,transcriber's note3 ,text enclosed by underscores is in italics 7italics74 ,in view of the difficulty of reliably distinguishing #ahth-century variant spellings from typographical errors1 the text has been reproduced entirely as printed4 99 99 99 99 99 ,,experiments ,,and ,,observations ,,on ,,electricity1 ,,made ,,at ,philadelphia in ,america1 ,,by ,mr4 ,,benjamin ,,franklin1 ,,and ,communicated in several ,letters to ,mr4 ,p4 ,,collinson1 of ,london1 ,f4 ,r4 ,s4 99 99 99 99 99 99 ,,london3 ,printed and sold by ,e4 ,,cave1 at ,st4 ,john's ,gate4 #agea4 7,price #bs4 #f;d47 ,the ,,preface4 ,it may be necessary to acquaint the reader1 that the following observations and experiments were not drawn up with a view to their being made publick1 but were communicated at different times1 and most of them in letters wrote on various topicks1 as matters only of private amusement4 ,but some persons to whom they were read1 and who had themselves been conversant in electrical disquisitions1 were of opinion1 they contain'd so many curious and interesting particulars relative to this affair1 that it would be doing a kind of injustice to the publick1 to confine them solely to the limits of a private acquaintance4 ,the ,editor was therefore prevailed upon to commit such extracts of letters1 and other detach'd pieces as were in his hands to the press1 without waiting for the ingenious author's permission so to do2 and this was done with the less hesitation1 as it was apprehended the author's engagements in other affairs1 would scarce afford him leisure to give the publick his reflections and experiments on the subject1 finish'd with that care and precision1 of which the treatise before us shews he is alike studious and capable4 ,he was only apprized of the step that had been thus taken1 while the first sheets were in the press1 and time enough for him to transmit some farther remarks1 together with a few corrections and additions1 which are placed at the end1 and may be consulted in the perusal4 ,the experiments which our author relates are most of them peculiar to himself2 they are conducted with judgment1 and the inferences from them plain and conclusive2 though sometimes proposed under the terms of suppositions and conjectures4 ,and indeed the scene he opens1 strikes us with a pleasing astonishment1 whilst he conducts us by a train of facts and judicious reflections1 to a probable cause of those phnomena1 which are at once the most awful1 and1 hitherto1 accounted for with the least verisimilitude4 ,he exhibits to our consideration1 an invisible1 subtile matter1 disseminated through all nature in various proportions1 equally unobserved1 and1 whilst all those bodies to which it peculiarly adheres are alike charged with it1 inoffensive4 ,he shews1 however1 that if an unequal distribution is by any means brought about2 if there is a coacervation in one part of space1 a less proportion1 vacuity1 or want1 in another2 by the near approach of a body capable of conducting the coacervated part to the emptier space1 it becomes perhaps the most formidable and irresistible agent in the universe4 ,animals are in an ,instant struck breathless1 bodies almost impervious by any force yet known1 are perforated1 and metals fused by it1 in a moment4 ,from the similar effects of lightening and electricity our author has been led to make some propable conjectures on the cause of the former2 and at the same time1 to propose some rational experiments in order to secure ourselves1 and those things on which its force is often directed1 from its pernicious effects2 a circumstance of no small importance to the publick1 and therefore worthy of the utmost attention4 ,it has1 indeed1 been of late the fashion to ascribe every grand or unusual operation of nature1 such as lightening and earthquakes1 to electricity2 not1 as one would imagine1 from the manner of reasoning on these occasions1 that the authors of these schemes have1 discovered any connection betwixt the cause and effect1 or saw in what manner they were related2 but1 as it would seem1 merely because they were unacquainted with any other agent1 of which it could not positively be said the connection was impossible4 ,but of these1 and many other interesting circumstances1 the reader will be more satisfactorily informed in the following letters1 to which he is therefore referred by ,the ,,editor4 ,illustration ,,letter ,i4 ,,from ,mr ,,benj4 ,,franklin1 in ,philadelphia4 ,,to ,mr ,,peter ,,collinson1 ,f4,r4,s4 ,london4 ,july #bh1 #agdg4 ,,sir1 ,,the necessary trouble of copying long letters1 which perhaps when they come to your hands may contain nothing new1 or worth your reading 7so quick is the progress made with you in ,electricity7 half discourages me from writing any more on that subject4 ,yet ,i cannot forbear adding a few observations on ,m4 ,muschenbroek's wonderful bottle4 #a4 ,the non-electric contain'd in the bottle differs when electrised from a non-electric electrised out of the bottle1 in this3 that the electrical fire of the latter is accumulated on its surface1 and forms an electrical atmosphere round it of considerable extent3 but the electrical fire is crouded into the substance of the former1 the glass confining it4 #b4 ,at the same time that the wire and top of the bottle1 c4 is electrised positively or plus1 the bottom of the bottle is electrised negatively or minus1 in exact proportion3 i4 e4 whatever quantity of electrical fire