is used in conversation to express two or three very different things4 ,if you put your finger upon hot iron1 you say you have burned it4 ,burn1 in that case1 is the name of a painful feeling4 ,but if you say you burned a piece of paper1 you mean that you put it into the fire1 and allowed it to be consumed4 ,in that case1 burning1 instead of being the name of a painful feeling1 is the name of a peculiar process by which the paper is consumed and destroyed4 ,thus the word burn is used to denote two very different effects4 ,in fact1 it is used in other senses besides these40 8,what others1 sir80 asked ,rollo4 8,why1 when we say that a little girl was out in the sun1 and burned her face and neck1 we do not mean that her face and neck were consumed1 or that they felt a painful sensation1--but that the skin was reddened by the sun's heat4 ,so1 when we say that the grass was all burned up in the drought1 we mean that it was dried and withered4 ,thus burned and burning are used to denote a great variety of effects produced by heat1 which effects are very different from each other in their nature4 ,so that1 you see1 when we are going to speak philosophically of that peculiar process by which bodies are actually consumed by fire1 it becomes necessary to have some term to denote that process alone1 and not all the other kinds of burning4 ,now1 the word the philosophers use for this purpose is combustion4 ,the burning of a stick of wood upon the fire is combustion1 but the burning of your finger against a hot iron is not combustion1 and the burning of bricks in a brick kiln is not combustion40 8,nor the burning of the grass in the drought10 said ,rollo4 8,no10 said his father4 8,thus you see that combustion is a term of precise and definite meaning2 it denotes a particular process1 and that alone4 ,but burning is a vague and ambiguous term2 it has a great many meanings1 or1 rather1 it stands for a great many different effects1 very much unlike in their character4 ,in fact1 they seem to be alike in no respect1 except that they are all produced by heat40 8,yes1 father10 said ,rollo1 8,i understand40 8,sometimes10 added his father1 8the word used in common life doesn't mean enough1 instead of meaning too much4 ,for example1 there is the word freeze4 ,what is the meaning of the word freeze80 8,why1 it means10 said ,rollo1--8freeze8--it means--water turning into ice40 8,yes10 replied his father2 8when water is cooled below a certain point1 it becomes solid4 ,it is just so with lead4 ,melted lead1 when it is cooled below a certain point1 becomes solid4 ,the hardening of the melted lead into solid lead1 and the hardening of water into ice1 as they cool1 seem to be phenomena of precisely the same character1 and yet the word freeze applies only to one4 ,we say the water freezes1 but we can't say the lead freezes40 8,why not1 sir80 asked ,rollo4 8,because it is not the customary use of the word4 ,if we use the terms of common life1 we must use them as they are customarily used1 or we shall not be understood4 ,freezing1 therefore1 will not answer to express all cases of the hardening of a liquid by cold1 because that is a term which is only applied to a few of the cases4 ,now1 philosophers want a term which will apply to all the cases of the same kind40 8,and what is their word80 asked ,rollo4 8,congelation10 replied his father4 8,congelation80 repeated ,rollo4 8,yes10 said his father4 8,when water becomes ice1 the philosophers say it congeals4 ,so when lead hardens in cooling1 they say it congeals4 ,different substances congeal at very different degrees of heat4 ,if we had melted iron and melted lead1 equally hot1 and let them cool together1 the iron would congeal first2 and if they continued cooling1 by and by the lead would congeal4 ,water would remain liquid long after lead would congeal2 but if it was placed where it would grow colder and colder1 the temperature would at last reach the point where water would congeal too4 ,but whatever the liquid is1 and whatever the point is at which it changes from a liquid to a solid form1 it is called congealing40 8,and the word freezing1 then1 is only used in respect to water10 said ,rollo's mother4 8,why1 yes10 said ,mr4 ,holiday2 8we speak of other things freezing beside water2 but it is only such things as become solid under great degrees of cold4 ,we say ink freezes1 and oil1 and if it were cold enough to freeze brandy1 or mercury1 we should say they were frozen4 ,but substances that harden when they are not very cold1 as lead or wax1 are not said to freeze40 8,thus you observe10 continued ,rollo's father1 8in common language words are not used in a precise and definite manner4 ,their meaning is determined by the outward and visible effects that we see1 and not by the real nature of the causes4 ,thus a great many different effects are called burning1 in common language1 because they are all effects produced in various ways by heat4 ,but the terms used by philosophers are definite and precise1 each one being confined to one specific process or phenomenon40 8,father10 said ,rollo1 8,i want to see the iron filings burn again1 and ,i am going out to ask ,jonas to file a few more40 8,very well10 said his father4 ,so ,rollo went out to get ,jonas to make him some more filings1 and ,jonas did so4 ,presently ,rollo returned bringing the paper in very carefully1 with the filings upon it4 ,he put them down upon the table1 and his father contrived1 by bending the paper in different directions1 to gather all the filings together into the middle of it1 and then1 with the point of his penknife1 he took up a few of the filings at a time1 and let them drop upon the flame of the lamp4 ,the burning of the filings produced1 as before1 the most brilliant scintillations4 8,what bright sparkles60 said ,rollo4 8,yes1 it is very inflammable indeed10 said his mother4 ,here ,mr4 ,holiday dropped more filings upon the flame1 from the point of his knife4 8,does inflammable mean10 continued his mother1 8that a thing takes fire easily1 or that it burns with a great flame when it does take fire80 8,i don't know10 said ,mr4 ,holiday2 8,i never thought of that distinction4 ,some things take fire very easily1 but don't make a great flame4 ,there's sulphur1 for instance2 it takes fire before it gets very hot1 but it burns with a very small and faint flame40 8,let us try it1 father10 said ,rollo4 8,we can't try it very well1 because there is no fire4 ,i suppose the fire in the kitchen is covered up4 ,but if there was a fire1 and we were to put a little sulphur upon a shovel1 and a small piece of paper by the side of it1 and hold them over the fire1 we should find that the sulphur would take fire before the paper would even begin to be scorched2 but it would make only a very small blue flame4 ,the paper would not take fire nearly as easily2 but we should find that when it did take fire1 it would make a much larger and brighter flame40 8,i wish you would try it1 father10 said ,rollo2 8you can uncover the coals in the kitchen1 and find fire enough40 8,well10 said his father1 8,i will40 ,his father accordingly rose from his seat1 and asked ,rollo to go into the kitchen1 and get the shovel1 and bring it to the medicine closet4 ,while ,rollo was getting the shovel1 his father went to the closet1 and took down a little jar half filled with sulphur4 ,when ,rollo brought him the shovel1 he took out a little of the sulphur upon the point of his knife1 and laid it upon the shovel4 ,he also took a small piece of paper1 and laid it upon the shovel by the side of the sulphur4 ,rollo then led the way to the kitchen1 followed by his father with the shovel1 and his mother came behind4 ,they opened the coals a little1 and placed the shovel upon them4 ,jonas and ,dorothy looked on with great interest1 wondering what they were going to do4 ,the sulphur began to melt almost immediately after the shovel was placed upon the coals2 and1 in a very short time1 ,rollo observed a faint blue spot on the place where the sulphur had been lying4 8,there10 said his father1 8see what a small flame40 8,yes10 said ,rollo2 8it is nothing but a little blue spot40 8,and the paper is just as whole and white as ever it was40 8,let us wait till the paper gets hot enough to burn40 8,i don't think it would ever get hot enough to burn10 replied his father1 8over such a fire as that4 ,i must light it in the lamp40 ,so he waited a few minutes until the sulphur was entirely consumed1 for he said that he did not wish to have any of the fumes get into the room2 and then he dropped the paper off from the shovel down upon the hearth1 and ,rollo picked it up4 ,his father lighted it in the lamp1 and then placed it upon the shovel to see it burn1 in order that ,rollo might compare the magnitude of the flame which was produced with that of the sulphur4 ,of course1 such a small piece of paper did not make a large flame1 but it was four or five times as large as that produced by the sulphur4 8,now the question is10 said ,mr4 ,holiday1 8which is most inflammable1--the sulphur1 because it inflames most easily1 or the paper1 because it makes the greatest flame when it does take fire80 8,i should think the paper10 said ,rollo4 8,there is alcohol10 said ,mr4 ,holiday1 8which takes fire very easily1 but it burns with a very pale and light flame4 ,oil must be heated much hotter before it will burn2 but1 when it does burn1 it gives a large and bright flame2 so that oil is good for lamps1 it gives so much light when it burns4 8,spirits of turpentine10 continued ,mr4 ,holiday1 8inflames easily1 and burns brightly too4 ,so does phosphorus40 8,what is phosphorus80 said ,rollo4 8,why1 it is a substance that burns very easily4 ,it looks like wax1 but it burns very easily1 and with a very bright flame indeed4 ,it takes fire before it is as hot as boiling water40 8,i wish ,i had some phosphorus10 said ,rollo4 8,they keep it at the apothecaries1 sometimes10 said his father4 8,i wish you'd buy a little1 father10 said ,rollo1 8and bring it home1 and let me see it burn4 ,does it cost much80 8,i don't know10 said his father1 8how much it costs4 ,only it is troublesome to keep it4 ,it must be kept under water40 8,why1 sir80 said ,rollo4 8,to keep it from taking fire4 ,even the sun shining upon it would heat it hot enough to set it on fire40 8,o father60 said ,rollo4 8,yes10 said his father2 8and so1 for safety1 they make it in the shape of sticks1 and keep it in a phial filled with water40 8,well1 father10 said ,rollo1 8,i wish you would get a little in a phial1 and let me put a piece of it upon a paper in the sun1 and let me see it catch fire40 8,i'll think of it10 said his father1 8next time ,i go into town4 ,but phosphorus1 you see1 is certainly very inflammable1 because it takes fire very easily1 and burns brightly too4 ,but ,i don't know which would be said to be most inflammable1 sulphur or resin2 for instance1 sulphur inflames the quickest1 but resin will make altogether the greatest blaze40 8,i should think the resin10 said ,rollo4 8,we can't tell by reasoning about it10 said his father2 8it depends on the usage of the word4 ,we will go into the other room1 and look in the dictionary40 ,so saying1 they all went into the parlor again1 and looked into the dictionary1 to learn the precise meaning of the word1 inflammable4 ,the definition given was1 8easily kindled into a flame40 8,then10 said ,mr4 ,holiday1 8if this definition is correct1 the sulphur and the alcohol are most inflammable1 because they are most easily kindled40 ,just then the clock struck1 and ,rollo's mother said1-- 8,why1 ,rollo1 it is half an hour past your bedtime40 ,so ,rollo bade his father and mother good night1 and went out into the kitchen once more to get his safety-lamp1 to go to bed4 ,he stopped1 however1 a moment1 as he was going out of the door1 to say1-- 8,now1 father1 be sure and not forget to buy me some phosphorus40 ,,questions4 ,what did ,jonas say when ,rollo told him about burning the iron filings8 ,how did he make the filings8 ,did the experiment of burning them succeed8 ,why will not a large piece of iron burn in the flame of a lamp8 ,what did ,mr4 ,holiday say to ,rollo's proposal to hold the end of a knitting-needle in the lamp8 ,why will not the terms that are employed in common conversation answer for philosophical use8 ,what is the meaning of ambiguous8 ,what are the different meanings of the word burn8 ,what is the difference between the words freeze and congeal in respect to the extent of their meaning8 ,what question did ,rollo's mother ask in respect to the meaning of the word inflammable8 ,what did ,mr4 ,holiday say8 ,what experiment did he perform to illustrate the two meanings8 ,how was the question at last decided8 ,,chapter ,,iv4 ,,fire ,,in ,,the ,,pasture4 ,a few days after ,rollo's father gave him the instructions on the subject of combustion which are contained in the last chapter1 ,rollo saw ,jonas going across the yard about the middle of the afternoon1 with a lantern in his hand4 ,of course ,rollo called out to him with the usual question in such cases1-- 8,where are you going1 ,jonas80 8,i'm going out into the pasture to set some heaps on fire40 8,well10 said ,rollo1 8and ,i'll go too40 ,rollo ran into the parlor to ask his mother if he might go too4 ,he happened to meet his father just coming in at the front door4 ,he accordingly asked him instead4 8,yes10 said his father1 8but ,i'm rather afraid to have the heaps set on fire this afternoon4 ,i am afraid that the fire will run40 8,run80 repeated ,rollo4 8,yes10 replied his father4 8,tell ,jonas he must be very careful not to let the fire get away from him40 ,rollo ran off in pursuit of ,jonas4 ,when he got to the back yard again1 he saw ,jonas going down the lane almost out of sight4 8,jonas60 said ,rollo1 calling out as loud as he could1 8,jo--nas60 ,so saying1 he ran off after him4 ,he clambered over the great gate which led into the lane1 because he thought that he could climb over it quicker than open it4 ,as soon as he reached the ground on the other side1 he ran on1 calling out1-- 8,jonas6 ,jonas60 ,but ,jonas did not seem to hear him4 ,at any rate he did not stop4 ,on the contrary1 ,rollo was himself stopped1 by hearing a voice behind him1 as if near the house1 calling1-- 8,rollo6 ,rollo60 ,rollo turned to see who it was4 ,it was his cousin ,james1 who was running towards him with all speed4 ,rollo waited for him to come up4 ,james tried to open the gate1 but could not4 8,climb over10 said ,rollo4 ,so ,james climbed over1 and soon reached the place where ,rollo was standing1 and the two boys walked on together4 ,james said that he had come to play with ,rollo that afternoon4 ,rollo said that he was very glad1 and he told ,james that he and ,jonas were going to make some fires in the pasture4 ,the heaps which ,jonas was going to set on fire1 were heaps of decayed wood1 consisting of old stumps1 logs1 and roots1 and other rubbish which he had gathered up from the ground and piled up in the pasture some weeks before4 ,by being left in heaps1 so that the sun and air had free access to them1 they had become thoroughly dry1 and were all ready to burn with a touch4 ,there were not a great many of the heaps1 for it was only a small part of the pasture which had such logs and stumps left in it4 ,the place was on the side of a deep dell1 with a brook flowing through the middle of it at the bottom4 ,rollo and ,james crossed the brook upon a log1 and then ascended the steep side of the hill1 among the heaps which ,jonas was burning4 ,jonas had set two heaps on fire and was just putting a burning brand into the third heap4 ,rollo and ,james wanted ,jonas to let them set the heaps on fire4 ,he told them that they might2 and the boys accordingly went to work1 taking brands from the heaps which were already burning1 and carrying them to the others4 ,the heaps were not only very dry1 but quite hot1 on account of the influence of the rays of the sun beating upon them2 and1 besides this1 there was a fresh breeze blowing1 which made the fires burn up very fiercely4 ,the fires which had been first made soon became so hot1 that the boys could not get near them to take any brands from them4 ,thus they went along from heap to heap1 setting them on fire1 only ,jonas succeeded in setting them on fire much faster than ,james and ,rollo4 ,jonas looked around at them at one time1 and he found them endeavoring to kindle a fire at a large heap which had been built up around a tall stump4 ,the stump was twice as high as ,rollo's head4 ,rollo and ,james were kneeling down upon the ground1 and blowing the end of the brand1 by which they were trying to kindle the fire4 ,but they did not succeed4 ,instead of that1 the wind blew the smoke into their faces4 8,make the fire on the windward side10 said ,jonas4 8,which is the windward side80 said ,james4 8,the side that the wind blows against10 replied ,jonas4 8,yes10 said ,rollo1 speaking to ,james1 8we have got our fire on the wrong side4 ,let us move it round to the other side1 and the wind will blow it for us40 ,so they took up their brands1 and put them upon the other side of the heap4 ,the wind fanned them a little1 but did not make them blaze4 8,just put some dry pieces on10 said ,jonas1 8and leave them4 ,as soon as they get heated a little1 they'll blaze40 ,the boys followed ,jonas's direction1 and1 after putting a few dry pieces upon the smoking brands1 they left this heap1 and went to another2 though they had first to go back to one which was on fire1 and get some more brands4 8,how do you set them on fire so fast1 ,jonas80 said ,rollo4 8,why1 ,i don't stop to watch them10 said ,jonas1 8to see them burn4 ,i put a brand down upon the windy side of the heap1 and then cover it with dry pieces1 and leave it1 and let it burn up in its own time4 ,it will burn as soon as it has time to get heated40 8,yes1 ,james10 said ,rollo2 8my father explained it to me4 ,when wood gets heated above a certain point of heat1 it takes fire4 ,sulphur takes fire before it gets heated so hot40 8,o ,jonas10 said ,rollo1 8why didn't you pile up this heap80 ,rollo had come to a place where there was a long log lying upon the ground1 broken to pieces and decayed1 and near it several fragments of roots and stumps scattered around4 8,o1 come away1 come away from there1 ,rollo10 said ,jonas2 8there is a wasp's nest there40 ,rollo and ,james ran off back towards ,jonas4 8,a wasp's nest80 said ,james4 8,yes10 said ,jonas4 8,i began to pile up that wood1 and heard a buzzing under the log2 and ,i looked down1 and saw some wasps buzzing about a hole4 ,we must burn up the wasp's nest40 8,well10 said ,rollo1 8come and do it now40 ,jonas was coming to burn up the wasp's nest2 but1 as he was passing along towards it1 his attention was suddenly arrested at seeing that the flames from one of the fires were beginning to spread rapidly upon the ground4 ,there was quite a large circle in the grass1 which had been burned over and blackened1 and1 at the outer edges of it1 the flames were still spreading rapidly1--driven by the wind4 8,look6 look60 said ,jonas2 8our fire is running40 8,yes10 said ,james2 8it is burning up all the grass40 ,jonas ran to the edge of the circle1 and began trampling upon the flames1 to put them out4 ,the flames were very light1 for the grass was thin1 and so the fire was easily extinguished at any one spot2 but1 while ,jonas was putting it out in one place1 it was spreading in another1 and he could not put it out so perfectly but that it would flame up and begin to spread again when he went to another place4 ,james and ,rollo stood by somewhat frightened1 and not knowing what to do4 ,illustration3 8,,no10 ,,said ,,jonas2 8,,we ,,must ,,whip ,,it ,,out40--,page #fc4 8,we must get some water10 said ,rollo1 8from the brook4 ,i'll go and get a pail40 8,no1 a watering-pot10 said ,james1 8a watering-pot will be best4 ,let's go and get a watering-pot40 8,no10 said ,jonas2 8we must whip it out with bushes4 ,i'll cut some bushes4 ,come down here with me40 ,so ,jonas ran down to the bank of the brook1 where there were a number of low fir-trees growing4 ,now1 the leaves of the fir-tree are very small and slender1 but they stand very thick upon the branches1 so that they make a very thick and heavy foliage4 ,jonas cut off a branch of the fir-tree1 and gave it to ,rollo4 ,then he cut off another for ,james1 and another larger for himself2 and1 armed with these1 the boys hastened back to the fire4 ,they began to whip and brush the little line of flame1 and they found that they could put it out very easily4 ,every blow which ,jonas struck1 extinguished a line of the fire as long as his branch4 ,rollo and ,james threshed the ground with great vigor1 too1 and they put out a great deal of the fire4 ,in fact1 they soon extinguished all the flames which were creeping up the side of the hill from this first fire1 except at one end1 where it had got into some thistles1 which ,jonas had mowed down some time before1 and which were now lying upon the ground dry and warm1 and so thick that they made quite a hot fire4 ,rollo was whipping upon these thistles1 when ,jonas said1-- 8,stop1 ,rollo2 it is of no use to whip such a hot fire as that2 it is only wasting your strength40 8,then we can't stop it10 said ,rollo4 8,yes10 said ,jonas2 8wait until it has gone over the thistles1 and burned them up1 and then it will come to the thin grass beyond1 and there we can whip it out40 ,so the boys stopped to rest while the thistles were burning1 surveying1 in the meantime1 the large space which had been burned over1 and which looked scorched and blackened4 8,now1 all that grass is spoiled10 said ,rollo4 8,o1 no10 said ,jonas2 8it hasn't hurt the grass4 ,it has only burned the dry tops and the weeds4 ,the roots of the grass are all safe1 and the ashes left by the fire will make them grow all the better next summer40 8,then1 ,jonas1 let's burn the ground all over40 8,no10 said ,jonas2 8if so large a surface gets on fire1 we can't stop it1 till it runs into the fence1 and sets that on fire1--or else gets over into the other field40 ,so saying1 ,jonas pointed to a large level field or pasture over the fence1 where the grass and weeds were much higher than where they were4 ,the grass and weeds in this other field extended back some distance to a piece of woods2 and ,jonas said that1 if the fire got into the woods1 he could not tell how far it would go1 or what mischief it would do4 8,so you see we must be sure and not let the fire get away from us10 said he4 ,just then1 ,jonas saw that the fire was beginning to spread from another of the heaps2 and he went to it to watch it4 ,he said he was going to let it run a little way before he put it out1 for he knew that if a piece of the ground around the heap was once burned over1 the fire would not spread again from the heap4 ,so he waited1 and1 when the circle from that heap had become as large as he wished1 he and the boys whipped it out2 and then they went back to the first fire1 which was now getting beyond the thistles1 so that they whipped that out too4 ,rollo and ,james felt much relieved1 now that they perceived that1 by the aid of their fir-branches1 they had the fires so entirely under their control4 ,about this time1 ,rollo saw his father coming through the trees1 on the other side of the brook4 ,his father had been a little afraid that ,jonas would get into difficulty with his fires1 and had come out to see4 ,he found1 however1 that ,jonas knew how to manage the business4 ,he took a branch1 and began to help the three boys whip the fires1 as fast as they spread beyond the limits which they concluded to allow them4 8,i didn't know that the grass would burn so before10 said ,rollo4 8,it will not10 said his father1 8unless it is both hot and windy4 ,this is an illustration of what ,i explained to you the other day4 ,when grass is heated above a certain point it takes fire4 ,now1 when one blade of grass is burning1 it does not usually produce heat enough to raise the next one to such a degree of heat that it will take fire2 but this afternoon it will2 for now the heat of one little tuft burning is enough to heat the next one sufficiently to cause it to take fire1 because it is already partly heated by the sun40 8,and the wind helps10 said ,rollo4 8,yes10 replied his father1 8the wind helps in two ways4 ,it blows up the grass that is burning1 and makes a greater fire of it1 and then it blows the hot air and flame against the grass next to it4 ,thus it makes the heat greater1 and at the same time drives it against the fresh grass4 ,i presume this fire would not spread at all if there was no wind4 ,you see1 in fact1 that it does not spread much in any direction1 except where the wind blows it40 8,and if there was a wind1 and yet the grass was not hot1 would it spread then80 8,no10 said his father1 8,i presume not4 ,for instance1 in the evening1 when the ground and grass are cool1 ,i don't think the fire would run on the ground4 ,that is1 ,i don't think the heat of one row of blades would heat the next row enough to make them take fire1 unless they were partly heated by the sun beforehand40 8,i should like to try it some windy evening10 said ,rollo4 8,there would be the dew in the evening also1 which would tend to prevent the fire's running40 ,by this time1 all the heaps had been set on fire1 and the circle of fire which spread out from each one had been whipped out2 so that there was now not much danger that the fire would spread1 and ,mr4 ,holiday went away4 ,jonas1 however1 said that he must stay and watch the heaps1 and ,rollo and ,james concluded to stay with him4 ,but1 after a short time1 they became tired of poking the embers2 and so ,rollo proposed to ,james to go with him1 and help him make some charcoal4 8,i have learned how they make charcoal10 said ,rollo4 8,well10 said ,james1 8,i'll go2 but what good will charcoal do us80 8,why1 we can make gunpowder out of it10 said ,rollo4 8,well10 said ,james1 8,i should like to make some gunpowder very much40 ,so the boys went away towards the house1 to get the wood to make their charcoal4 ,,questions4 ,what objection did ,mr4 ,holiday make at first1 to having the heaps set on fire8 ,how was ,rollo arrested when he was in pursuit of ,jonas8 ,what were the heaps composed of which ,jonas was going to set on fire8 ,in what condition were they in respect to inflammability8 ,was there anything besides their dryness which made them particularly inflammable at this time8 ,describe ,rollo's attempt to set a heap on fire4 ,what course did ,jonas pursue8 ,describe the appearances exhibited when the fire began to run4 ,how did ,rollo's father explain to the boys the causes which made the fire run in the grass that afternoon more than at any other time8 ,describe the mode which ,jonas adopted to stop the progress of the fire in the grass4 ,did he always stop it as soon as it first began to run8 ,why not8 ,,chapter ,v4 ,,theory ,,and ,,practice4 ,there is a great difference between understanding theoretically how a thing is done1 and being able actually to do it2 for1 in practice1 various difficulties are apt to occur1 which are not foreseen by one who knows only the theory4 ,rollo and ,james found this to be the case1 in their efforts to make charcoal4 ,rollo felt very confident that he understood the whole process perfectly1 and that he should find no difficulty whatever in carrying it through successfully4 ,he was not aware how many difficulties occur in the practical execution of what appears beforehand to be attended with no difficulty at all4 8,are you sure you can make charcoal80 said ,james4 8,yes10 said ,rollo1 8,i know ,i can4 ,jonas told me everything which ,i must do4 ,first1 we must get some short sticks of wood40 ,he and ,james went to the shed1 and selected some pieces of wood1 which ,rollo said would be suitable for their charcoal bed4 ,he put them into a small saw-horse1 which ,jonas had made for him to saw wood in1 and without much difficulty he sawed a sufficient quantity4 ,james put the sticks into ,rollo's little wheelbarrow as fast as they were sawed4 ,it was not very long before the wheelbarrow was filled nearly full4 8,come1 ,rollo10 said ,james2 8here is enough40 8,no10 said ,rollo2 8let us fill the wheelbarrow full40 8,why1 ,rollo10 said ,james1 8you've got enough already to make a barrel of gunpowder40 8,o1 it won't all come into gunpowder10 said ,rollo2 8some of the wood will burn up1 ,i expect4 ,you see we are going to have slow combustion40 8,slow what80 said ,james4 8,slow combustion10 replied ,rollo2 8don't you know what combustion means80 8,no10 said ,james4 8,it means burning2 that is1 one kind of burning4 ,you see there are a great many kinds of burning4 ,combustion is when it burns all up4 ,if you put your finger in the fire and burn it1 it doesn't burn up1 does it80 8,i suppose it would1 if ,i held it in long enough10 said ,james4 8,yes10 said ,rollo--8but1----there1 ,i think we've got enough now4 ,if you'll be wheeling it along1 ,i'll go and get some fire40 ,so ,james wheeled the wheelbarrow along towards the gate1 and ,rollo went into the house after some fire4 ,he found that the lantern was not there1 for ,jonas had carried it into the pasture2 and as ,dorothy said that it would not be safe for him to carry any coals out1 on such a windy day1 he took some matches of the kind that take fire by being rubbed against any thing hard1 and went along after ,james4 ,rollo had intended to ask ,jonas to cut him some turf1 to cover his charcoal bed with2 but he had not done it yet1 and so he got a spade to carry along with him1 thinking that he and ,james could cut the turf themselves4 ,the spade was rather heavy to carry1 and so he took hold of the handle1 and dragged it along1 letting the blade trail upon the ground4 ,he overtook ,james at the great gate4 ,they passed through the gate1 and went on1 ,james trundling the wheelbarrow1 and ,rollo following him with the spade4 ,at last1 they came to the place where ,rollo had determined to have his charcoal bed4 ,it was a smooth piece of grass ground1 a short distance beyond the garden1 and so far from any fence that there was no danger of setting the fences on fire4 ,it was1 in fact1 a very suitable place4 ,rollo had selected it with great discretion4 8,and now10 said ,rollo1 8the first thing is to dig up some turf4 ,we want some large pieces of turf40 8,what for80 said ,james4 8,why1 to cover up our charcoal with40 8,what do you want to cover it up for80 said ,james4 8,besides1 ,i should think you would want to make it1 before you cover it up40 8,why1 that is the way we make it10 said ,rollo2 8we have to cover the wood up with turf40 8,o1 the wood10 said ,james1 8you said the charcoal40 8,no1 the wood10 replied ,rollo2 8we want to cover up the wood40 8,then it won't burn10 said ,james1 8if you cover it all up with turf40 8,yes10 replied ,rollo2 8it will burn very slowly4 ,we don't want it to burn fast4 ,that is the very reason why we cover it up with turf1 to keep it from burning fast40 8,i should think it would be best to pour a little water on it10 said ,james1 8if it was burning too fast40 8,no10 said ,rollo2 8we must cover it up with turf4 ,jonas said so4 ,and ,i must cut it40 ,so ,rollo began to cut turf with his spade4 ,he found it1 however1 very hard4 ,it is very hard work to cut turf4 ,after he had cut a square place out1 it was very difficult to crowd the spade under it1 so as to get the piece of turf out4 ,he1 however1 succeeded in cutting one piece2 and then the next was easier4 ,after working patiently for about a quarter of an hour1 stopping occasionally to rest1 and to wish that ,jonas would come and finish cutting the turf for him1 he succeeded in laying bare a spot of ground large enough for his coal bed2 and1 on looking at the pieces of turf which he had got off1 he could not but hope that they might possibly be enough to cover his wood with4 ,at any rate1 he thought he would try it2 for he could cut more1 he said1 if at last he found that he should want more4 ,he therefore began to pile up his wood in the spot left bare by the removal of the turf4 8,we must leave a hole down in the middle10 said he to ,james1 8to put the fire in4 ,i ought to have had some boards for it40 ,rollo wanted ,james to go up to the house1 and get some short boards2 but ,james said that he did not know where he could find any1 and finally ,rollo concluded to make the hole as well as he could by leaving a space1 in piling the wood4 ,he succeeded pretty well in doing this4 ,in fact1 he piled his heap very well1 making it compact and snug1 and rounding it up on the top as ,jonas had directed1 so that it could be easily covered with the turf4 8,now10 said ,rollo1 8we will cover it up4 ,you hand me the pieces of turf1 ,james1 and ,i will put them on40 ,james handed ,rollo one large piece of turf1 and ,rollo placed it against the side of his heap of wood4 ,he then brought him a second1 and ,rollo attempted to place it next to the first1 but it did not fit very well4 8,there now10 said ,rollo1 8,i haven't got any knife40 8,what do you want a knife for80 asked ,james4 8,to cut off some of this turf1 and make it fit into its place40 8,must you make it fit exactly80 asked ,james4 8,yes10 said ,rollo2 8so ,jonas said4 ,but ,i can cut it with the spade40 ,so ,rollo laid down the piece of turf upon the ground1 and attempted to cut away one side of it with the spade4 ,he could not do it very well4 ,he was not strong enough to do it with one blow1 and1 in striking down the spade upon it repeatedly1 he could not always hit the same place2 and so he mangled the edge1 and bruised it to pieces4 ,however1 it fitted better than it did before1 though there was still an interstice left1 at the lower corner1 between the two pieces of turf and the ground4 8,it doesn't fit exactly10 said ,rollo2 8but no matter4 ,there must some air get in40 ,he placed the other pieces of turf in a row around the heap4 ,after he had gone all around1 there were some left1 but not enough to cover the top over4 ,they1 however1 covered it as well as they could1 and then ,rollo said he would kindle the fire and put it in2 and then1 while it was getting a burning1 he would cut some more turf1 and finish covering it4 ,they had some difficulty in getting fire4 ,in the first place1 the match would not light4 ,rollo did not see any thing to rub it upon but the handle of the spade1 and that was so smooth and glossy1 from long use1 that it did not produce friction enough to inflame the match4 ,finally1 ,james rubbed one of the matches upon the side of the wheelbarrow1 and that lighted it2 but then they had no kindling ready1 and1 of course1 as the large sticks of wood could not be lighted by a match1 ,james1 after holding it until it was just ready to burn his fingers1 threw it down4 ,then ,rollo did what he ought to have done before4 ,he collected together some leaves and dried grass1 and splinters of wood1 which he found lying about1 so as to have some combustibles ready when the next match should be lighted4 ,by this means they soon had a little fire at a short distance from the heap of wood which they had prepared for their charcoal bed4 ,as soon as their fire began to burn1 they attempted to move it into the hole in the middle of the heap of wood4 ,they took off the little sticks and chips from the fire1 which were blazing at one end1 and dropped them one by one into the hole4 8,i don't believe the fire will burn down in that hole10 said ,james4 8,yes it will10 replied ,rollo4 8,that's the way they always set the charcoal beds on fire40 ,but1 notwithstanding ,rollo's confidence1 the chips and sticks1 though they had burned very freely while in the open air above1 did not appear at all inclined to burn in the hole4 ,one reason was1 that the boys did not wait long enough for them to get well heated4 ,the ends which were together were on fire1 it is true2 but the other ends were cold1 and the heap of wood was cold1 so that every little brand1 though it was blazing when the boys took it off the fire1 was at once chilled below the point at which combustion continues as soon as it was dropped into the hole4 ,consequently1 after they had dropped all the pieces in1 they saw nothing but smoke come out1 and even the smoke grew dim4 8,it is all going out10 said ,james4 8,we must make a bigger fire10 said ,rollo4 8,i wish ,i had a pair of tongs here to take out the old sticks1 and then we would make a bigger fire40 ,but ,rollo had no tongs2 and so he was obliged to take down his pile in part1 in order to get the dead brands out of the middle of it4 ,then they built another little fire4 ,they waited for this until it was much hotter2 and so they succeeded at last in getting a little fire to burn in the middle of their heap of wood4 8,as soon as it begins to burn pretty well10 said ,rollo1 8,i must cover it all up with sods40 8,then that will put it all out10 said ,james1 8,i know40 8,no10 said ,rollo2 8it will only make it burn slow40 8,i think it will put it all out10 replied ,james4 ,rollo himself had some misgivings whether his wood would really burn very well1 when all covered up with turf1 and he thought that at any rate he would let it get well on fire before he put the turf on4 ,in the mean time1 he took the spade1 and began to cut the turf1 to have it ready4 ,he found it now very hard to cut the turf1--both because he was tired of cutting it1 and also because he had now to begin in a new place1 as his woodpile covered the place which he had taken the turf off from before4 ,it is always harder to cut the first turf than it is those that come afterwards4 ,rollo succeeded in getting