is thrown in at top1 an equal quantity goes out of the bottom4 ,to understand this1 suppose the common quantity of ,electricity in each part of the bottle1 before the operation begins1 is equal to #bj2 and at every stroke of the tube1 suppose a quantity equal to #a is thrown in2 then1 after the first stroke1 the quantity contain'd in the wire and upper part of the bottle will be #ba1 in the bottom #ai4 ,after the second1 the upper part will have #bb1 the lower #ah1 and so on 'till after #bj strokes1 the upper part will have a quantity of electrical fire equal to #dj1 the lower part none3 and then the operation ends3 for no more can be thrown into the upper part1 when no more can be driven out of the lower part4 ,if you attempt to throw more in1 it is spued back thro' the wire1 or flies out in loud cracks thro' the sides of the bottle4 #c4 ,the equilibrium cannot be restored in the bottle by inward communication or contact of the parts2 but it must be done by a communication formed without the bottle1 between the top and bottom1 by some non-electric1 touching both at the same time2 in which case it is restored with a violence and quickness inexpressible3 or1 touching each alternately1 in which case the equilibrium is restored by degrees4 #d4 ,as no more electrical fire can be thrown into the top of the bottle1 when all is driven out of the bottom1 so in a bottle not yet electrised1 none can be thrown into the top1 when none can get out at the bottom2 which happens either when the bottom is too thick1 or when the bottle is placed on an electric per se4 ,again1 when the bottle is electrised1 but little of the electrical fire can be drawn out from the top1 by touching the wire1 unless an equal quantity can at the same time get in at the bottom4 ,thus1 place an electrised bottle on clean glass or dry wax1 and you will not1 by touching the wire1 get out the fire from the top4 ,place it on a non-electric1 and touch the wire1 you will get it out in a short time2 but soonest when you form a direct communication as above4 ,so wonderfully are these two states of ,electricity1 the plus and minus1 combined and balanced in this miraculous bottle6 situated and related to each other in a manner that ,i can by no means comprehend6 ,if it were possible that a bottle should in one part contain a quantity of air strongly comprest1 and in another part a perfect vacuum1 we know the equilibrium would be instantly restored within4 ,but here we have a bottle containing at the same time a plenum of electrical fire1 and a vacuum of the same fire2 and yet the equilibrium cannot be restored between them but by a communication without6 though the plenum presses violently to expand1 and the hungry vacuum seems to attract as violently in order to be filled4 #e4 ,the shock to the nerves 7or convulsion rather7 is occasion'd by the sudden passing of the fire through the body in its way from the top to the bottom of the bottle4 ,the fire takes the shortest course1 as ,mr ,watson justly observes3 ,but it does not appear1 from experiment1 that1 in order for a person to be shocked1 a communication with the floor is necessary2 for he that holds the bottle with one hand1 and touches the wire with the other1 will be shock'd as much1 though his shoes be dry1 or even standing on wax1 as otherwise4 ,and on the touch of the wire 7or of the gun-barrel1 which is the same thing7 the fire does not proceed from the touching finger to the wire1 as is supposed1 but from the wire to the finger1 and passes through the body to the other hand1 and so into the bottom of the bottle4 ,,experiments confirming the above4 ,,experiment ,i4 ,place an electrised phial on wax2 a small cork-ball suspended by a dry silk-thread held in your hand1 and brought near to the wire1 will first be attracted1 and then repelled3 when in this state of repellency1 sink your hand1 that the ball may be brought towards the bottom of the bottle2 it will there be instantly and strongly attracted1 'till it has parted with its fire4 ,if the bottle had an electrical atmosphere1 as well as the wire1 an electrified cork would be repelled from one as well as from the other4 ,,experiment ,,ii4 ,,fig4 #a4 ,from a bent wire 7a7 sticking in the table1 let a small linen thread 7b7 hang down within half an inch of the electrised phial 7c74 ,touch the wire of the phial repeatedly with your finger1 and at every touch you will see the thread instantly attracted by the bottle4 7,this is best done by a vinegar cruet1 or some such belly'd bottle74 ,as soon as you draw any fire out from the upper part by touching the wire1 the lower part of the bottle draws an equal quantity in by the thread4 ,,experiment ,,iii4 ,,fig4 #b4 ,fix a wire in the lead1 with which the bottom of the bottle is armed1 7d7 so as that bending upwards1 its ring-end may be level with the top or ring-end of the wire in the cork 7e71 and at three or four inches distance4 ,then electricise the bottle1 and place it on wax4 ,if a cork suspended by a silk thread 7f7 hang between these two wires1 it will play incessantly from one to the other1 'till the bottle is no longer electrised2 that is1 it fetches and carries fire from the top to the bottom of the bottle1 'till the equilibrium is restored4 ,,experiment ,,iv4 ,,fig4 #c4 ,place an electricised phial on wax2 take a wire 7g7 in form of a ,c1 the ends at such a distance when bent1 as that the upper may touch the wire of the bottle1 when the lower