one or two more pieces1 and as soon as the heap of wood seemed to be pretty well on fire1 he put these pieces on over the top2 but they were not enough to cover it1 and as the fire increased1 the flames came up more and more from the spaces left uncovered4 8,o dear me60 said ,rollo4 8,i can't cut the turf fast enough to cover it40 8,shovel up some earth1 and put on10 said ,james4 ,illustration3 ,,so ,,rollo ,,began ,,to ,,shovel ,,up ,,the ,,earth4--,page #ha4 ,so ,rollo began to shovel up the earth from the place which he had made bare by taking off the turf1 and to throw it upon the fire4 ,this had an immediate effect in suppressing the flames which were breaking out2 and by continuing to throw on earth1 he at length got the fire fairly subdued4 ,the earth did not cover the heap4 ,it slid down among the interstices of the wood1 and smothered the fire1 so that pretty soon ,rollo thought that the fire was burning slowly enough to make charcoal4 8,if we had some water in a watering-pot1 that would be better10 said ,james4 8,so it would10 said ,rollo4 8,then we could make the fire burn just as slowly as we pleased10 said ,james4 8,yes10 said ,rollo2 8let us go and get a watering-pot4 ,we can get back before it burns up again40 8,well10 said ,james2 8and we'll carry up the wheelbarrow and the spade40 ,so ,rollo took the wheelbarrow1 and ,james the spade1 and they walked along towards the house1 talking about what they should do with their gunpowder when they had got it made4 ,they came at length to a narrow place in the walk1 where ,james walked on before1 ,rollo following him with the wheelbarrow4 ,rollo trundled the wheelbarrow along very close to ,james's heels1 and so ,james1 to avoid it1 ran on4 ,rollo followed1 pursuing him1 and so ,james1 to escape1 ran off upon the grass1 to get out of ,rollo's way4 ,but ,rollo still followed him1 both boys making the air resound with shouts of laughter1 until1 at length1 ,james1 finding that he was still pursued1 turned around1 and planted the blade of the spade upon the ground1 just before the wheel of the wheelbarrow4 ,the wheel ran up against it1 and was stopped1 and thus ,james was protected4 ,the boys amused themselves in this way for some time1 entirely forgetting about their watering-pot4 ,after satisfying themselves1 however1 with this fun1 they began to move along towards the house4 ,they found ,rollo's little watering-pot1 and they carried it to the pump to fill it with water4 ,they got into a great frolic at the pump1 too4 ,james would hold the watering-pot1 while ,rollo pumped1 and then1 when it was full he made believe try to sprinkle ,rollo1 to pay him1 as he said1 for running over him with his wheelbarrow4 ,rollo would run off around the yard1 and ,james after him1 holding up the watering-pot1 with the spout elevated1 ready to discharge a shower of water upon him1 if he could only get near4 ,when he got pretty near1 he would tip up the watering-pot1 and out would pour the water in a great number of curving jets1 which spouted out towards ,rollo1 as he ran4 ,when the water from the watering-pot was exhausted by this operation1 they would go back to the pump1 and fill it again4 ,in the mean time1 the wood of their charcoal bed was all burning away4 ,it was an hour1 in fact1 before they got back to the charcoal bed2 and when they reached it1 it was a mere bed of embers and ashes4 ,the combustion1 instead of having been slow1 had gone on with great violence and rapidity1 and the wood was entirely consumed4 ,rollo and ,james looked upon it for a few minutes in silence4 8,we'll put it out now1 at any rate10 said ,rollo2 and he took the watering-pot out of ,james's hand1 and began to pour the water upon the burning bed before him4 ,it made a great hissing and steaming2 and1 when he had done1 the boys had before them plenty of hot mud1 made of ashes and water1 but no charcoal4 ,,questions4 ,what preparations did ,james and ,rollo make for their charcoal bed8 ,did they find it difficult or easy to cut the turf8 ,how did they arrange the wood8 ,did ,rollo begin right to cover the wood with turf8 ,what was the first difficulty which he encountered8 ,what tool would have been best for cutting the turf into the right form8 ,what tool did ,rollo attempt to use instead8 ,what was the difficulty in the operation of it8 ,what plan was at length proposed for checking the combustion1 instead of putting on a tight covering of turf8 ,why did they leave their work and go to the house8 ,what detained them on this expedition8 ,in what condition did they find the charcoal bed on their return8 ,,chapter ,,vi4 ,,gunpowder4 ,when ,rollo and ,james went home it was nearly tea-time1 and they found ,jonas just coming from the pasture4 ,they told him of the ill success of their experiment in charcoal-making1 with countenances expressive of great disappointment and chagrin4 8,it is no matter10 said ,jonas2 8you have had your afternoon's amusement1 and that's all you want1 isn't it80 8,no1 indeed10 said ,rollo2 8by no means40 8,why1 what else do you want80 asked ,jonas4 8,why1 we want some gunpowder10 said ,james4 8,we are going to make our charcoal into gunpowder40 8,you needn't have made a charcoal bed for that10 said ,jonas4 8,you can get all the charcoal you want to make gunpowder with1 out of the kitchen fire40 8,the kitchen fire60 said ,rollo4 8,yes10 replied ,jonas4 8,you can pick up plenty of little black coals in the corners40 8,will they do80 asked ,james4 8,yes10 said ,jonas2 8why not80 8,i didn't know that they were charcoal10 rejoined ,james4 8,yes10 said ,jonas4 8,and will you help us make our gunpowder80 asked ,rollo4 8,why1 it is rather a dangerous business10 said ,jonas4 8,why1 we will be very careful1 you know1 ,jonas1 not to get blown up10 said ,rollo4 8,o1 ,i'm not afraid of getting blown up with any gunpowder you can make4 ,that wasn't the kind of danger ,i was thinking of40 8,what danger then80 said ,rollo4 8,why1 danger of getting the sulphur on your clothes1 and smutting your face with the charcoal40 8,why1 ,jonas10 replied ,rollo1 8if we get the sulphur on our clothes1 we will brush it off again2 and1 as to the smutting1 we won't touch the charcoal to our faces40 8,it is very difficult10 replied ,jonas1 8to have any thing to do with charcoal1 without getting blacked with it4 ,you can hardly look at it without crocking your face40 8,o ,jonas10 said ,james1 8,i could1 ,i know40 8,then1 besides10 continued ,jonas1 8you can't brush the sulphur off your clothes4 ,if you once get it on1 some of it will stay1 and your clothes will always smell of sulphur whenever you come near a fire4 ,i don't think that your mother would be willing that you should have any thing to do with sulphur and charcoal40 8,i mean to ask her10 said ,rollo4 ,rollo went in to ask his mother1 but he found that tea was ready1 and so he and ,james went in and took their places at the tea-table4 ,when the boys proposed their plan of making gunpowder1 they found ,rollo's mother1 as ,jonas had supposed1 quite averse to any such operations4 ,however1 when his father came in and heard their conversation on the subject1 he said that he would take charge of the business1 and then his mother would have no objection4 8,well1 sir10 said ,rollo1 8,i'm glad of that2 for perhaps ,jonas wouldn't know how to make it40 8,he can prepare the materials1 at any rate10 said his father4 8,so1 after tea1 you may go out and ask him to get three tea-cups1 and to put about three or four tablespoonfuls of sulphur in one1 and of saltpetre in another1 and charcoal in another4 ,only the saltpetre and the charcoal must be pulverized40 8,pulverized80 said ,rollo2 8what do you mean by that80 8,why1 powdered1--that is1 pounded up very fine40 8,how shall he pound them80 said ,rollo4 8,in the iron mortar10 said his mother4 8,dorothy will give it to him40 8,and when they are all ready10 continued ,rollo's father1 8come and tell me40 ,accordingly1 immediately after tea1 ,rollo and ,james went out to give ,jonas the directions about preparing the materials4 ,dorothy gave ,jonas the mortar4 ,she also brought out three tea-cups1 and put them upon the kitchen table4 ,jonas picked up from the corner of the fireplace a few small coals1 and put them into the mortar and then1 took up the pestle4 8,o1 more10 said ,rollo2 8we want more than that40 8,yes10 said ,jonas2 8but we must take a little at a time40 8,why80 asked ,rollo4 8,because10 replied ,jonas1 8if ,i put much into the mortar at once1 ,i can't make it fine4 ,i must only have a little1 and then the pestle and the bottom of the mortar come close together1 and so it grinds up the smallest pieces40 ,when ,jonas had pounded up the charcoal which he had put in at first1 he poured the black powder out into one of the tea-cups1 and then put in more charcoal1 which he powdered as before4 ,he proceeded in this way until he had filled one of the tea-cups nearly half full4 ,he then washed out the mortar1 and put it down to the fire to dry4 ,then he took a glass jar1 which ,dorothy had brought him from the closet1 and which was nearly full of a substance which looked like salt1 and poured some of it into the mortar4 8,is that the saltpetre80 said ,rollo4 8,yes10 replied ,jonas4 8,it looks like salt10 said ,rollo4 8,yes10 rejoined ,jonas1 8and tastes a little like salt40 ,rollo and ,james both wanted to taste a little of the saltpetre1 and they did4 ,in the mean time1 ,jonas had poured some of it into the mortar1 and was grinding it up with his pestle2 and1 when ,rollo asked him where saltpetre came from1 and what it was for1 ,jonas said he did not know any thing at all about it1 and went on pounding and grinding with his pestle4 ,dorothy now brought out another jar1 containing sulphur2 and as soon as ,jonas had finished pulverizing his saltpetre1 and had put it all into its cup1 he poured out some of the sulphur into the third cup4 ,the jars and the mortar were now put away1 and ,jonas got two sheets of wrapping-paper1 and put upon the table1 for he said he thought it probable that they might want some1 in trying the powder4 8,i expect your father will want a pair of scales1 too10 said ,jonas4 8,what for80 asked ,rollo4 8,to weigh out the materials10 replied ,jonas4 8,i don't know what the proportions are2 but ,i suppose that they must be mixed in right proportions40 8,what are the right proportions80 asked ,rollo4 8,i don't know10 said ,jonas1 8but ,i suppose your father will know40 8,well10 said ,rollo1 8,i'll go and call him40 ,so ,rollo went in1 and told his father that they were all ready4 ,he found his father at the library looking at a large book4 8,come1 father10 said ,rollo4 8,seventy-five parts of saltpetre10 said his father1 reading out of his great book1 and appearing not to pay any attention to what ,rollo said1--8seventy-five parts of saltpetre1 eleven and a half of sulphur1 and thirteen and a half of charcoal4 ,seventy-five to eleven1 that is1 about seven to one4 ,say1 six times as much saltpetre as of each of the other two4 ,that will be near enough40 8,come1 father10 said ,rollo again2 8we're all ready40 8,yes10 said his father1 8,i'll come40 ,rollo returned into the kitchen1 and his father followed him4 ,his mother came1 too1 for she wanted to see them make the gunpowder4 ,jonas asked ,mr4 ,holiday if he should want a pair of scales4 8,no10 said he1 8we can guess at the proportions near enough4 ,we can't expect to make very good gunpowder40 8,why not1 sir80 said ,rollo2 8the things are all good that we are going to make it of40 8,very likely10 said his father2 8but we cannot make them fine enough1--nor mix them intimately40 8,why1 father10 said ,rollo1 8,jonas has made them very fine indeed40 8,yes1 ,i have no doubt that he has pulverized them as well as it can be done in a mortar4 ,but it is not possible to make them as fine in that way as they do in the powder-mills4 ,then1 to mix them properly1 they ought to be wet and ground together a long time4 ,we can't stop to do that4 8,and now1 first10 he continued1 8,i want you all to observe how these various materials will burn by themselves1 and then see how differently they will burn together40 ,mr4 ,holiday then took up a coal of fire1 and put it upon the shovel2 and he asked ,jonas to hold it for him in the fireplace1 under the throat of the chimney1 so that the smoke and fumes might not come out into the room4 ,he then took from the cup which had the sulphur in it1 a little of the sulphur upon the point of his knife1 and laid it down gently upon the coal of fire4 ,it burned with a very small and faint blue flame4 ,it burned very slowly1 and the flame continued for some time2 but the flame was not much bigger than the sulphur itself which caused it4 ,he then tried the same experiment with the saltpetre4 ,the effect was very different1 though in this case there was scarcely any flame4 ,it made a little faint flash1 accompanied with a slight crackling sound4 ,then he tried the charcoal1 but it did not appear to burn at all4 ,it lay in a little black heap upon the burning coal1 just as ,mr4 ,holiday put it on4 ,after a time1 however1 it began to grow red upon the under side1 and finally became red throughout2 and then it could hardly be distinguished in appearance from the coal which it was lying upon4 8,so you see10 said ,mr4 ,holiday1 8that these three ingredients are not very combustible by themselves2 at least1 they burn very quietly1 and with very little flame4 ,now1 we will mix them together4 ,we want a tea-spoon ,dorothy40 ,dorothy brought a tea-spoon4 8,and the mortar4 ,i can mix them better in the mortar40 ,so ,dorothy brought the mortar1 too4 ,mr4 ,holiday measured out six tea-spoonfuls of saltpetre from the cup which contained that ingredient1 and put it into the mortar4 8,there must be about six times as much saltpetre as sulphur and charcoal10 said he4 8,that is not exact1 but it will be near enough1 ,i presume4 ,now1 ,i will put in one tea-spoonful of sulphur and one of charcoal4 ,i suppose1 however1 ,i ought to go by the weight1 and not by bulk40 8,what do you mean by that1 sir80 said ,james4 8,why1 it ought to be six times as much saltpetre by weight1 and not by measure4 ,it wouldn't take six tea-spoonfuls of saltpetre to weigh six times as much as one tea-spoonful of sulphur1 ,i presume2 for ,i should think saltpetre is much heavier4 ,i suppose saltpetre is heavier than either sulphur or charcoal4 ,so ,i will put in two tea-spoonfuls of sulphur1 and two of charcoal1 to make up for their lightness40 8,i should think it would be better to weigh them10 said ,rollo4 8,yes1 it would be rather better1 but it would take more time1 and we will see how our gunpowder burns without being exact in the proportions2 and if it does not succeed1 then perhaps ,i will try again1 and weigh out the ingredients1 and see if it makes the gunpowder any better40 ,while saying this1 ,mr4 ,holiday had been gently rubbing and mixing the powders in the mortar4 ,he said he must rub them gently1 for1 as the pestle and mortar were both of iron1 if he rubbed hard1 he might possibly set his gunpowder on fire4 8,o father10 said ,rollo1 8,i don't believe it would take fire by just rubbing in a mortar40 8,no10 said his father1 8,i don't think it would1 myself2 but it might1 possibly4 ,i have heard of powder-mills taking fire by the friction of the mills in grinding the powder1--though ,i don't suppose it would be possible to set fire to any such powder as we can make1 by rubbing it in a mortar4 ,still it is well to be on the safe side40 ,after ,mr4 ,holiday had mixed the compound sufficiently1 he poured it out of the mortar upon the sheet of brown paper which ,jonas had prepared4 8,is that gunpowder80 said ,rollo1 in a tone of incredulity4 8,i think it is somewhat doubtful myself10 replied his father4 8,it does not look like gunpowder10 said ,rollo's mother4 ,this was true4 ,the substance before them was different in its appearance from gunpowder in two respects4 ,it was not grained like gunpowder1 but was fine and impalpable1 like dust4 ,then it was of a lighter color4 ,mixing so much saltpetre1 which was white1 with the charcoal and sulphur1 prevented its being so dark as common gunpowder4 ,at least1 ,mr4 ,holiday thought that this was the reason1 and he suspected that1 in some way or other1 he had got too much of the saltpetre in his composition4 ,at any rate1 the powder looked like nothing but a heap of gray dust4 8,the proof of the pudding is the taste10 said he2 8so we'll try it40 ,he accordingly took up about half a tea-spoonful of the gunpowder1 and put it upon the shovel1 and he asked ,jonas to hold it in the fireplace1 so that1 if it did burn1 the smoke might go up chimney4 ,rollo wanted to touch it1 and his father gave him leave4 ,so he took up a small coal of fire with the tongs1 and touched the top of the little heap4 ,to their great pleasure and surprise1 it blazed up suddenly and violently4 8,yes10 said ,rollo1 8it's gunpowder6 ,it's real gunpowder1 ,i do believe60 8,let me touch some of it10 said ,james4 ,mr4 ,holiday put another half tea-spoonful upon the shovel and let ,james touch it4 ,it flamed up like real gunpowder1 just as before4 8,the great peculiarity of gunpowder10 said ,mr4 ,holiday1 8is1 that it burns without air4 ,other combustibles1 when shut up in a confined space1 will not burn4 ,if they are set on fire previously1 they go out when they are closely shut up from the air4 ,but gunpowder burns the more violently the more closely it is shut up4 ,there seems to be something in some of the ingredients which takes the place of air2 so that1 when people drill a hole in a solid rock1 and pour gunpowder down to the very bottom of it1 in a place where nothing else would burn1 and then ram down pounded bricks into the top of the hole1 so that no air can get in1 if they get fire to the gunpowder1 it will burn there more fiercely than any where1 and tear the rock to pieces40 8,how do they get the fire down80 asked ,rollo4 8,they put a wire in10 replied his father1 8before they put in the bricks2 and then when the bricks are pounded in hard1 they draw up the wire1 and that leaves a little hole extending down to the powder4 ,then they pour fresh powder into the hole1 and put shavings on the top1 and then set the shavings on fire1 and run away40 8,i should like to see them blow up a rock10 said ,rollo4 8,we must make an artificial rock for our gunpowder10 replied his father1 8and see if our powder will burst it4 ,i'll try1 if you will go into the other room1 and get the ball of twine out of the drawer40 ,while ,rollo was gone after the ball of twine1 his father took a piece of strong wrapping-paper1 which ,jonas got for him1 and1 bending it around over his hand in a peculiar manner1 he formed it into a conical sort of cup1 into which he poured the gunpowder which he had made4 ,this paper cup was