touches the bottom3 stick the outer part on a stick of sealing wax 7h7 which will serve as a handle4 ,then apply the lower end to the bottom of the bottle1 and gradually bring the upper-end near the wire in the cork4 ,the consequence is1 spark follows spark till the equilibrium is restored4 ,touch the top first1 and on approaching the bottom with the other end1 you have a constant stream of fire1 from the wire entering the bottle4 ,touch the top and bottom together1 and the equilibrium will soon be restored1 but silently and imperceptibly2 the crooked wire forming the communication4 ,,experiment ,v4 ,,fig4 #d4 ,let a ring of thin lead or paper surround a bottle 7i71 even at some distance from or above the bottom4 ,from that ring let a wire proceed up1 'till it touch the wire of the cork 7k74 ,a bottle so fixt cannot by any means be electrised3 the equilibrium is never destroyed3 for while the communication between the upper and lower parts of the bottle is continued by the outside wire1 the fire only circulates3 what is driven out at bottom1 is constantly supply'd from the top4 ,hence a bottle cannot be electrised that is foul or moist on the outside4 ,,experiment ,,vi4 ,place a man on a cake of wax1 and present him the wire of the electrified phial to touch1 you standing on the floor1 and holding it in your hand4 ,as often as he touches it1 he will be electrified plus2 and any one standing on the floor may draw a spark from him4 ,the fire in this experiment passes out of the wire into him2 and at the same time out of your hand into the bottom of the bottle4 ,,experiment ,,vii4 ,give him the electrified phial to hold2 and do you touch the wire2 as often you touch it he will be electrified minus1 and may draw a spark from any one standing on the floor4 ,the fire now passes from the wire to you1 and from him into the bottom of the bottle4 ,,experiment ,,viii4 ,lay two books on two glasses1 back towards back1 two or three ,inches distant4 ,set the electrified phial on one1 and then touch the wire2 that book will be electrified minus2 the electrical fire being drawn out of it by the bottom of the bottle4 ,take off the bottle1 and holding it in your hand1 touch the other with the wire2 that book will be electrised plus2 the fire passing into it from the wire1 and the bottle at the same time supply'd from your hand4 ,a suspended small cork-ball will play between these books 'till the equilibrium is restored4 ,,experiment ,,ix4 ,when a body is electrised plus it will repel an electrified feather or small cork-ball4 ,when minus 7or when in the common state7 it will attract them1 but stronger when minus than when in the common state1 the difference being greater4 ,,experiment ,x4 ,tho'1 as in ,,exper4 ,,vi4 a man standing on wax may be electrised a number of times1 by repeatedly touching the wire of an electrised bottle 7held in the hand of one standing on the floor7 he receiving the fire from the wire each time3 yet holding it in his own hand1 and touching the wire1 tho' he draws a strong spark1 and is violently shock'd1 no ,electricity remains in him2 the fire only passing thro' him from the upper to the lower part of the bottle4 ,observe1 before the shock1 to let some one on the floor touch him to restore the equilibrium in his body2 for in taking hold of the bottom of the bottle1 he sometimes becomes a little electrised minus1 which will continue after the shock2 as would also any plus ,electricity1 which he might have given him before the shock4 ,for1 restoring the equilibrium in the bottle does not at all affect the ,electricity in the man thro' whom the fire passes2 that ,electricity is neither increased nor diminish'd4 ,,experiment ,,xi4 ,the passing of the electrical fire from the upper to the lower part of the bottle1 to restore the equilibrium is render'd strongly visible by the following pretty experiment4 ,take a book whose cover is filletted with gold2 bend a wire of eight or ten inches long in the form of 7m7 ,,fig4 #e1 slip it on the end of the cover of the book over the gold line1 so as that the shoulder of it may press upon one end of the gold line1 the ring up1 but leaning towards the other end of the book4 ,lay the book on a glass or wax2 and on the other end of the gold lines1 set the bottle electrised3 then bend the springing wire1 by pressing it with a stick of wax till its ring approaches the ring of the bottle wire2 instantly there is a strong spark and stroke1 and the whole line of gold1 which completes the communication between the top and bottom of the bottle1 will appear a vivid flame1 like the sharpest lightning4 ,the closer the contact between the shoulder of the wire1 and the gold at one end of the line1 and between the bottom of the bottle and the gold at the other end1 the better the experiment succeeds4 ,the room should be darkened4 ,if you would have the whole filletting round the cover appear in fire at once1 let the bottle and wire touch the gold in the diagonally opposite corners4 ,i am1 c4 ,b4 ,,franklin4 ,,letter ,,ii4 ,,from ,mr ,,benj4 ,,franklin1 in ,philadelphia4 ,,to ,mr ,,peter ,,collinson1 ,f4,r4,s4 ,london4 ,sept4 #a1 #agdg4 ,,sir1 ,in my last ,i informed you that1 in pursuing our electrical enquiries1 we had observed some particular ,phnomena1 which we looked upon to be new1 and of which ,i promised to give you some account1 tho' ,i apprehended they might possibly not be new to you1 as so many hands are daily employ'd in