pointed at the bottom1 growing larger and larger upwards4 ,he then folded over the upper part1 so as to enclose the powder completely2 and1 when ,rollo brought the twine1 he began to wind the twine around it1 as if he was going to tie it up4 ,rollo and ,james expected that he was going pretty soon to cut off the string1 and tie it2 but instead of that1 he went on winding it up like a ball4 ,after he had carried the string round a number of times1 he began to wind it tighter and tighter1 taking care1 however1 always not to pass the twine over the little tip or apex of the cone4 ,by this means1 in a short time the whole paper was covered in every part with the twine except the apex1 which remained exposed4 8,there10 said he1 when he had finished1 8,i have enclosed the powder now in this ball1 and confined it tight4 ,we can imagine this to be a rock4 ,the air cannot get at it4 ,if it burns at all1 it must burn by means of its internal composition4 ,now we will go out and set it on fire4 ,jonas must get a short board and a few shavings40 ,while ,jonas was gone after the board and shavings1 ,mr4 ,holiday made a little more gunpowder in the mortar for priming1 as he said4 ,when it was ready1 they went out to the door1 where they found ,jonas with a board1 and a little basket of shavings4 ,mr4 ,holiday put the board down upon the ground at a little distance from the door4 ,then he placed his wound parcel of gunpowder upon the board1 with the tip down4 ,with his penknife he made a little opening into the gunpowder at the tip1 so that a little of it came out upon the board4 ,he then poured his priming down at the same place1 and laid the shavings carefully upon it4 ,he finally folded up a paper1 and lighted it in the house1 and came up cautiously and lighted the shavings4 ,the others all stood upon the piazza looking on1 and ,mr4 ,holiday himself1 as soon as he saw the shavings began to burn1 retreated to the same place of security4 ,the shavings burned slowly for some time4 ,the flame approached nearer and nearer to the charge2 for a minute1 the flame seemed to come from the very apex of the cone1 and ,rollo had just come to the conclusion that the powder would not go off1 when suddenly there was a flash and a great puff of smoke1 and immediately after a loud explosion4 ,the children ran to the spot and found that the ball in which the gunpowder had been enveloped1 was torn all to pieces1 and the fragments of the twine were slowly burning4 ,,questions4 ,why was ,rollo particularly sorry that he failed in making the charcoal8 ,what did ,jonas tell him8 ,what dangers did ,jonas anticipate in his making gunpowder8 ,what did his father say to his request8 ,what preliminary arrangements were made8 ,what is the meaning of pulverize8 ,of impalpable8 ,how did ,jonas pulverize the charcoal8 ,how did ,rollo find his father employed1 when he went to call him8 ,what did his father say that the proportions were8 ,did he attempt to be exact8 ,did he suppose that the parts ought to be measured by bulk or by weight8 ,which did he think was the heaviest of the materials8 ,how did he make allowance for this8 ,what was the success of the experiment8 ,how did their gunpowder differ from real gunpowder in appearance8 ,in what respect does gunpowder differ from other highly combustible substances8 ,how did ,mr4 ,holiday confine his gunpowder1 to show whether it had the property of burning without a supply of air8 ,,chapter ,,vii4 ,,the ,,alarm4 ,after the explosion1 ,james said that it was time for him to go home4 ,it was about sundown4 ,rollo said that he would go home with him to keep him company1 if his mother would let him4 ,she had no objection1 and ,rollo and ,james went away together4 ,rollo went with ,james to the door of the house where ,james lived1 and then1 bidding him good night1 he left him1 and began to return4 ,when he had got about half way home1 he saw a lady and a gentleman coming along the road4 ,as he approached nearer to them1 he found that it was his father and mother1 taking a walk4 ,rollo joined them4 ,they said1 however1 that they had walked far enough1 and so in a few minutes they turned round1 and went towards home4 8,didn't our gunpowder go pretty well1 father80 said ,rollo4 8,yes10 replied his father1 8better than ,i expected it would1 without being more accurate in our proportions40 8,it was a very good experiment1 ,i think10 said ,rollo4 8,yes10 replied his father1 8it was a good experiment1 and it will prove useful to you1 if it impresses upon your mind the nature of that property of gunpowder on which its power depends2 namely1 that its combustion is within itself4 ,it doesn't need the outward air40 8,yes1 sir10 said ,rollo4 8,there are other things that are more inflammable than gunpowder2 that is1 they will take fire more easily1 and make a greater flame2 but they cannot burn unless they have air4 ,there is phosphorus1 for example2 it will take fire a great deal more easily than gunpowder1 and ,i believe it will make a greater flame2 but it must have air1 and it can't burn any faster than fresh air can get to it40 8,then phosphorus will take fire easier than gunpowder10 said ,rollo's mother4 8,yes10 said ,mr4 ,holiday2 8that is1 with a less degree of heat4 ,i presume that1 if ,i were to rub phosphorus in a mortar1 it would almost certainly take fire4 ,these friction matches are made of some composition of phosphorus1 and the heat of rubbing the end upon a board is enough to set the composition on fire4 ,but gunpowder would not burn by being rubbed so4 ,but still1 though less heat is required to inflame phosphorus than gunpowder1 still air is necessary for the phosphorus1 and it is not necessary for gunpowder2 so that gunpowder will burn in confined places when phosphorus will not4 8,suppose1 for instance10 continued ,mr4 ,holiday1 8that we had a barrel of phosphorus and a barrel of gunpowder1 both open at the top1 and were to set them on fire4 ,the gunpowder would burn at once from the top to the bottom at a single flash1 without any help from the outward air4 ,the phosphorus would take fire on the top1 and burn down gradually1 as fast as the air could come to the flame4 ,it would burn very fast and furiously1 and ,i think it likely it would make1 in all1 a greater flame than the gunpowder4 ,but then it would burn gradually and only as fast as it could get a supply of fresh air2 so that if1 while it was burning1 men were to come and cover it all over with wet blankets1 so as to keep away the air1 it would smother it1 and put it all out40 8,the water of the wet blankets would put it out10 said ,rollo4 8,no10 said his father2 8it would be the same with any thing dry1 if it would keep out the air4 ,i presume1 if a great quantity of dry sand was poured over it1 it would put it out4 ,but wet blankets or dry sand put over a barrel of gunpowder1 even if we could have time to do it1 would have no effect at all in stopping the burning2 for the burning is not dependent upon the outward air at all2 the combustion is entirely within itself2 that is the essential peculiarity of gunpowder1 on which all its powers depend40 8,i don't see why it should burst open what it is confined in1 after all10 said ,rollo's mother4 8,nor ,i10 said ,rollo4 8,i should think it might burn up1 without tearing things to pieces40 8,i don't know myself10 replied ,mr4 ,holiday1 8exactly why it has such an expansive force4 ,i'll look in some book1 when ,i get home1 and see if ,i can find an explanation of it4 ,but1 at any rate1 you see the difference in the manner of its burning4 ,now1 there is wood1 for example2 it burns by degrees1 as fast as the fresh air can come to it4 ,when you put a stick of wood upon the fire1 if it is dry and warm1 and the fire is hot1 first the outside takes fire4 ,this burns because the air can get access to it4 ,but the inside does not burn at all4 ,if we were to take a stick off the fire1 after it had been burning for half an hour1 and saw it in two1 we should find the middle as sound and solid as ever40 8,should we sir80 said ,rollo2 8,i should expect to find it all black coals40 8,no10 replied his father4 8,the blackness only extends in a very little distance2 and the wood within is not burned any faster than the outside gets burned off out of the way1 so as to let the air come to the inner layers1 one after another4 8,and there is a very curious contrivance in nature10 continued ,mr4 ,holiday1 8for supplying the fire all the time with fresh air40 8,what is it80 asked ,rollo's mother4 8,why1 air is so constituted1 that heat swells it1 and makes it lighter2 so that the air that is next to the outer layer of the wood1 when the wood first begins to burn1 becomes heated1 and swells1 and so1 growing lighter1 it immediately rises and goes out of the way1 and a new supply of good1 fresh air comes in to take its place4 ,by the time that this is no longer good to promote the burning1 it gets heated and rises2 and so1 there is a constant stream of hot air1 that has passed through the fire1 rising1 and fresh air coming in to take its place4 ,that is the reason1 ,rollo1 why we have chimneys in a house4 ,a chimney is nothing but an opening over a fire1 so that the air can rise up through it as fast as it passes through the fire1 and all the smoke and sparks pass up too40 8,i thought a chimney was only to let the smoke up10 said ,rollo4 8,no10 replied his father1 8that is not all1 by any means4 ,if a fire made no smoke1 it would still be almost as necessary as it is now to have a chimney4 ,in fact1 some fires do not make any smoke2 some kinds of coal1 dug out of the ground1 do not make any smoke1 and charcoal fires do not make any smoke2 but still it is always necessary in such cases to have chimneys4 8,because10 he continued1 8you must understand1 that air gets changed in passing through a fire1 so that it will not answer afterwards either to breathe1 or to make a fire burn again2 and therefore there must be some way for it to escape1 not only out of the way of the fire1 but also out of the room where people want to live and breathe4 ,there is always such a stream of air rising up from every fire1 great or small1 even from a lamp40 8,why1 father1 is a lamp a fire80 said ,rollo4 8,certainly10 said his father1 8it is a small fire made by burning oil on the top of a wick1 and the hot air rises in a constant stream above it4 ,so in a room1 if there was no chimney over the fire1 all the air that had passed through the fire1 and become heated1 would ascend to the top of the room4 ,i saw the proof of this once1 in a very singular manner40 8,how was it1 sir80 said ,rollo4 8,it was one day when ,i was travelling4 ,it was in the winter4 ,i came to a hotel and was going up stairs to my room just before dinner4 ,when ,i got to the head of the stairs1 and was about going along the passage-way to my room1 ,i saw1 a little way before me1 a door open1 which led into another room2 and there was a thick stream of white smoke1 pouring out in the most beautiful manner1 at the upper part of the door1 and falling up to the ceiling40 8,falling up60 said ,rollo4 8,yes10 said his father4 8,it looked precisely like a little waterfall1 falling up4 ,there was no smoke at all coming out1 except close to the top of the door2 and1 as soon as it got out1 it went up to the ceiling of the entry1 and from that it spread all around like water4 ,it was very beautiful1 but ,i had not time to stop to admire it1 for ,i presumed that the room was on fire40 8,and did you cry fire80 said ,rollo4 8,no10 replied his father4 8,it is never best to call out for help1 unless you are sure you need it4 ,my room was very near4 ,i remembered that my pitcher was full of water in my wash-stand4 ,i ran and got the pitcher1 and went into the room which the smoke was coming from4 ,i saw a great blazing by the side of the fireplace40 8,and did you run and pour your water on80 said ,rollo4 8,no10 replied ,mr4 ,holiday2 8,i didn't pour it on1 for in that case a great deal of it would have all run down upon the floor1 and been wasted4 ,i went up to the place1 and put my hand into the pitcher1 and began to sprinkle the water on as fast as ,i could1 and it put the fire right out at once40 8,what was it that was burning80 asked ,rollo4 8,a basket of chips10 replied his father4 8,a basket of chips60 repeated ,rollo4 8,yes10 replied his father4 8,it seems that the man who occupied that room had gone out without taking down his fire1 and he had left a small basket1 with a few chips in the bottom of it1 near the corner4 ,now1 while he was gone1 one of the sticks of wood had burned off1 and the two ends outside of the andirons1 not having been burned at all1 were heavy2 and so the ends of the stick fell over1 one on one side and the other on the other4 ,the stick which fell over towards the basket1 threw a coal against it and set it on fire2 and the basket1 being very dry and thin1 burned very fast4 ,scarcely any thing of the size makes a greater blaze1 than a basket1 for it is thin1 and of such a form that the air can get to it on both sides40 8,that was a narrow escape10 said ,rollo4 8,yes10 replied his father1 8,i think it was40 8,and ,i expect the landlord thanked you for saving his house from burning up10 said ,rollo4 8,on the contrary10 replied his father1 8,i had a scolding40 8,a scolding60 exclaimed ,rollo4 8,yes10 replied his father2 8,i stepped out into the entry1 and asked the chamber-maid who was there1 if she would go and ask the landlord to come up into that room4 ,when he came1 ,i pointed to the wet and blackened ruins of the basket1 and said1-- 8#8,we came very near having a fire1 sir4'0 8,and what did he say80 asked ,rollo4 8,why1 he thought that it was my room1 and he was quite angry1 and began to scold me for being so careless as to leave that basket so near the fire40 8,and what did you say80 asked ,rollo4 8,nothing10 replied his father4 8,nothing60 exclaimed ,rollo4 8,no1 ,i did not say any thing at all4 ,i listened to hear all that he had to say1 and then ,i went away to my room40 8,why didn't you tell him80 said ,rollo4 8,i thought ,i would let him find out in his own way10 replied his father4 8,and did he find out80 said ,rollo4 8,yes10 replied his father4 8,he came to me after dinner1 and made a very humble apology4 ,he told me that he was very sorry for what he had said1 but that he supposed that that was my room40 8,and what did you tell him80 asked ,rollo4 8,i told him it was of no consequence1--and that a man who allowed himself to condemn before he made inquiry1 must expect to fall into some mistakes40 ,,questions4 ,under what circumstances did ,rollo find himself taking a walk with his father and mother8 ,what did ,rollo's father say was the peculiar and essential property of gunpowder8 ,which is more inflammable1 phosphorus or gunpowder8 ,how did ,mr4 ,holiday illustrate this8 ,what did ,mr4 ,holiday say about the expansive force of burning gunpowder8 ,by what process are fresh supplies of air furnished to fires8 ,why does the air which has once passed through the fire rise8 ,what is a chimney for8 ,would a chimney be necessary if a fire made no smoke8 ,relate the incident which occurred to ,mr4 ,holiday at the tavern4 ,what example of prudence and presence of mind is furnished by this case8 ,what example of hasty judgment8 ,what example of patient forbearance8 ,,chapter ,,viii4 ,,radiation ,,and ,,conduction4 ,there are two ways by which the heat or the warmth of one body passes off to the other bodies around it4 ,one is called radiation1 the other conduction4 ,rollo learned the meaning of these terms1 and the distinction between them1 under the following circumstances3-- ,one pleasant morning1 late in the autumn1 ,rollo's father said that he was going away on some business1 about fifteen miles1 and he told ,rollo's mother that1 if she would like to take a ride1 he should be very glad to have her go too4 ,she said that she should like to go very much1 and she proposed that ,rollo should go with them4 ,mr4 ,holiday had no objection to this arrangement1 and accordingly ,jonas was ordered to put both horses into the carryall1 and bring it up to the front door4 8,and1 on the whole1 ,jonas10 said ,mr4 ,holiday1 8you may go with us too1 and that will relieve me of all care of the horses40 ,there were two seats to the carryall4 ,rollo sat with ,jonas on the front seat1 and his father and mother behind4 ,they had a very pleasant ride in the forenoon1 but at noon it looked rather cloudy1 as if it might be going to rain4 ,rollo said he was afraid that it would rain before they should get home4 8,no matter for that10 said ,jonas4 8,why1 then we shall get wet10 said ,rollo4 8,no matter for that10 said ,jonas4 ,they were detained longer than they had expected to be at the place where ,mr4 ,holiday had his business to do1 so that it was rather late when they set out on their return home4 ,after they had rode about an hour1 it looked still more like rain1 and at length1 ,rollo felt a little drop upon his cheek4 ,he said1 in a complaining tone1-- 8,there1 ,jonas1 it is going to rain1 for it begins to sprinkle now40 8,rollo10 said ,jonas1 8when it rains1 the best way is to let it rain2 for there is no knowing what good may come of it40 8,i don't think any good can come to us10 said ,rollo1 8to be out in this storm1 and night coming on4 ,i should think that you might drive faster40 ,jonas was driving pretty fast1 and the rattling of the wheels made so much noise1 that ,rollo's father and mother did not hear what he and ,jonas were saying4 ,nor did ,rollo hear the conversation in which his father and mother were engaged4 ,they were1 in fact1 discussing the expediency of not attempting to get home that evening1 but of stopping1 instead1 at a little village a few miles before them4 ,as it was growing cold and late1 and as there was every appearance of an approaching storm1 they concluded to do this2 and so1 to ,rollo's surprise1 when they came into the village1 his father said to ,jonas1-- 8,jonas1 you may drive up to this hotel on the right2 we are going to stop here for the night40 ,jonas and ,rollo were both glad to hear this4 ,jonas drove up to the door1 and ,rollo and his father and mother were soon transferred from their places in the carryall1 which were beginning to be cold1 and cheerless1 and uncomfortable1 to a pleasant little parlor1 with a bright fire in the fireplace1 and a table in the middle of the room spread for tea4 ,now1 it happened that1 in this little parlor1 the fire was made in what might be called a fireplace-stove1 that is1 a stove made in the form of a fireplace4 ,it stood out upon the hearth1 and from the top of it a stove pipe ascended towards the top of the room1 and there passed back into the chimney4 ,the fire was not built in this room until the party which was to occupy it arrived1 but the room became