electrical experiments on your side the water1 some or other of which would probably hit on the same observations4 ,the first is the wonderful effect of pointed bodies1 both in drawing off and throwing off the electrical fire4 ,for example3 ,place an iron shot of three or four inches diameter1 on the mouth of a clean dry glass bottle4 ,by a fine silken thread from the cieling1 right over the mouth of the bottle1 suspend a small cork-ball1 about the bigness of a marble2 the thread of such a length1 as that the cork-ball may rest against the side of the shot4 ,electrify the shot1 and the ball will be repelled to the distance of four or five inches1 more or less1 according to the quantity of ,electricity4--,when in this state1 if you present to the shot the point of a long slender sharp bodkin1 at six or eight inches distance1 the repellency is instantly destroy'd1 and the cork flies to the shot4 ,a blunt body must be brought within an inch1 and draw a spark1 to produce the same effect4 ,to prove that the electrical fire is drawn off by the point1 if you take the blade of the bodkin out of the wooden handle1 and fix it in a stick of sealing wax1 and then present it at the distance aforesaid1 or if you bring it very near1 no such effect follows2 but sliding one finger along the wax till you touch the blade1 and the ball flies to the shot immediately4--,if you present the point in the dark1 you will see1 sometimes at a foot distance1 and more1 a light gather upon it like that of a fire-fly or glow-worm2 the less sharp the point1 the nearer you must bring it to observe the light2 and at whatever distance you see the light1 you may draw off the electrical fire1 and destroy the repellency4--,if a cork-ball so suspended be repelled by the tube1 and a point be presented quick to it1 tho' at a considerable distance1 'tis surprizing to see how suddenly it flies back to the tube4 ,points of wood will do as well as those of iron1 provided the wood is not dry2 for perfectly dry wood will no more conduct ,electricity than sealing wax4 ,to shew that points will throw off as well as draw off the electrical fire2 lay a long sharp needle upon the shot1 and you cannot electrise the shot1 so as to make it repel the cork-ball4--,or fix a needle to the end of a suspended gun-barrel1 or iron rod1 so as to point beyond it like a little bayonet2 and while it remains there1 the gun-barrel1 or rod1 cannot by applying the tube to the other end be electrised so as to give a spark1 the fire continually running out silently at the point4 ,in the dark you may see it make the same appearance as it does in the case beforementioned4 ,the repellency between the cork-ball and the shot is likewise destroy'd2 #a4 ,by sifting fine sand on it2 this does it gradually4 #b4 ,by breathing on it4 #c4 ,by making a smoke about it from burning wood4#a #d4 ,by candle light1 even tho' the candle is at a foot distance3 these do it suddenly4--,the light of a bright coal from a wood fire2 and the light of red-hot iron do it likewise2 but not at so great a distance4 ,smoke from dry rosin dropt on hot iron1 does not destroy the repellency2 but is attracted by both shot and cork-ball1 forming proportionable atmospheres round them1 making them look beautifully1 somewhat like some of the figures in ,burnet's or ,whiston's theory of the earth4 ,n4 ,b4 ,this experiment should be made in a closet where the air is very still4 ,the light of the sun thrown strongly on both cork and shot by a looking-glass for a long time together1 does not impair the repellency in the least4 ,this difference between fire-light and sun-light1 is another thing that seems new and extraordinary to us4 ,we had for some time been of opinion1 that the electrical fire was not created by friction1 but collected1 being really an element diffus'd among1 and attracted by other matter1 particularly by water and metals4 ,we had even discovered and demonstrated its afflux to the electrical sphere1 as well as its efflux1 by means of little light windmill wheels made of stiff paper vanes1 fixed obliquely and turning freely on fine wire axes4 ,also by little wheels of the same matter1 but formed like water wheels4 ,of the disposition and application of which wheels1 and the various phnomena resulting1 ,i could1 if ,i had time1 fill you a sheet4 ,the impossibility of electrising one's self 7tho' standing on wax7 by rubbing the tube and drawing the fire from it2 and the manner of doing it by passing the tube near a person or thing standing on the floor1 c4 had also occurred to us some months before ,mr ,watson's ingenious ,sequel came to hand1 and these were some of the new things ,i intended to have communicated to you4--,but now ,i need only mention some particulars not hinted in that piece1 with our reasonings thereupon2 though perhaps the latter might well enough be spared4 #a4 ,a person standing on wax1 and rubbing the tube1 and another person on wax drawing the fire2 they will both of them1 7provided they do not stand so as to touch one another7 appear to be electrised1 to a person standing on the floor2 that is1 he will perceive a spark on approaching each of them with his knuckle4 #b4 ,but if the persons on wax touch one another during the exciting of the tube1 neither of them will appear to be electrised4 #c4 ,if they touch one another after exciting the tube1 and drawing the fire as aforesaid1 there will be a stronger spark between them1 than was between