warm very quick4 ,rollo was surprised that the room became warm so quick1 and his father said that such an arrangement as that1 namely1 a stove standing out upon the hearth1 with a pipe above1 warmed a room very quickly2 and one reason was1 that it operated by conduction as well as by radiation1 whereas a fire in a common fireplace could only warm the room by radiation4 ,then ,rollo wanted to know what conduction and radiation meant4 ,his father explained them to him while they were waiting for the tea to be brought in4 8,there are two ways by which heat moves10 said his father4 8,one way is by shooting swiftly through the air like light4 ,hold your hand up before the fire40 ,so ,rollo held his hand up before the fire as his father had directed4 8,do you feel the warmth of the fire upon your hand80 8,yes1 sir10 said ,rollo4 8,the heat comes from the fire to your hand very swiftly through the air1 and makes your hand feel warm40 8,how do you know it comes so swift1 sir80 said ,rollo4 8,i will show you10 said his father4 ,so his father looked about the room1 and he saw a large book lying upon a table between the windows4 ,he got the book1 and brought it to the fire4 8,now10 said he1 8,i will hold the book between your hand and the fire4 ,then the heat cannot come to your hand40 ,so ,mr4 ,holiday held the book between ,rollo's hand and the fire1 and ,rollo said that he could not feel the heat4 8,now10 said his father1 8,i will take the book away suddenly1 and we will observe what will be the effect4 ,if the heat moves slowly through the air1 it will be some time before you begin to feel the warmth2 but if it shoots through to your hand quick1 you will feel it immediately40 ,so saying1 ,mr4 ,holiday suddenly withdrew the book4 8,yes1 sir10 said ,rollo2 8,i feel it immediately40 ,rollo's father then told him to go back from the fire as far as he could go1 and still feel the heat upon his hand1 and then he interposed the book between the fire and his hand just as before4 ,rollo still found that he could feel the heat from the fire instantly1 after his father took the book away4 8,now1 that is radiation10 said ,mr4 ,holiday4 8,radiation80 replied ,rollo4 8,yes10 said his father4 8,heat radiates from a fire1 in all directions1 through the air4 ,heat radiates1 too1 from all bodies that are hot1 or warmer than the air around them4 ,go and hold your hand near the stove pipe1 and see if you can feel the heat radiating from the stove40 ,rollo did so4 ,he said he could feel the heat very plainly1 though he had to hold his hand nearer than was necessary when he was feeling the heat of the fire4 8,yes10 said his father2 8that is because the pipe is not so hot as the fire4 ,if the pipe was as hot as the fire1 it would be red hot1 and then you could feel the radiation as far as you do that of the fire4 ,however1 there is some radiation1 though the pipe is not very hot4 ,there is always radiation when the thing is warmer than the air around it4 ,there is radiation from your face40 ,here ,rollo put his hand up towards his face1 to try whether he could feel the radiation4 8,you can't feel it very well with your hand10 said his father1 8because your hand is warm1 and so that radiates too4 ,but if you hold your hand up very near to your face1 perhaps you will feel both to be warmer1 for your hand will radiate to your face1 and your face will radiate to your hand40 ,rollo then put his hand up very near to his cheek1 and1 after holding it there a minute1 he said that he perceived that it felt warm4 8,at any rate10 said his father1 8you understand what radiation is4 ,the heat that comes from the sun is radiated40 8,yes1 father10 said ,rollo1 8,i understand what radiation is2 now tell me about conduction40 8,very well10 said his father2 8suppose you had an iron crowbar here1 and should put one end into the fire1 among the burning coals1 and let it remain there while you took hold of the other end with your hand4 ,now1 the heat would gradually extend along the bar1 from the hot end in the fire towards your hand1 through the substance of the iron40 8,would it1 sir80 said ,rollo4 8,yes10 replied his father2 8so that at last the end in your hand would begin to feel hot4 ,did you never try it with a pin in the lamp80 8,yes1 sir10 said ,rollo2 8if ,i hold a pin in the lamp1 it burns my fingers40 8,the heat10 said his father1 8is conducted along through the pin to your fingers4 ,there is a radiation from the lamp at the same time1 but the radiation is not enough to burn you at that distance4 ,that is1 if you hold your finger near the lamp1 as near as the length of a pin1 you would feel the warmth produced by the radiation of the heat through the air1 but it would not be enough to burn you4 ,but when you take a pin1 and put one end into the flame1 it conducts off a great deal more heat than will come by radiation1 and your fingers are burned4 ,but then it takes more time for the heat to come along the pin1 than for it to come through the air4 ,thus1 in that case1 the heat that is radiated comes very quick1 though there is but little that comes2 while that which is conducted comes slowly1 but in a great quantity40 8,it burns me pretty quick1 father10 said ,rollo4 8,yes10 replied his father1 8because the pin is very short4 ,but if it was a knitting-needle1 or an iron rod longer still1 it would take some time for the heat to pass from one end to the other4 ,heat moves quickly by radiation1 and slowly by conduction4 8,now1 if you should go to the stove10 continued ,mr4 ,holiday1 8and put your hand upon it1 you would burn it by conduction2 that is1 the heat would be conducted through the iron to your hand4 ,but if you should hold your hand before the fire so near that the heat would come from the coals through the air to it1 burning you1 then you burn your hand by radiation4 8,but you must understand10 continued his father1 8that there may be conduction from air1 as well as from iron4 ,if you come into a room which is very warm1--that is1 where all the air in it is very warm1 although the fire may be gone out1--then the warmth you feel comes to your face and hands by conduction from the air which touches your face and hands1 just as your hand would be burned by touching the iron that is hot4 ,but if you come into a room where the air is not very warm1 but where there is a great blazing fire1 then you feel warmed by radiation4 ,do you understand this80 8,yes1 sir10 said ,rollo4 8,i believe ,i do40 8,i will ask you some questions then1 and see if you can answer them4 ,when we toast bread1 is the heat applied by radiation or conduction80 8,by----radiation1 sir10 said ,rollo4 8,yes2 when we bake bread in an oven1 is it by radiation or conduction80 8,by conduction10 said ,rollo4 8,yes10 said his father1 8because you perceive that the fire has all been taken out from the oven1 and the bread is baked by the heat of the air which surrounds it4 ,i don't know but that there may be also some radiation from the sides of the oven1 which are very hot2 but no doubt a great deal of the heat is conveyed to the bread by conduction4 8,when things are boiled1 is the heat applied by radiation or conduction80 said his father4 8,by conduction from the water10 said ,rollo4 8,yes2 and when they are roasted80 8,by radiation10 replied ,rollo4 8,very well10 rejoined his father4 8,i believe you understand the distinction very well4 ,some other time1 ,i will tell you more about both radiation and conduction4 ,but now ,i see the tea is coming in40 ,rollo looked around1 and saw a girl coming in1 bringing a waiter with two tea-pots upon it1 and a plate of toast covered with a bright cover1 and some other things4 ,she put them all upon the table1 and then said to ,mr4 ,holiday1-- 8,your tea is ready1 sir40 ,so ,rollo and his father and mother took their places at the tea-table to eat their supper4 ,nothing more was said on the subject1 until1 just before they rose from the table1 ,rollo happened to think that his father had said1 at first1 that a stove like the one in that room warmed the room both by radiation and conduction1 and he asked his father how that was4 8,in the first place10 replied his father1 8it warms the room by radiation just like any other fire1 as you observed by holding your hand before it4 ,but then it also warms the air in the room by conduction1 in this way2 the heat of the fire heats the iron of the stove and of the pipe4 ,the heat is conducted through the iron to the outside1 and there some of it radiates1 and the rest is conducted into the air which happens to touch it4 ,exactly as if you put your hand against the stove pipe1 the heat is conducted through to your hand4 ,so it is conducted to the air1 which touches the pipe4 ,this air becomes heated1 and swells1 and so grows light1 and rises out of the way1 and more cold air comes in to the stove pipe1 and gets heated in the same way by conduction4 ,so the air is continually coming up against the stove and pipe at all parts1 and it gets heated by conduction1 and then rises and floats away over the room1 and thus helps warm the room4 ,but in a common fireplace all the heat which is conducted off goes back among the bricks of the chimney1 and does not help warm the room4 ,if we had a light tuft of down or cotton1 and were to put it near the pipe1 perhaps it would be carried up to the top of the room1 by the current of air which is heated by conduction of the pipe40 8,i wish ,i had a tuft to try it10 said ,rollo4 8,it would be a very good experiment40 ,rollo had no tuft1 but he had that evening an opportunity to witness the effect of the ascending current of heated air1 in a way which he did not anticipate2 for1 after tea1 they had the table out1 for ,rollo's father to do some writing1 while his mother sat in a rocking-chair near1 reading4 ,rollo wanted to write1 and so his father let him have a pen and ink4 ,he said that he would write a little note to his cousin ,lucy4 ,it was a very small note1 on a little piece of paper1 and when he had written down one side1 he undertook to dry what he had written by means of the radiation from the lamp1 and accordingly held up his paper very near the flame of the lamp1 upon one side4 ,the writing1 however1 did not seem to dry very fast1 and in changing the position of it1 he held it over the flame1 though so high that he thought that there was no danger of burning it4 ,but the current of heated air which rises upward from a fire1 even so small a fire as the flame of a lamp1 is hotter1 and rises higher1 than most children would suppose4 ,at any rate1 before ,rollo was aware of the danger1 his note was on fire1 and he was obliged to turn around suddenly1 and throw his paper upon the hearth1 to escape burning his fingers4 ,,questions4 ,in what two ways is heat conveyed from one body to another8 ,relate the circumstances which led ,rollo and his father and mother to spend the night at a tavern4 ,what sort of a stove did they find in the little parlor8 ,what is radiation of heat8 ,how did ,mr4 ,holiday demonstrate it to ,rollo8 ,how did he prove that heat passes swiftly when it is radiated8 ,how did ,mr4 ,holiday explain and illustrate conduction8 ,by which mode is the greatest quantity of heat conveyed8 ,which communicates heat most rapidly8 ,what were some of the questions which ,mr4 ,holiday put to ,rollo to ascertain whether he understood the distinction8 ,what incident occurred to ,rollo in the evening8 ,,chapter ,,ix4 ,,radiation4 ,when ,rollo awoke the next morning1 he found that the storm was over1 and he was very glad to see that there was a prospect of a pleasant ride home4 ,he heard a sound as of voices in the yard1 under the window of the chamber where he slept4 ,he looked out1 and saw a large yard near the stables1 with a pump upon one side of it4 ,before the pump was a large trough1 nearly full of water4 ,at one end of the trough there was a cow drinking4 ,jonas was coming from one of the stables leading a horse4 ,he was going to let him drink4 ,there was a boy at the pump1 at work pumping water1 to keep the trough full while the animals were drinking4 8,i mean to go down there10 said ,rollo to himself4 ,he accordingly finished dressing himself as soon as he could1 and went down into the yard4 8,let me pump10 said ,rollo to the boy4 8,well10 said the boy1 8and ,i'll go and be putting down the hay40 ,so the boy left ,rollo at the pump1 and went off towards the stable4 8,what does he mean by putting down the hay80 said ,rollo to ,jonas4 ,for ,jonas had by this time come to the trough1 and his horse was beginning to drink4 8,you pump too fast1 ,rollo10 said ,jonas2 8you make the trough run over40 8,well10 said ,rollo1 8and does that do any hurt80 8,no10 replied ,jonas1 8only it exhausts your strength to no purpose1 and by and by you'll be tired1 and can't pump at all40 8,then ,i'll pump slower10 said ,rollo4 ,so ,rollo began to pump more slowly4 ,presently the cow went away1 and two oxen came1 one after the other1 from the barn4 ,the boy had let them out4 ,rollo went on talking with ,jonas1 pumping very slowly indeed1 so that he did not supply water as fast as the animals drank it4 ,the surface of the water in the trough began to subside1 and then ,jonas called upon ,rollo to pump faster4 8,o dear me1 ,jonas60 said ,rollo2 8you are very hard to be suited40 8,yes10 replied ,jonas1 8,i am4 ,if a boy undertakes to do any thing1 ,i want him to do it right1--and that is hard4 ,there are two wrong ways to do a thing1 and one right way4 ,first you pump too fast1 and then too slow2 whereas ,i want you to pump just right40 8,and how should ,i pump80 said ,rollo4 8,why1 ,i want you to have the pumping and the drinking exactly in equilibrium40 8,in equilibrium80 repeated ,rollo4 8,yes10 replied ,jonas2 8that is1 you must supply water from the pump just as fast as the horse and the oxen drink it1 and so keep it at the same level in the trough4 ,thus you'll keep the supply and the consumption in equilibrium40 8,well10 said ,rollo4 ,so he pumped a little faster1 until he got the trough nearly full1 and then he noticed the point on the inside of the trough where the surface of the water stood4 ,when he found that the water was rising above that point1 he relaxed his efforts a little until it sank again2 and when he found that it was falling below1 he pumped harder4 ,thus he contrived to keep the supply very nearly equal to the consumption4 ,illustration3 ,,rollo ,,warming ,,his ,,hands ,,by ,,the ,,fire--,page #acc4 ,it was pretty cold that morning1 and1 after ,rollo had pumped for some time1 his hands became cold4 ,so he went into the house4 ,he found his father and mother in the little parlor where they had been the evening before4 ,there was a good fire in the stove1 and ,rollo held his hands up before it1 and warmed them by the radiation4 ,the breakfast-table was set1 and before long a girl came in bringing in the breakfast4 ,among the other things was a little copper tea-kettle1 with a heater to set it upon1 in order to keep the water hot4 ,the heater was made in this way3 ,there was a sort of pan of planished tin1 large enough for the tea-kettle to be set into it4 ,in the middle of this pan was a round cavity1 with a bottom and sides of sheet iron1 and there was a piece of cast iron1 about half an inch thick1 made to fit into this cavity4 ,this piece of cast iron was to be heated in the fire1 and then put into its place with the tongs1 and then the tea-kettle was to be put over it1 in the pan1 in such a manner that the bottom of the tea-kettle rested upon the top of the heater4 ,rollo was very much interested in this apparatus4 ,it was placed upon a corner of the table1 near the waiter1 and ,rollo's attention was first attracted to it by observing that the tea-kettle continued to boil a little on the table4 ,he could not think what made it boil2 and1 as they were about sitting down to the table1 his father began to explain it to him4 8,the heater1 you observe10 said he to ,rollo1 8furnishes heat to the tea-kettle by conduction1 to supply the waste by radiation40 8,what1 sir80 said ,rollo4 ,he did not understand his father very well4 8,why1 the tea-kettle loses its heat by radiation principally1 and the heater supplies it by conduction1 and so one restores what is lost by the other40 8,i don't understand it1 exactly10 said ,rollo4 8,well10 said his father1 8,i'll explain it to you presently1 alter we have taken our seats at the table40 ,accordingly1 when they were all seated at the table1 ,rollo asked his father about the operation of the heater and the tea-kettle4 8,well10 replied his father1 8,i will explain it to you4 ,it is a very good apparatus to illustrate the subject4 ,the tea-kettle is a radiator1 and the heater is a conductor1 and so they show both modes of conveying heat4 8,for10 continued his father1 8as the sides of the tea-kettle do not come in contact with any thing but the air1 they do not conduct away the heat much2 for the air does not take heat easily by conduction4 ,but the tea-kettle radiates heat continually4 ,if you put your hand near it1 you will feel the heat passing off into the air all around40 ,here ,rollo1 who was seated not very far from the tea-kettle1 put out his hand towards it to feel the radiation4 8,the tea-kettle would conduct away the heat very fast1 if there was any thing touching it all around1 which would take heat easily by conduction40 8,how fast80 said ,rollo4 8,why1 if you were to put your hands to it1 clasping it all around1 the heat would be conducted very fast into your hand1 and you would be burned4 ,your hands would receive the heat readily by conduction1 but the air does not4 8,and the tea-kettle10 continued his father1 8does not radiate the heat very fast1 because it is a bad radiator4 ,it is made so on purpose40 8,what do you mean by a bad radiator1 father80 asked ,rollo4 8,why1 all white1 and bright1 and polished surfaces radiate very little1--and all dark1 and dull1 and rough surfaces radiate very fast4 ,so the bright surfaces are called bad radiators1 and those that are of dark color and dull1 are called good radiators4 ,a bright tea-pot1 made of metal1 is a bad radiator1 and that makes a good tea-pot40 ,rollo laughed4 8,its being so bright prevents its radiating the heat of the water within it very fast away1 and so the water keeps hot longer4 ,but a stove pipe1 which is of dark color1 and not polished1 is a good radiator4 ,they make them so on purpose4 ,a stove pipe made of some bright metal would look a great deal better1 but it would not warm the room so well40 8,but1 father10 said ,rollo1 8this copper tea-kettle isn't white1 nor very bright40 8,no10 said his father1 8it is not very bright3 but the surface is polished1 you see1 somewhat1 and this prevents its radiating much4 ,still it radiates more of the heat than it would if it was of silver1 and polished as bright as possible4 ,but a common iron tea-kettle1 black upon the outside1 would radiate heat much faster than this one4 8,there is another thing for you to understand and remember10 continued his father2 8and that is1 that those substances which radiate heat best1 also receive heat by radiation the best40 8,i don't know exactly what you mean by receiving heat by radiation1 sir10 said ,rollo4 8,suppose10 said his father1 8that we were to cut out a square piece of sheet iron1 such as the stove pipe is made of1 as large as the palm of my hand1 and also a piece of silver1 like that which a tea-pot is sometimes made of1 and have it polished as perfectly as possible4 ,suppose1 then1 that we were to carry both of these out1 and lay them down in the sun4 ,or suppose we hold them up before the fire1 so that they would receive the radiation from the fire4 ,now the iron plate would receive the rays of heat more rapidly than the other1 and become hot the soonest40 8,would it1 sir80 said ,rollo4 8,yes10 replied his father2 8or1 if you were to lay them down in the sun out of doors1 the effect would be the same40 8,i wish we had such pieces to try it10 said ,rollo4 8,did not you ever observe how cold bright brass andirons are1 long after the fire has been built in the fireplace80 8,i have10 said ,rollo's mother4 8,so have ,i1 sir10 said ,rollo4 8,it is because they are polished1 and so are neither good to radiate nor to receive radiation4 ,there is another way by which the same principle is illustrated in the spring of the year1 when the snow is melting away4 ,every little leaf1 or stick1 or insect1 that happens to light upon the snow1 soon sinks down40 8,yes1 sir10 said ,rollo1 8the bees do4 ,last spring1 when ,i went out in the pasture on the crust one morning1 ,i found a great many bees all down at the bottom of little holes in the snow4 ,i couldn't think how they happened to get into those little holes40 8,the holes were made by the heat of the sun10 said his father1 8after the bee fell4 ,the bee is of dark color1 and his body receives the radiation of the sun much better than the snow1 which is polished40 8,the snow polished80 said ,rollo4 8,yes10 said his father4 8,the snow is composed of flakes1 and the flakes of a great number of little needle-like crystals1 and all these crystals are polished1 so that they do not radiate well1 nor receive radiation well4 ,therefore the heat of the sun has not much effect upon a pure snow bank4 ,but the body of the bee is a good radiator1 and also a good receiver of radiation4 ,so it gets warm1 and that melts the snow under it1 and then it sinks down1 so that after a time it gets down to the bottom of a little pit1 which it has made itself40 8,that's very curious10 said ,rollo4 8,yes10 said his father2 8and it is so with every little stick1 or sprig1 or dry leaf1 which happens to fall upon the snow4 ,you could see the effect more distinctly still1 if you were to put a bright piece of tin1 and a piece of sheet iron1 like stove pipe of the same size1 upon the snow in the sun4 ,the iron would receive the radiation1 and get warm1 and would sink down in the snow1 but the tin would not receive the radiation40 8,wouldn't it receive any at all80 asked ,rollo4 8,yes10 replied his father1 8it would receive some1 ,i've no doubt1 but perhaps not more than the snow itself would on each side of it2 and so the snow that was all around it would melt away as fast as that which was under it1 and thus would not make any pit or depression in the snow1 as the black iron would40 8,but ,i have observed10 said ,rollo's mother1 8that1 in the spring of the year1 wherever there are chips or shavings upon the snow1 in the yard1 it does not melt away under them1 as fast as it does in other places40 8,yes1 father10 said ,rollo1 8and hay too4 ,last year1 there was some hay left at the post where ,jonas tied the horse2 and1 after the snow was all gone from the rest of the yard1 ,i raked that hay away1 and ,i found a great deal of ice under it40 8,yes10 said his father1 8,i've no doubt of it4 ,that depends upon another principle4 ,but we shall not have time to talk about that now2 ,i will tell you about it after we get into the carryall40 ,in fact1 they had by this time nearly finished their breakfast2 and so1 after a few minutes more1 they rose from the table1 and ,rollo went out to tell ,jonas that they should be ready to go whenever the horses were harnessed4 ,in about fifteen minutes1 ,jonas drove up to the door1 and they got into the carryall and set out for home4 ,,questions4 ,what did ,rollo observe in the yard when he looked out the window the next morning8 ,what were the difficulties in ,rollo's pumping8 ,what apparatus attracted ,rollo's attention at the breakfast-table8 ,describe its construction4 ,how did ,mr4 ,holiday explain the operation of it8 ,what sort of surfaces radiate fast8 ,what sort of surfaces radiate slowly8 ,what examples did ,mr4 ,holiday mention to illustrate this8 ,describe the appearances on the snow in the spring of the year1 which were mentioned by ,rollo4 ,,chapter ,x4 ,,conduction4 ,very soon after ,jonas had driven out of the village1 ,mr4 ,holiday went on with his explanation4 ,rollo sat1 as before1 upon the front seat2 but1 by turning a little in his seat1 he could hear what his father said very well4 8,let us see10 said his father2 8where did we leave off80 8,about the chips10 said ,rollo's mother4 8,and the hay10 said ,rollo4 8,yes10 said his father4 8,we'll take the case of the hay4 ,should you think1 from what ,i told you1 that hay would be a good or bad radiator80 8,good10 said ,rollo4 8,why80 asked his father4 8,because10 replied ,rollo1 8it is not bright and polished40 8,right10 said his father4 8,and should you think that it would be a good or a bad receiver of radiation80 8,good10 replied ,rollo again4 8,yes10 added his father1 8because all those surfaces which are good radiators1 are good receivers of radiation40 8,only10 said ,rollo1 8the snow doesn't melt under it4 ,it all turns to ice40 8,true10 said his father4 8,how thick was the hay in the place that you refer to8 that is1 how much was there1 and how thick a covering did it make upon the ground80 8,not very thick10 replied ,rollo4 8,an inch80 asked his father4 8,o1 yes1 sir1 more than an inch40 ,here ,rollo held his two hands at a little distance apart1 in order to show his father how thick the covering of hay was4 ,it might have been three or four inches1 though it is not probable that ,rollo's recollection of it was very exact4 8,very well10 said his father2 8we will call it three inches4 ,now1 you must remember that the sun shines only upon the upper surface of the hay1 and1 if it is ever so good a receiver of radiation1 it is only the upper surface that can be warmed by the direct rays4 ,in order to melt the snow1 the hay has not only got to receive the heat from the sun by radiation on the upper surface1 but it has also got to convey it down through this space of three inches by conduction4 ,now a substance may be a very good radiator1 and a very good receiver of radiation1 while it is a very bad conductor4 ,and this is the case exactly with hay4 ,it receives radiation very well1 and so the top gets warm under the rays of the sun2 but it conducts very slowly1 and so the bottom keeps cool1 although the top is warm4 ,so1 you see1 a single blade of hay1 laid upon the snow under the rays of the sun1 would make the snow melt the faster2 but a layer of it three inches thick would keep it from melting4 ,a layer of two feet thick would perhaps keep it from melting all summer40 8,why1 father10 said ,rollo1 8,i should think it would make it warmer40 8,no10 said his father2 8it would keep the warmth from getting to it1 because it is a slow conductor4 ,if any thing already warm is covered up in hay1 it keeps it from getting cool2 if any thing already cool is covered up1 it keeps it from getting warm40 8,what things are good conductors80 asked ,rollo's mother4 8,the metals10 said his father1 8are the best40 8,if they are polished80 asked ,rollo4 8,whether they are polished or not10 replied his father4 8,i do not know that that makes any difference4 ,because1 you see1 in being conducted1 the heat moves through the middle of the body1 and not along its surface so much2 and ,i don't know that the character of the surface is of much importance4 ,some metals conduct better than others4 ,the philosophers have a curious kind of an instrument to show the different conducting powers of different substances40 8,what is it1 father80 said ,rollo4 8,why1 they have a small iron plate----0 8,round80 asked ,rollo4 8,no1 square10 replied his father4 8,i thought plates were always round10 said ,rollo4 8,no10 replied his father2 8a plate1 in philosophical language1 is any flat and comparatively thin piece of metal1 or other such substance1 whatever its shape may be4 ,this plate that ,i was speaking of is square1 or oblong1--,i believe it is oblong1--and it is about as large as my hand1 and perhaps half an inch thick4 8,in this plate10 continued his father1 8there are drilled a number of little holes40 8,how many1 sir80 asked ,rollo4 8,why1 perhaps eight10 said his father4 8,they are in a row1 running along the middle of the plate4 ,the holes are about a quarter of an inch in diameter40 8,how much is that80 asked ,rollo4 8,why1 ,i should think a common lead pencil might be a quarter of an inch in diameter4 ,the holes are of such a size that you could just put a lead pencil in before it is cut40 8,are the holes bored entirely through the plate80 asked ,rollo's mother4 8,no10 replied his father1 8a little more than half through40 8,then10 continued he1 8they have a number of little rods made of different substances1--such substances as they wish to try1 in respect to their conducting power4 ,one is made of brass1 one of iron1 one of glass1 one of wood1 c41 and these are fitted into the holes4 ,that is1 one end of each rod is made just large enough to go into its hole and take out1 and yet not be loose in it4 8,the upper ends of these rods are hollowed out a little1 so as to form small cavities or cups1 to put some phosphorus into40 8,what is that for80 asked ,rollo4 8,i'll tell you10 said his father4 8,when they are going to use the instrument1 they put all the rods into their sockets1 and a little bit of phosphorus into the top of each one1 in the cavity4 ,each piece of phosphorus is about as big as the head of a pin4 ,now1 when these rods are all arranged in this way1 the whole apparatus is put upon some hot place1 where the whole plate will be heated alike1 as1 for example1 upon the top of a stove4 ,the heat from the stove is conducted into the iron plate2 from the iron plate it is conducted into the ends of the rods which are in the sockets2 thence it is conducted up the rods towards the phosphorus at the tops of them1 only it goes up much more slowly through some than through others4 ,and we can tell which rod conducts the heat the most rapidly1 for the phosphorus upon the top of that rod will be the first to take fire40 8,will the phosphorus take fire80 said ,rollo4 8,yes10 replied his father4 8,if the stove is pretty hot1 enough heat will be conducted up the rods to set the phosphorus on fire4 ,it will look as if the tops of the rods were getting on fire4 ,first one will blaze up1 and then another1 and then another1 according as the rods convey the heat up more or less readily4 ,perhaps the phosphorus upon the top of the glass or wooden rod will not take fire at all40 8,i should think10 said ,rollo1 8that the heat would get up some time or other1 if it went up ever so slowly40 8,no10 said his father1 8for some of the heat is conveyed off into the air1 up and down the sides of the rods2 and so1 if the rods are very long1 or if they are very bad conductors1 they would radiate the heat from their sides so fast that not enough would get up to the top to set the phosphorus on fire40 8,what is the slowest conductor of heat80 said ,rollo4 8,the air is a very slow conductor10 replied his father1 8if we can only keep it still4 ,so is wood4 ,a heap of shavings is a very slow conductor1 because it consists of wood and air together40 8,how is that80 said ,rollo4 8,why1 the little interstices between the shavings are all filled with air2 and the heat1 in passing through1 has to go through the thickness of a shaving first1 and then through a small space of air2 then through another shaving1 and then a little more air2 and so it works its way along very slowly1 and with great difficulty4 ,therefore1 if any thing is covered with shavings1 heat neither gets into it nor out of it very easily4 ,it is the same with hay40 8,only the blades of hay are not wood10 said ,rollo4 8,not exactly10 replied his father1 8and yet they are very near it4 ,the fibres of the stems of grass are very similar to the fibres of wood4 ,at any rate1 they are both slow conductors2 so that hay1 like shavings1 will keep the heat from coming away from any thing that is hot1 and from getting into any thing that is cool40 8,it is very strange10 said ,rollo1 8that the same thing should be good to keep things hot1 and to keep them cool too40 8,i don't know10 said his father1 8that it is very strange1 if we consider how it operates4 ,it keeps the heat from passing either way4 ,hay has no warmth in itself4 ,if you put hay about your feet when you are riding1 it will keep them warm1 because the warmth is in your feet already1 and the hay keeps it from going away4 ,on the other hand1 if you put hay around a lump of ice1 it will keep it cool1 because the ice cannot melt unless some heat gets into it from the sun and air1 and the hay impedes the progress of the heat in going in1 as well as in coming out4 ,it is just so with furs or blankets4 ,they don't make things warm4 ,they only keep them from getting cold40 8,but1 father10 said ,rollo1 8if my feet were very cold1 and ,i were to wrap them up in blankets1 wouldn't it make them grow warm80 8,yes10 said his father1 8they would grow warm1 but not because of any warmth in the blankets4 ,the warmth would be produced in your body by the blood1 and the blankets would keep it from escaping4 ,that is all4 ,blankets and furs would be the best things to put up ice in1 to keep it cool4 ,they keep the heat from going off from our bodies1 and so1 in the same way1 they would keep heat from going in from the sun and air to the ice40 8,why don't they keep ice so1 then80 said ,rollo4 8,because it would be very expensive4 ,shavings1 and tan1 and such things1 will do nearly as well1 and they are a great deal cheaper4 ,branches of trees would do very well1 if the leaves were on4 ,once ,i heard of a boy who made an ice-nest1 that kept the ice all summer40 8,how did he do it1 sir80 said ,jonas4 8,why1 he found a little hollow on the north side of a hill1 and he covered the bottom of it with hemlock branches a foot thick4 ,then he piled up square blocks of ice upon the branches till he made a pyramid of ice as high as his head1 and as large on the bottom as a large table4 ,then he heaped up straw and shavings all around it till the ice was covered very thick4 ,he also contrived to put some sheets of bark over it1 to keep the rain off2 and thus he kept his ice nearly all summer40 8,i should like to try it10 said ,jonas4 8,it would be better for you to make a little building10 said ,mr4 ,holiday2 8that would be much more convenient to get into4 ,you would only have to make the walls double1 and fill the space between with tan1 or shavings1 or straw1 or any other substance like that1 to keep the heat out40 8,let us do it1 ,jonas10 said ,rollo4 8,i should like a little ice-house very much40 ,rollo's mother said that she wished ,jonas would2 so it was settled that he was to try and see if he could make an ice-house4 ,,questions4 ,what phenomenon that ,rollo had observed was it that ,mr4 ,holiday was going to explain when they were seated in the carryall8 ,did they conclude that hay would be a good or bad radiator8--a good or bad receiver of radiation8 ,how1 then1 did ,mr4 ,holiday account for the snow and ice melting so slowly under it8 ,what was the object of the philosophical instrument constructed8 ,what are some of the best conductors of heat8 ,what substances are slow conductors8 ,describe the plan which the boy devised for keeping ice all summer4 ,,chapter ,,xi4 ,,the ,,ride ,,home4 ,after the conversation recorded in the foregoing chapter1 the party in the carryall rode on for some time in silence4 ,they were going towards the east1 and the morning sun shone very pleasantly upon them1 so that it was not cold riding4 ,the air had been frosty early in the morning1 but the rays of the sun brought so much warmth with them that they enjoyed their ride very much4 ,after some time1 ,rollo's father began to speak again of the conductive powers of different substances1 thus3-- 8,i think it probable that the fibres of wool and of fur are better non-conductors of heat than the fibres of wood1 and grass1 and straw1 and other vegetable substances40 ,rollo did not at first understand what his father meant by non-conductors4 ,he had not heard him use that term before4 ,so he asked him what it meant4 ,his father told him that1 as people often wanted to employ substances which would not easily conduct heat1 they had frequent occasion to use a word adapted to denote such substances as were suitable to such a purpose1 and that non-conductors was the term which was so used4 8,there are two reasons10 said he1 8why ,i think it probable that the fibres of the covering of animals are better non-conductors--that is1 that they conduct heat more slowly--than vegetable fibres4 ,i should like to have you tell me whether you think they are satisfactory40 8,well1 sir10 said ,rollo1 8if you will tell us what the reasons are40 8,first1 tell me of all the substances that you can think of which are composed of animal fibres40 8,fur10 said ,rollo1 8and wool40 8,and hair10 said his mother4 8,yes10 said his father1 8and woollen cloth1 and blankets1 and carpets1 and flannel1 are made of such animal fibres4 ,now1 can you tell me of any substances which are composed of vegetable fibres80 8,hay10 said ,rollo2 and then he paused4 ,he could not think of any others4 8,cotton10 said his father1 8and flax4 ,they are vegetable fibres2 and cotton cloth1 and linen1 and paper1 are fabrics made of vegetable fibres4 ,now1 there are two reasons which make me think that the animal fibres are better non-conductors than the vegetable4 ,one is1 that they are expressly intended for non-conductors1 and therefore would probably be so formed as most perfectly to answer their design4 8,for you see10 continued ,mr4 ,holiday1 8that the wool1 and the fur1 and the hair1 of animals is generally intended as a covering to protect them from the cold4 ,that is1 it is intended to keep the heat