either of them and the person on the floor4 #d4 ,after such strong spark1 neither of them discover any electricity4 ,these appearances we attempt to account for thus4 ,we suppose as aforesaid1 that electrical fire is a common element1 of which every one of the three persons abovementioned has his equal share1 before any operation is begun with the ,tube4 ,a1 who stands on wax and rubs the tube collects the electrical fire from himself into the glass2 and his communication with the common stock being cut off by the wax1 his body is not again immediately supply'd4 ,b1 7who stands on wax likewise7 passing his knuckle along near the tube1 receives the fire which was collected by the glass from ,a2 and his communication with the common stock being likewise cut off1 he retains the additional quantity received4--,to ,c1 standing on the floor1 both appear to be electrised3 for he having only the middle quantity of electrical fire1 receives a spark upon approaching ,b1 who has an over quantity2 but gives one to ,a1 who has an under quantity4 ,if ,a and ,b approach to touch each other1 the spark is stronger1 because the difference between them is greater2 after such touch there is no spark between either of them and ,c1 because the electrical fire in all is reduced to the original equality4 ,if they touch while electrising1 the equality is never destroy'd1 the fire only circulating4 ,hence have arisen some new terms among us3 we say1 ,b1 7and bodies like circumstanced7 is electrised positively2 ,a1 negatively4 ,or rather1 ,b is electrised plus2 ,a1 minus4 ,and we daily in our experiments electrise bodies plus or minus as we think proper4--,to electrise plus or minus1 no more needs to be known than this1 that the parts of the tube or sphere that are rubbed1 do1 in the instant of the friction attract the electrical fire1 and therefore take it from the thing rubbing3 the same parts immediately1 as the friction upon them ceases1 are disposed to give the fire they have received1 to any body that has less4 ,thus you may circulate it1 as ,mr ,watson has shewn2 you may also accumulate or substract it upon or from any body1 as you connect that body with the rubber or with the receiver1 the communication with the common stock being cut off4 ,we think that ingenious gentleman was deceived1 when he imagined 7in his ,sequel7 that the electrical fire came down the wire from the cieling to the gun-barrel1 thence to the sphere1 and so electrised the machine and the man turning the wheel1 c4 ,we suppose it was driven off1 and not brought on thro' that wire2 and that the machine and man1 c4 were electrised minus2 i4 e4 had less electrical fire in them than things in common4 ,as the vessel is just upon sailing1 ,i cannot give you so large an account of ,american ,electricity as ,i intended3 ,i shall only mention a few particulars more4--,we find granulated lead better to fill the phial with1 than water1 being easily warmed1 and keeping warm and dry in damp air4--,we fire spirits with the wire of the phial4--,we light candles1 just blown out1 by drawing a spark among the smoke between the wire and snuffers4--,we represent lightning1 by passing the wire in the dark over a china plate that has gilt flowers1 or applying it to gilt frames of looking-glasses1 c4--,we electrise a person twenty or more times running1 with a touch of the finger on the wire1 thus3 ,he stands on wax4 ,give him the electrised bottle in his hand4 ,touch the wire with your finger1 and then touch his hand or face2 there are sparks every time4--,we encrease the force of the electrical kiss vastly1 thus3 ,let ,a and ,b stand on wax2 give one of them the electrised phial in hand2 let the other take hold of the wire2 there will be a small spark2 but when their lips approach1 they will be struck and shock'd4 ,the same if another gentleman and lady1 ,c and ,d1 standing also on wax1 and joining hands with ,a and ,b1 salute1 or shake hands4--,we suspend by fine silk thread a counterfeit spider1 made of a small piece of burnt cork1 with legs of linnen thread1 and a grain or two of lead stuck in him to give him more weight4 ,upon the table1 over which he hangs1 we stick a wire upright as high as the phial and wire1 two or three inches from the spider2 then we animate him by setting the electrified phial at the same distance on the other side of him2 he will immediately fly to the wire of the phial1 bend his legs in touching it1 then spring off1 and fly to the wire in the table2 thence again to the wire of the phial1 playing with his legs against both in a very entertaining manner1 appearing perfectly alive to persons unacquainted4 ,he will continue this motion an hour or more in dry weather4--,we electrify1 upon wax in the dark1 a book that has a double line of gold round upon the covers1 and then apply a knuckle to the gilding2 the fire appears every where upon the gold like a flash of lightning3 not upon the leather1 nor1 if you touch the leather instead of the gold4 ,we rub our tubes with buckskin1 and observe always to keep the same side to the tube1 and never to sully the tube by handling2 thus they work readily and easily1 without the least fatigue2 especially if kept in tight pastboard cases1 lined with flannel1 and fitting closeto the tube4#b--,this ,i mention because the ,european papers1 on ,electricity1 frequently speak of rubbing the tube1 as a fatiguing exercise4 ,our spheres are fixed on iron axes1 which pass through them4 ,at one end of the axis there is a small handle1 with which we turn the sphere like a common grindstone4 ,this we find very commodious1 as the machine takes up but little room1 is portable1 and may be enclosed in a tight box1 when not in use4 ',tis true1 the sphere does not turn so swift1 as when the great wheel is used3 but swiftness we think of little importance1 since a few turns will charge the phial1 c4 sufficiently4 ,i am1 c4 ,b4 ,,franklin4 ,illustration ,,letter ,,iii4 ,,from ,mr ,,benj4 ,,franklin1 in ,philadelphia4 ,,to ,mr ,,peter ,,collinson1 ,f4,r4,s4 ,london4 ,farther ,,experiments and ,,observations in ,,electricity4 #agdh4 ,,sir1 #a4 ,there will be the same explosion and shock1 if the electrified phial is held in one hand by the hook1 and the coating touch'd with the other1 as when held by the coating1 and touch'd at the hook4 #b4 ,to take the charg'd phial safely by the hook1 and not at the same time diminish its force1 it must first be set down on an electric per se4 #c4 ,the phial will be electrified as strongly1 if held by the hook1 and the coating apply'd to the globe or tube2 as when held by the coating1 and the hook apply'd4 #d4 ,but the direction of the electrical fire being different in the charging1 will also be different in the explosion4 ,the bottle charged thro' the hook1 will be discharged thro' the hook2 the bottle charged thro' the coating1 will be discharged thro' the coating1 and not other ways3 for the fire must come out the same way it went in4 #e4 ,to prove this2 take two bottles that were equally charged thro' the hooks1 one in each hand2 bring their hooks near each other1 and no spark or shock will follow2 because each hook is disposed to give fire1 and neither to receive it4 ,set one of the bottles down on glass1 take it up by the hook1 and apply its coating to the hook of the other2 then there will be an explosion and shock1 and both bottles will be discharged4 #f4 ,vary the experiment1 by charging two phials equally1 one thro' the hook1 the other thro' the coating3 hold that by the coating which was charged thro' the hook2 and that by the hook which was charg'd thro' the coating3 apply the hook of the first to the coating of the other1 and there will be no shock or spark4 ,set that down on glass which you held by the hook1 take it up by the coating1 and bring the two hooks together3 a spark and shock will follow1 and both phials be discharged4 ,in this experiment the bottles are totally discharged1 or the equilibrium within them restored4 ,the abounding of fire in one of the hooks 7or rather in the internal surface of one bottle7 being exactly equal to the wanting of the other3 and therefore1 as each bottle has in itself the abounding as well as the wanting1 the wanting and abounding must be equal in each bottle4 ,see 4 #h1 #i1 #aj1 #aa4 ,but if a man holds in his hands two bottles1 one fully electrify'd1 the other not at all1 and brings their hooks together1 he has but half a shock1 and the bottles will both remain half electrified1 the one being half discharged1 and the other half charged4 #g4 ,place two phials equally charged on a table at five or six inches distance4 ,let a cork-ball1 suspended by a silk thread1 hang between them4 ,if the phials were both charged through their hooks1 the cork1 when it has been attracted and repell'd by the one1 will not be attracted1 but equally repelled by the other4 ,but if the phials were charged1 the one through the hook1 and the other#c through the coating1 the ball1 when it is repelled from one hook1 will be as strongly attracted by the other1 and play vigorously between them1 'till both phials are nearly discharged4 #h4 ,when we use the terms of charging and discharging the phial1 'tis in compliance with custom1 and for want of others more suitable4 ,since we are of opinion1 that there is really no more electrical fire in the phial after what is called its charging1 than before1 nor less after its discharging2 excepting only the small spark that might be given to1 and taken from1 the non-electric matter1 if separated from the bottle1 which spark may not be equal to a five hundredth part of what is called the explosion4 ,for if1 on the explosion1 the electrical fire came out of the bottle by one part1 and did not enter in again by another2 then1 if a man standing on wax1 and holding the bottle in one hand1 takes the spark by touching the wire hook with the other1 the bottle being thereby discharged1 the man would be charged2 or whatever fire was lost by one1 would be found in the other1 since there is no way for its escape3 ,but the contrary is true4 #i4 ,besides the phial will not suffer what is called a charging1 unless as much fire can go out of it one way1 as is thrown in by another4 ,a phial cannot be charged standing on wax or glass1 or hanging on the prime conductor1 unless a communication be form'd between its coating and the floor4 #aj4 ,but suspend two or more phials on the prime conductor1 one hanging to the tail of the other2 and a wire from the last to the floor1 an equal number of turns of the wheel shall charge them all equally1 and every one as much as one alone would have been4 ,what is driven out at the tail of the first1 serving to charge the second2 what is driven out of the second charging the third2 and so on4 ,by this means a great number of bottles might be charged with the same labour1 and equally high1 with one alone1 were it not that every bottle