of the body from passing off1 and being wasted in the air4 ,therefore they must be non-conductors of heat1 in order to answer this design4 ,now1 we find that everything in nature is admirably adapted to answer its design1 and therefore we should expect that these substances1 which are expressly intended to confine heat1 would be the best non-conductors of heat in nature4 ,that is one reason40 8,i think it is a very good reason10 said ,rollo's mother4 8,so do ,i10 said ,rollo4 8,the other reason is this10 continued ,mr4 ,holiday4 8,all the substances made of the vegetable fibres feel colder to the touch in cold weather than those made of animal fibres4 ,for example1 suppose you were to go1 in a very cold night1 into a room where there was no fire1 and put one hand into a bed between the sheets1 and the other between the blankets1--which would feel the coldest80 8,the sheets10 said ,rollo1 8a great deal40 8,and the reason why they would feel coldest must be10 said ,mr4 ,holiday1 8that they conduct away the heat from your hand the fastest1 which shows that they are better conductors of heat4 ,if you were to put your hand upon iron in such a room1 it would feel colder still1 because the iron is a better conductor of heat than the vegetable fibres which the sheet is manufactured from4 8,in the same manner10 continued ,mr4 ,holiday1 8a bare wooden floor feels colder than one with a carpet upon it4 ,now1 in the case of a bare floor1 it is vegetable fibre which conveys away the heat1 and in the carpet1 if it is a woollen carpet1 it is animal fibre4 ,but a stone floor would feel colder than a wooden one40 8,a painted floor is very cold10 said ,rollo's mother4 8,yes10 said ,mr4 ,holiday2 8paint is made of some metallic preparation generally1 which is a better conductor than wood4 ,all the metals are much better conductors than wood4 ,that is the reason why they have wooden handles to tea-pots and other such vessels1 because a handle of metal would conduct so much heat from the hot water to the hand1 that we could not hold it40 8,yes1 sir10 said ,rollo2 8and the handle to the little tea-kettle at the tavern was a wooden one4 ,i did not know what it was for40 8,it was to keep the heat from coming to your hand when you pour out the water4 ,if the handle had been of copper1 it would have been necessary to have a non-conductor to put around it1 to keep the heat from coming out of the handle40 8,i never heard of such a thing10 said ,rollo4 8,haven't you80 said his father4 8,they make them sometimes1 and it is a very ingenious contrivance40 8,how do they make them80 said ,rollo4 8,they make them of some substance formed of animal fibre10 said his father1 8because that makes the best non-conductor4 ,the article1 when ready1 can be put upon any handle which is likely to get hot1 and1 being a non-conductor1 it stops the heat from coming from the handle to your hand4 ,you can take up any hot thing by means of it1--unless it is hot enough to burn the animal fibre of which the non-conductor is composed40 8,i wish that ,i could see one10 said ,rollo4 8,well10 said his father1 8you can1 when you get home4 ,dorothy has got one1 ,i dare say40 8,dorothy60 repeated ,rollo4 8,yes10 said his father4 8,she calls it a holder40 8,o1 a holder10 said ,rollo4 8,i did not know you meant a holder40 8,why1 a holder is a non-conductor made of animal fibre1 and intended only to stop the passage of the heat from the iron handle to your hand40 8,i thought it was only to keep our hands from touching the handle40 8,no10 said his father1 8for an iron holder would do that2 but an iron holder would soon get hot1 and be of no use4 ,that is1 an iron holder would allow the heat to pass across very soon to your hand4 ,it must be a non-conducting holder4 8,and now10 continued ,mr4 ,holiday1 8you understand fully the philosophy of the copper tea-kettle4 ,the iron heater was the reservoir of heat4 ,as it was a good conductor1 it conveyed the heat rapidly into the bottom of the tea-kettle1 and so into the water4 ,the water1 being a good conductor1 conveyed the heat to the sides of the tea-kettle1 but they were made bright and polished1 so that they should not radiate it fast into the air4 ,still1 however1 they radiated the heat considerably2 but the waste was supplied by fresh heat from the heater4 ,at first1 the heat came faster from the heater than it was radiated from the sides of the kettle1 and so the water was made to boil4 ,but gradually the heater became less hot1 and so did not conduct heat so fast into the bottom of the tea-kettle1--until1 at length1 there was a time when the supply was just equal to the waste2 that is1 the heat was conducted in just as fast as it was dissipated by radiation1 and the temperature was kept at the same point40 8,that was something like my pumping1 ,jonas10 said ,rollo4 ,jonas nodded his head1 but did not speak1 as he did not wish to interrupt ,mr4 ,holiday4 8,at length10 he continued1 8the supply by conduction became less than the radiation1 and so the water began to cool1 and probably1 when we left the table1 the water had cooled considerably below the boiling point4 ,i think it likely it would have been better to have made the heater of some other substance than iron1--something that is not so good a conductor40 8,why1 sir80 asked ,rollo4 8,because10 said ,mr4 ,holiday1 8in that case it would not have communicated its heat so fast1 and so the supply would have lasted longer4 ,the iron is so good a conductor1 that at first it poured its heat up through the bottom of the tea-kettle in such quantities as to make the water boil4 ,this was more than was wanted1 and the heat at first was wasted4 ,in consequence of this1 after a time it became too cool1 and did not heat the water enough4 ,now1 if it had been made of something which was not a good conductor1 it would have parted with its heat more slowly at first1 and so the heat would have lasted longer40 8,yes1 sir10 said ,rollo2 8and what would have been good80 8,soapstone is a very good non-conductor10 said ,mr4 ,holiday4 8,but then1 perhaps soapstone would have got bruised and broken by constant use1 and by heating and cooling4 ,it isn't a very hard kind of stone4 ,i think it probable that iron is1 on the whole1 the best40 ,rollo learned nothing more on the subject of heat during this ride1 for very soon after this they began to draw towards home4 ,after they had arrived1 and the horses had been taken care of1 he and ,jonas went to look about for a good place to build the proposed ice-house4 ,,questions4 ,what two classes of non-conductors were the subjects of conversation on the ride home8 ,name some examples of animal fibres2 of vegetable fibres4 ,name some examples of fabrics composed of animal fibres2 of vegetable fibres4 ,which class of substances did ,mr4 ,holiday suppose were best non-conductors8 ,what was the first reason which he gave8--the second reason8 ,what did ,mr4 ,holiday say1 further1 in respect to the operation of the heater8 ,what was the point of analogy between the operation of the heater and ,rollo's pumping8 ,what was the objection to iron as the material for the heater8 ,what other substance did ,mr4 ,holiday suggest8 ,what objection to soapstone did he think of8 ,,chapter ,,xii4 ,,the ,,conflagration4 ,one night1 some months after the occurrences related in the last few chapters1 ,rollo had an opportunity of witnessing with ,jonas a great conflagration in the city4 ,this incident may very properly be described in this volume1 which relates to the phenomena of fire4 ,jonas and ,rollo had gone to the city on some business for ,mr4 ,holiday4 ,jonas's orders were to return that night if he could get through with his business2 if not1 to wait until the next day4 ,it happened that he could not get through with his business1 for the man whom he wished to see was not at home4 ,they said he would be at home that night1 and that ,jonas could see him early the next morning4 ,so they had to spend the night in the city4 ,they took a walk in the evening1 doing some errands1 and looking at the curious things in the shop windows2 and at last they went back to the hotel1 and retired to bed4 ,jonas had engaged a room for himself very near ,rollo's room4 ,rollo did not go to sleep for some time1 his mind being somewhat excited by the novelty of the scenes which he had been witnessing1 and by the strange place in which he was now trying to go to sleep4 ,at length1 however1 he got asleep1 and dreamed that he was buying a large and beautiful rocking-horse for ,nathan1 at one of the toy-shops in the city1--and was just mounting the rocking-horse to take a little ride himself1 when his visions were disturbed by hearing some strange1 confused1 and terrifying sounds4 ,he started up and listened4 ,there seemed to be a great sound in the street1 and a bright light was flashing and moving upon the wall over his head4 ,he also heard a noise at the door of his room2 and1 before he had time to consider what all this disturbance meant1 he heard ,jonas's voice1 saying in a gentle tone1-- 8,rollo40 8,what80 said ,rollo1 eagerly4 8,don't be frightened4 ,it's only a fire40 8,a fire6 where80 said ,rollo4 8,i don't know where it is10 replied ,jonas4 ,rollo listened a moment1 and he could hear the city bells ringing in very mournful and alarming tones1 some near1 and some at a distance4 ,there was one belonging to a church nearly opposite to the hotel1 which sounded very loud and near4 ,the flashing light upon the wall moved gradually along the room1 and then disappeared2 and soon after another came in on the opposite side1 and moved along the wall in the same manner4 ,rollo could hear the sound of a great uproar in the street below1 consisting of confused but loud and hoarse voices1 the heavy rattling of wheels1 and a bell which sounded in a very peculiar manner as it moved along the street1 as if it was rung by being jolted and jarred4 ,rollo and ,jonas went to the window to look out4 ,it was a dark and cloudy night1 and the window was very high from the street1 as ,rollo's room was in one of the upper stories of the house4 ,still they could look down upon the street below1 and see that it was filled with a torrent of men1 moving along in a hurried manner1 the whole mass being illuminated by great torches which some of the men carried in their hands4 ,they were dragging along a fire engine1 which thundered over the pavement as they ran1 in the most terrifying manner4 8,let's go and see the fire10 said ,rollo4 8,well10 said ,jonas1 8we might2 only perhaps there may not be any fire4 ,perhaps it is only an alarm40 8,no matter10 said ,rollo2 8let us go and see the alarm40 ,rollo knew that to witness the scene of noise and excitement in the street1 would interest him very much1 even if there was no house on fire4 8,well10 said ,jonas1 8dress yourself as quick as you can1 and ,i'll come in again when ,i'm ready40 ,jonas accordingly went out1 and finished making his preparations1 and then returned4 ,he required ,rollo to put on his great-coat1 for he said there would be danger of taking cold in standing still in the chill evening air1 to look at the fire if they should find one4 ,when they were ready1 they hurried down stairs4 ,the street seemed to be nearly still when they left ,rollo's room2 but1 when they issued from the hotel1 and stepped out upon the sidewalk1 they heard the sound of noise and uproar approaching again4 ,they looked in the direction from which the sound came1 and saw a great torch coming along the street1 which flamed1 and flashed1 and illuminated the pavements and the buildings on each side of it4 ,it was followed by a long1 double line of men and boys1 with other torches and lights at intervals1 pulling upon a rope2 and farther behind they heard a very heavy1 lumbering sound of wheels1 and a sort of confused roar of voices mingling with it4 ,it was another fire engine4 ,it approached with great rapidity1 and a crowd of men and boys attended and followed it1 so large as to fill the street full2 and1 brushing rudely by ,jonas and ,rollo on the sidewalk1 they filled the air with their loud but hoarse and hollow shouts4 8,ahead with her6 ahead with her60 ,rollo could not see the engine1 for the street was perfectly filled1 while it passed1 with a dense crowd of men and boys1 all running along by its side4 ,rollo thought that some of them would certainly get run over4 8,we'll go a little slower10 said ,jonas1 8till the engine gets by1 and then we shall have more room40 8,no10 said ,rollo1 8let's keep up4 ,i want to see where they will go40 8,well10 said ,jonas1----8,o1 there's the fire40 ,rollo looked forward where ,jonas pointed4 ,he saw1 through the opening between some tall buildings before them1 a faint light in the sky4 ,he saw it however only for a few moments2 for1 as they passed on1 the towering walls of the city buildings intervened again1 and hid it from their view4 ,pretty soon1 however1 at a turn of the street they came in view of the light again2 and now it looked much brighter than before4 ,it spread upwards1 in fact1 and illuminated a considerable part of the sky4 ,the sight of the light appeared to animate the engine-men1 for they began to run on faster than before1 the heavy lumbering of the wheels1 and the shouts of1 8,ahead with her60 sounding louder than ever4 ,opposite to where ,rollo and ,jonas were1 there was a light1 tossing and dancing upon the top of a tall pole1 representing the number ten in figures of fire4 8,o ,jonas10 said ,rollo1 8look at that ten40 8,yes10 said ,jonas1 8that is the number of the engine40 8,how can they make such fiery figures80 8,why1 they put the lamp in a glass lantern1 and they paint the glass black1 all except a place left bare1 of the shape of the figure which they wish to have1 and so the light shines through where the glass is not painted1 and that makes the figures of fire40 ,just then ,rollo heard sounds of new uproar and confusion approaching by another street4 ,he looked in the direction1 and saw an engine coming with its long lines of men and its great crowds1 its torches and its thundering sounds4 ,the great mass seemed to be coming on with prodigious momentum4 ,they were coming down into the street where they were1 and ,rollo thought that they would certainly run over ,no4 #aj4 ,when they approached the junction of the streets1 and saw that the street which they were coming into was already filled up with another engine and the crowds about it1 they did not stop1 but kept rushing on1 and swept around the corner directly into the crowd1 where all became mixed and mingled together1 making confusion worse confounded4 ,the crowd became so dense that ,rollo and ,jonas could not have got along at all1 were it not that the crowd itself was moving on2 and so every body that was among them was necessarily borne onwards too4 ,just then ,rollo heard a very loud and hoarse voice calling out1 8,hold on1 ,no4 #aj6 ,hold on1 ,no4 #aj60 8,what's that80 said ,rollo4 8,that's a man with a speaking-trumpet10 said ,jonas4 8,what does he mean by hold on80 8,he means stop10 replied ,jonas4 8,he wants ,no4 #aj engine to stop here40 ,the cry of the engineer1 8,hold on1 ,no4 #aj60 was repeated and reechoed by a great many other voices in the crowd1 though it was mingled and confounded with many other noises1 such as the rumbling of the wheels upon the pavement1 the dinging of the engine bells1 and shouts and outcries from a hundred voices4 ,at last1 however1 the men and boys attached to ,no4 #aj seemed to understand that they were to 8hold on20 and1 accordingly1 the engine gradually came to a stand1 while the other1 which was ,no4 #f1 as ,rollo learned from a bright figure #f which he saw tossing about in the air over the heads of those who were drawing it1 moved on4 ,the men about ,no4 #aj took out some long handles1 which were secured by the side of the engine1 and passed them through some iron rings1 fitted to receive them2 and then they all took hold1 ten or fifteen men on each side ready to work the engine4 ,presently the order was given in the same hoarse and hollow voice from the speaking-trumpet1 8,play away1 ,no4 #aj60 and immediately the men began to work the long handles up and down1 with quick and heavy strokes4 8,why1 ,jonas10 said ,rollo1 8what are they doing80 8,they are working this engine10 said ,jonas4 8,what for80 said ,rollo2 8they are not near the fire40 8,i suppose there is a reservoir near here10 said ,jonas1 8and they are driving the water from it along towards some engine that is near the fire40 8,how does the water go80 said ,rollo4 8,in a hose10 said ,jonas4 8,what is a hose80 asked ,rollo4 8,it is a long leather pipe or tube4 ,come out this way1 and we shall find it1 ,i suppose1 lying along the street40 ,so the boys pushed their way along beyond the engine1 and presently the fire itself burst upon their view in all its glory4 ,it was a store1--one of the stores of a block which extended along the whole street4 ,the front was of brick1 and the walls between the different stores of the block were also of brick1 so that nothing but the inside and the roof could burn4 ,but the whole interior of the building was on fire1 the flames issuing from the windows1 and rising in a great1 bright1 roaring pyramid above the roof1 far up into the dark sky4 ,the whole street1 except exactly opposite to the fire1 where it was too hot for persons to stand1 was filled with men whose faces1 which were all turned towards the fire1 were so brightly illuminated by the light1 that ,rollo could see them more distinctly than if it had been day4 ,from the midst of a dense crowd just beyond the fire1 ,rollo saw a slender white thread of water mounting up in a beautiful curve1 and falling over upon the flames4 ,it was the jet from an engine2 but it seemed to produce no effect upon the flame whatever4 8,there is the hose10 said ,jonas1 suddenly4 ,rollo turned away from the fire to look at the hose which ,jonas pointed out to him1 lying upon the pavement4 ,there were a great many persons coming and going1 so that he could not see very well2 but he perceived a long pipe of leather lying along the street1 in a serpentine direction1 and swelled out with the water which the engine was driving through it1 as if it was just ready to burst4 8,it looks like a snake10 said ,rollo4 8,yes1 and it hisses like a snake too10 replied ,jonas4 ,rollo listened1 and he could just hear a hissing sound mingling with all the other noises4 ,he stepped out into the street to see how the hissing sound was produced4 ,they found that at one of the joints of the hose there was a little leak1 and the water spouted from it in a stream1 which1 though it was very small and slender1 mounted as high as ,rollo's head4 ,the light from the fire shone so brightly upon this part of the street that ,rollo could see the operation very