receives new fire1 and loses its old with some reluctance1 or rather gives some small resistance to the charging1 which in a number of bottles becomes more equal to the charging power1 and so repels the fire back again on the globe1 sooner than a single bottle would do4 #aa4 ,when a bottle is charged in the common way1 its inside and outside surfaces stand ready1 the one to give fire by the hook1 the other to receive it by the coating2 the one is full1 and ready to throw out1 the other empty and extremely hungry2 yet as the first will not give out1 unless the other can at the same instant receive in2 so neither will the latter receive in1 unless the first can at the same instant give out4 ,when both can be done at once1 'tis done with inconceivable quickness and violence4 #ab4 ,so a strait spring 7tho' the comparison does not agree in every particular7 when forcibly bent1 must1 to restore itself1 contract that side which in the bending was extended1 and extend that which was contracted2 if either of these two operations be hindered1 the other cannot be done4 ,but the spring is not said to be charg'd with elasticity when bent1 and discharg'd when unbent2 its quantity of elasticity is always the same4 #ac4 ,glass1 in like manner1 has1 within its substance1 always the same quantity of electrical fire1 and that a very great quantity in proportion to the mass of glass1 as shall be shewn hereafter4 #ad4 ,this quantity1 proportioned to the glass1 it strongly and obstinately retains1 and will have neither more nor less1 though it will suffer a change to be made in its parts and situation2 i4 e4 we may take away part of it from one of the sides1 provided we throw an equal quantity into the other4 #ae4 ,yet when the situation of the electrical fire is thus altered in the glass2 when some has been taken from one side1 and some added to the other1 it will not be at rest or in its natural state1 till 'tis restored to its original equality4--,and this restitution cannot be made through the substance of the glass1 but must be done by a non-electric communication formed without1 from surface to surface4 #af4 ,thus1 the whole force of the bottle1 and power of giving a shock1 is in the ,,glass ,,itself2 the non-electrics in contact with the two surfaces1 serving only to give and receive to and from the several parts of the glass2 that is1 to give on one side1 and take away from the other4 #ag4 ,this was discovered here in the following manner4 ,purposing to analyse the electrified bottle1 in order to find wherein its strength lay1 we placed it on glass1 and drew out the cork and wire which for that purpose had been loosely put in4 ,then taking the bottle in one hand1 and bringing a finger of the other near its mouth1 a strong spark came from the water1 and the shock was as violent as if the wire had remained in it1 which shewed that the force did not lie in the wire4 ,then to find if it resided in the water1 being crouded into and condensed in it1 as connfi'd by the glass1 which had been our former opinion1 we electrify'd the bottle again1 and placing it on glass1 drew out the wire and cork as before2 then taking up the bottle we decanted all its water into an empty bottle1 which likewise stood on glass2 and taking up that other bottle1 we expected if the force resided in the water1 to find a shock from it2 but there was none4 ,we judged then1 that it must either be lost in decanting1 or remain in the first bottle4 ,the latter we found to be true3 for that bottle on trial gave the shock1 though filled up as it stood with fresh unelectrified water from a tea-pot4--,to find then1 whether glass had this property merely as glass1 or whether the form contributed any thing to it2 we took a pane of sash-glass1 and laying it on the stand1 placed a plate of lead on its upper surface2 then electrify'd that plate1 and bringing a finger to it1 there was a spark and shock4 ,we then took two plates of lead of equal dimensions1 but less than the glass by two inches every way1 and electrified the glass between them1 by electrifying the uppermost lead2 then separated the glass from the lead1 in doing which1 what little fire might be in the lead was taken out and the glass being touched in the electrified parts with a finger1 afforded only very small pricking sparks1 but a great number of them might be taken from different places4 ,then dexterously placing it again between the leaden plates1 and compleating a circle between the two surfaces1 a violent shock ensued4--,which demonstrated the power to reside in glass as glass1 and that the non-electrics in contact served only1 like the armature of a loadstone1 to unite the force of the several parts1 and bring them at once to any point desired3 it being a property of a non-electric1 that the whole body instantly receives or gives what electrical fire is given to or taken from any one of its parts4 #ah4 ,upon this1 we made what we call'd an electrical-battery1 consisting of eleven panes of large sash-glass1 arm'd with thin leaden plates pasted on each side1 placed vertically1 and supported at two inches distance on silk cords1 with thick hooks of leaden wire1 one from each side1 standing upright1 distant from each other1 and convenient communications of wire and chain1 from the giving side of one pane1 to the receiving side of the other2 that so the whole might be charged together1 and with the same labour as one single pane2 and another contrivance