distinctly4 ,jonas thought that it was not very safe for them to remain in the midst of the road much longer2 so they went back to the sidewalk1 and then began to move along towards the fire4 ,the crowd was so dense that they could not get along very well2 but at last they came to a place where they got up upon some steps1 where they could see pretty well1 only that ,rollo was not tall enough4 ,there were many others standing upon the steps1 and ,rollo could not see very well over their shoulders4 ,there was1 however1 a pretty high stone post at the top of the flight of steps1 and very near the house1 where ,jonas thought that perhaps ,rollo could sit1 if he could get him up there4 ,rollo was afraid that the place was not wide enough1 for there was a ball upon the post1 and he could only sit upon that part of the top of the post which was upon one side of the ball4 ,however1 ,rollo was so desirous of seeing them put out the fire1 that he concluded to try1 and so ,jonas helped him climb up4 ,he found the place a better one than he had expected4 ,he clasped one hand around the ball1 and he rested the other upon ,jonas's shoulder and by this means he found that he had a firm and comfortable seat2 and the fire1 with all the operations connected with it1 were in full view before him4 ,just as he got established in his seat1 he saw a stream from another engine beginning to issue from its pipe1 and to rise up towards the building4 ,the man who held the pipe stood upon the top of the engine1 and he held it in such a way as to direct it towards one of the upper windows4 ,rollo could see the red flame through the window1 as the shutter had been burned1 and all the glass had fallen away2 and1 now and then1 a great puff of flame would come out1 when any momentary change in the wind drove the fire in that direction4 ,the stream of water went directly in at the window4 ,at first1 it produced very little effect2 but presently he observed that it began to deaden the redness of the fire just within the window4 ,rollo thought that this engine was far more powerful than the one which he had noticed before4 ,that still continued to play around behind the building4 ,rollo occasionally got a glimpse of other jets1 coming from engines which were standing on that side4 ,sometimes these jets came away over the top of the building1 and ,rollo could see them broken into drops as their force was spent1 but still shooting forward through the flames in regular pulsations1 produced by the successive strokes of the engines from which they came4 ,by all these means1 the fire was soon perceptibly diminished4 ,the window into which the engine was playing soon ceased to look red at all2 and presently ,rollo saw a tall ladder rising slowly above the heads of the crowd4 ,the lower end of it was nearly under the window1 which he had been noticing1 while the other end extended almost across the street1 and slowly rose4 ,rollo was expecting every moment to see it fall back upon the heads of the people who were under it2 but it did not4 ,it ascended slowly and steadily1 until the upper end passed over1 and fell against the building1 a little above the window4 ,in a moment1 a man appeared at the foot1 climbing up the rounds laboriously1 as if he was carrying up a burden which made him mount with difficulty4 ,rollo saw1 pretty soon1 that he had an engine pipe in his hands2 and presently he observed that it was the same man whom he had seen before1 holding the pipe of the engine1 and directing the stream into the window4 ,the man ascended slowly1 dragging up the pipe1 and the hose which was attached to the bottom of it1 until1 at length1 when the hose became so long that he could not lift it any farther1 another man took hold below1 and presently another2 and at last there were four men at different parts of the ladder1 all lifting up the hose4 ,when the man at the top got the pipe up opposite to the window1 he pointed it in1 and then ,rollo could see him looking down1 and gesticulating very violently to those below4 ,he seemed to be calling out to them2 but there was so much noise that ,rollo could not hear what he said4 ,however1 presently the man turned around towards the building again1 and seemed to be attending to his pipe1 and ,rollo could see that the water was spouting through it very furiously into the building4 ,by this time1 the fire had been so much deadened1 by the various jets of water which had been poured upon it from all sides1 that the flames no longer ascended above the roof1 but1 instead of flame1 there was a tall column of dense white smoke1 illuminated by the embers which still glowed below4 ,rollo and ,jonas remained nearly half an hour1 watching the progress of the extinguishing of the fire2 and then1 as ,rollo began to feel his seat somewhat uncomfortable1 they returned together to the hotel4 ,rollo said he wondered that the other buildings did not take fire2 but ,jonas told him that bricks were a pretty good non-conductor of heat1 and that1 if the walls which divided such a block were of proper thickness1 one store was often burned out of the block1 without setting fire to the adjoining buildings4 ,,questions4 ,under what circumstances did ,rollo first hear the alarm of fire8 ,what did he observe in the street when he looked out the window8 ,what is a reservoir8 ,how was the water conveyed from the reservoir to the vicinity of the fire8 ,describe the successive steps of the process by which the fire was extinguished4 ,what did ,jonas say in regard to the reason why the fire was not communicated to the other buildings of the block8 ,,chapter ,,xiii4 ,,the ,,fire ,,in ,,the ,,woods4 ,when ,rollo and ,jonas reached home the next day1 ,rollo gave ,dorothy an account of the conflagration which they had witnessed in the city4 ,dorothy did not appear quite so much interested in his narrative as ,rollo had expected4 ,there are1 in fact1 a great many scenes which it is very interesting to witness1 but which it is very uninteresting to hear described4 ,this is a distinction which a great many travellers1 older and more experienced than ,rollo1 are apt to forget4 ,or rather it is one that they do not understand at all4 ,they attempt to describe to their friends scenes of grandeur or sublimity which impressed their minds very strongly when they witnessed them1 and are surprised to find that they cannot make a similar impression upon others by means of the description4 ,besides1 ,rollo's account was confused and indistinct4 ,it is possible to create a strong impression upon the mind by a description of a storm1 or of a conflagration1 or of any other grand scene4 ,but1 then1 the description must be given skilfully4 ,it must be clear and distinct1 and the several circumstances which contributed most to the production of the general effect1 must be presented fully to the mind1 and in a regular and proper manner4 ,this ,rollo failed to do4 ,he was not experienced in the description of complicated scenes4 ,accordingly1 when he got through with his narrative1 and perceived that ,dorothy did not enter at all into the enthusiasm with which he related it1 he paused a moment1 and then said1-- 8,did you ever see a fire in a great city1 ,dorothy80 8,no10 said ,dorothy4 8,well1 it is a very grand sight1 ,i can assure you10 said ,rollo4 8,i don't believe you ever saw such a grand sight1 in your life40 8,yes1 ,i have10 said ,dorothy4 8,what80 asked ,rollo4 8,a fire in the woods10 replied ,dorothy4 8,o ,dorothy60 said ,rollo2 8a fire in the woods is nothing at all1 compared to a fire in a city4 ,i know1 because ,jonas and ,i have built fires in the woods a hundred times40 8,o1 ,i don't mean your little bonfires10 replied ,dorothy4 8,i mean great fires1 when the woods are burning themselves1 for miles and miles all around40 8,do the woods get on fire like that80 asked ,rollo4 8,yes10 replied ,dorothy4 8,i remember one fire1 in the woods1 when ,i was a little girl1 that came very near burning my father's house4 ,i was quite a little girl40 8,how old80 asked ,rollo4 8,about seven years10 said ,dorothy4 8,it was when my father lived in his log-house in the square opening40 8,what do you mean by that80 asked ,rollo4 8,why1 my father made his cut-down square4 ,there were just five acres40 8,what is a cut-down80 asked ,rollo4 8,the piece where he cut down the trees10 said ,dorothy1 8to make a clearing4 ,first they fall the trees1 and then it is called a cut-down4 ,they let the trees lie all summer1 until they get perfectly dry1 and then they set them on fire1 and burn them4 ,when my father had got his five-acre piece cleared1 he built a log-house upon it1 and there we lived4 ,the opening was full of stumps1 and the woods were all around it1 the stems of the trees standing up thick and close together1 like a wall4 ,we could not see out of the opening any where1 except a little way down the road40 8,and did you live there all alone80 asked ,rollo4 8,o1 no10 said ,dorothy2 8there were my father and mother1 and my brother2 only my father and brother used to be away almost all the time1 at work40 8,well10 said ,rollo1 8tell me about the fire40 8,why1 the first that we knew of it1 was1 that ,i saw one day a great white smoke rolling up over the tops of the trees1 to the north of our house4 ,i asked my mother to come and look at it1 and she did4 ,she said she guessed that ,john ,williams was burning off his piece40 8,who was ,john ,williams80 asked ,rollo4 8,why1 he was one of our neighbors4 ,he lived about two miles off1 and had been falling a piece of woods that spring1 for a crop of wheat4 8,i watched the smoke for some time10 continued ,dorothy1 8and at length it grew smaller and smaller1 and finally ,i could see nothing but a haze4 ,but1 that night1 ,i went out1 about nine o'clock1 to see if my chickens were all safe1--for there were some foxes about at that time1--and ,i saw that the sky looked red in that direction2 so ,i knew that the fire had not all gone out40 8,was that the time10 interrupted ,rollo1 8when you had your hen-coop in a stump80 8,why8 did ,i ever tell you about that80 asked ,dorothy4 8,yes10 replied ,rollo1 8you told me about your hen's laying her eggs in an old hollow stump2 and then your brother made a coop there1 for the chickens40 8,yes10 rejoined ,dorothy1 8that was at the same time4 ,the next morning1 ,i saw the smoke coming up again4 ,it was not so thick as it had been the day before1 when the fire first began to burn2 but it seemed to spread over a larger space40 8,had the fire got into the woods80 asked ,rollo4 8,yes10 replied ,dorothy4 8,my father told us1 when he got home that day to dinner1 that ,john ,williams had let his fire get away from him1 and that it had got into a fine growth of sugar maples1 and was making sad work4 8,my mother asked him if there was not any danger that it would get over to our land2 but my father said no1 not unless the wind should come in strong from the northward4 ,but he said he thought there would be a shower that afternoon1 and that would put it out40 8,and was there a shower80 asked ,rollo4 8,yes10 replied ,dorothy2 8only the cloud brought more wind than rain1 and so it fanned up the fire more than it extinguished it4 ,the rain1 in fact1 only sprinkled the tops of the trees1 leaving all the dry logs1 stumps1 leaves1 and branches1 which lay about upon the ground1 as dry as ever4 ,after the shower1 there was a good fresh breeze all the evening2 and about nine o'clock that evening1 when we went to bed1 the whole sky in that quarter was of a burning red1 as if the heavens were on fire40 8,i should have thought you would have been afraid to go to bed10 said ,rollo4 8,no10 said ,dorothy2 8for the wind went down about nine o'clock1 and1 though the fire looked very bright1 my father said it would not spread any more40 8,how did it look the next morning80 asked ,rollo4 8,it only looked smoky10 replied ,dorothy4 8,in fact1 we never could see any light in the daytime2 nothing but smoke4 ,when there was a wind1 the smoke increased2 and then1 if night came on1 the sky looked bright and glowing2 but if there was not any wind1 the fire seemed to die away4 ,once ,i thought it was all out40 8,and wasn't it80 asked ,rollo4 8,no10 replied ,dorothy2 8my father said that nothing but a good rain would put it out40 8,why did not your father go10 asked ,rollo1 8and put it out with some buckets of water80 8,buckets of water1 child60 said ,dorothy2 8do you suppose that you can put out a fire in the woods with buckets of water80 8,why1 no10 said ,rollo1 8,i suppose not4 ,but they could put it out with such engines as we saw in the city2 ,i know they could40 8,you know a great many things that ,i don't10 said ,dorothy4 8,however1 we did not have any engines1 and so there was nothing to do but to wait for rain4 ,but it happened to be a dry time just then1 and there was not any rain for a week2 and so the fire continued1 sometimes burning up bright1 and sometimes dying away1 but all the time drawing gradually nearer to our house4 8,at last1 one night it got so near that my father said that he did not know but that he ought to sit up and keep watch2 but the wind shifted before bedtime1 and blew it off in another direction1 and so he went to bed4 8,but about midnight ,i heard a great noise1 which waked me up4 ,i opened my eyes1 and looked around1 and ,i saw a great light shining through the cracks40 8,what cracks80 asked ,rollo4 8,why1 the cracks between the slabs40 8,where were the slabs80 asked ,rollo4 8,why1 the upper part of the house was made of slabs1 and there were cracks between them1 where ,i could see out40 8,i should think the wind and rain would come in10 said ,rollo4 8,yes10 replied ,dorothy2 8so they did1 when it was stormy1 but not enough to do any harm1 because ,i could always move my bed away from the side where the wind blew2 only in the winter the snow used to blow away in to my bed1 wherever ,i put it4 ,but that did not do any harm1 because the snow would shake all off again40 8,was not there any window in your chamber80 asked ,rollo4 8,why1 it was not a chamber exactly10 replied ,dorothy2 8we called it a loft4 ,there was a window left in one end1 but that was fastened up by a board4 ,so ,i could only see the lights through the cracks40 8,what was the noise that you heard80 asked ,rollo4 8,it was the noise that my father made calling up my brother1 and running out4 ,then1 besides1 there was a great roaring and crackling of the flames4 ,i got up1 and dressed myself1 and ran down stairs1 and ,i found the woods all on fire close by our house40 8,why1 ,i thought your house was in the middle of the opening10 said ,rollo4 8,no10 replied ,dorothy2 8it was upon one side of the opening1--pretty near the woods4 ,there was a brush fence running along at the edge of the woods1 and a log fence leading from the brush fence to our barnyard4 ,the brush fence was all on fire1 and it was blazing up very high1 and beyond it1 in the woods1 the ground was covered in every direction with heaps of logs1 and branches1 and old trees1 all on fire1 and burning furiously4 ,the air was full of smoke and sparks1 and the wind was driving them directly towards our house and barn4 8,just then ,i heard behind me a great crackling1 which burst out very loud and suddenly4 ,i looked to see what it was1 and ,i found that the fire had got into the top of a great hemlock-tree1 and it was blazing away from the top to the bottom of it4 ,but ,i had no time to stand looking at it1 for my father told me to go and get some water at the spring1 and then to watch1 and look all about the yard1 and if ,i saw the fire catching any where to put it out40 8,why did not he do that himself80 asked ,rollo4 8,o1 he had to go10 replied ,dorothy1 8and pull the log fence to pieces2 for the fire was creeping along the log fence towards our barn4 ,the barn was full of hay1 which my father had got in only a few weeks before1 and there was a great haystack in the barnyard besides2 and if these should get on fire1 the house would probably go too1 for the house was very near40 8,and did they get on fire80 asked ,rollo4 8,no10 replied ,dorothy2 8my father pulled away the log fence1 and then the fire could not get to the house and barn in any way except by sparks through the air4 ,and to keep the sparks from catching on the roof1 he got up upon the barn1 and my brother got upon the house2 and then my mother brought them water from the spring4 ,so they wet the roofs all over4 ,once a spark lighted on the haystack1 and set it on fire2 but my father saw it smoking1 and he came down quick from the barn1 and carried the ladder to the haystack1 and climbed up1 and put it out with his pail of water4 ,there was another spark1 too1 which caught upon the chips in the yard1 near the woodpile2 and ,i put that out40 8,how long did you have to stay80 asked ,rollo4 8,o1 till the morning10 said ,dorothy1 8and then the wind died all away4 ,and in the course of that day1 there came on a rain storm1 and it put the fires out4 ,but when ,i first came out to see it that night1 ,i can tell you the sight was very terrible40 8,yes10 said ,rollo4 8,i think it must have been as terrible as the fire in the city40 8,it was very lonesome too10 said ,dorothy2 8only us four fighting such a great fire40 8,what should you have done10 asked ,rollo1 8if your house had taken fire1 and got burned down80 8,o1 my father would have built us a camp1 and we should have lived in that until he could have time to build us another house4 ,but then ,i don't know what we should have done for hay all the next winter for our oxen and cows4 ,father was much more afraid for the barn than for the house40 8,o ,dorothy60 said ,rollo4 8,why1 there was all the furniture in the house1 and that would have been burned up40 8,no10 replied ,dorothy1 8there was not much furniture2 and what there was we could have got out while the house was burning4 ,the hay was the great thing--the winter's stock of hay40 ,and thus ended ,dorothy's account of the fire in the woods4 ,,questions4 ,to whom did ,rollo attempt to describe the fire which he had witnessed in the city8 ,how did he succeed in the description8 ,what was the difficulty8 ,what scene did ,dorothy attempt to describe to ,rollo8 ,what is a cut-down8 ,in what sort of a place did her father live when the fire in the woods occurred8 ,how did the fire first take8 ,what was its progress the first day8 ,what appearances did it present to ,dorothy8 ,how did they hope that it would be extinguished8 ,describe what took place on the night when the fire reached the clearing4 ---------------------------------------- -------------------------------- ,,transcriber',s ,,notes #a4 ,silently corrected typographical errors and variations in spelling4 #b4 ,archaic1 non-standard1 and uncertain spellings retained as printed4 #c4 ,enclosed italics font in underscores4