to bring the giving sides1 after charging1 in contact with one long wire1 and the receivers with another1 which two long wires would give the force of all the plates of glass at once through the body of any animal forming the circle with them4 ,the plates may also be discharged separately1 or any number together that is required4 ,but this machine is not much used1 as not perfectly answering our intention with regard to the ease of charging1 for the reason given #aj4 ,we made also of large glass panes1 magical pictures1 and self-moving animated wheels1 presently to be described4 #ai4 ,i perceive by the ingenious ,mr ,watson's last book1 lately received1 that ,dr ,bevis had used1 before we had1 panes of glass to give a shock2 though1 till that book came to hand1 ,i thought to have communicated it to you as a novelty4 ,the excuse for mentioning it here1 is1 that we tried the experiment differently1 drew different consequences from it1 7for ,mr ,watson still seems to think the fire accumulated on the non-electric that is in contact with the glass1 page #gb7 and1 as far as we hitherto know1 have carried it farther4 #bj4 ,the magical picture is made thus4 ,having a large metzotinto with a frame and glass1 suppose of the ,,king1 7,god preserve him7 take out the print1 and cut a pannel out of it1 near two inches distant from the frame all round4 ,if the cut is through the picture 'tis not the worse4 ,with thin paste or gum-water1 fix the border that is cut off on the inside of the glass1 pressing it smooth and close2 then fill up the vacancy by gilding the glass well with leaf gold or brass4 ,gild likewise the inner edge of the back of the frame all round except the top part1 and form a communication between that gilding and the gilding behind the glass3 then put in the board1 and that side is finished4 ,turn up the glass1 and gild the fore side exactly over the back gilding1 and when it is dry1 cover it by pasting on the pannel of the picture that had been cut out1 observing to bring the corresponding parts of the border and picture together1 by which the picture will appear of a piece as at first1 only part is behind the glass1 and part before4--,hold the picture horizontally by the top1 and place a little moveable gilt crown on the king's-head4 ,if now the picture be moderately electrified1 and another person take hold of the frame with one hand1 so that his fingers touch its inside gilding1 and with the other hand endeavour to take off the crown1 he will receive a terrible blow1 and fail in the attempt4 ,if the picture were highly charged1 the consequence might perhaps be as fatal as that of high-treason2 for when the spark is taken through a quire of paper laid on the picture1 by means of a wire communication1 it makes a fair hole through every sheet1 that is1 through #dh leaves1 7though a quire of paper is thought good armour against the push of a sword or even against a pistol bullet7 and the crack is exceeding loud4 ,the operator1 who holds the picture by the upper-end1 where the inside of the frame is not gilt1 to prevent its falling1 feels nothing of the shock1 and may touch the face of the picture without danger1 which he pretends is a test of his loyalty4--,if a ring of persons take the shock among them1 the experiment is called1 ,the ,conspirators4 #ba4 ,on the principle1 in #g1 that hooks of bottles1 differently charged1 will attract and repel differently1 is made1 an electrical wheel1 that turns with considerable strength4 ,a small upright shaft of wood passes at right angles through a thin round board1 of about twelve inches diameter1 and turns on a sharp point of iron fixed in the lower end1 while a strong wire in the upper-end passing thro' a small hole in a thin brass plate1 keeps the shaft truly vertical4 ,about thirty radii of equal length1 made of sash glass cut in narrow strips1 issue horizontally from the circumference of the board1 the ends most distant from the center being about four inches apart4 ,on the end of every one1 a brass thimble is fixed4 ,if now the wire of a bottle electrified in the common way1 be brought near the circumference of this wheel1 it will attract the nearest thimble1 and so put the wheel in motion2 that thimble1 in passing by1 receives a spark1 and thereby being electrified is repelled and so driven forwards2 while a second being attracted1 approaches the wire1 receives a spark1 and is driven after the first1 and so on till the wheel has gone once round1 when the thimbles before electrified approaching the wire1 instead of being attracted as they were at first1 are repelled1 and the motion presently ceases4--,but if another bottle which had been charged through the coating be placed near the same wheel1 its wire will attract the thimble repelled by the first1 and thereby double the force that carries the wheel round2 and not only taking out the fire that had been communicated to the thimbles by the first bottle1 but even robbing them of their natural quantity1 instead of being repelled when they come again towards the first bottle1 they are more strongly attracted1 so that the wheel mends its pace1 till it goes with great rapidity twelve or fifteen rounds in a minute1 and with such strength1 as that the weight of one hundred ,spanish dollars with which we once loaded it1 did not seem in the least to retard its motion4--,this is called an electrical jack2 and if a large fowl were spitted on the upright shaft1 it would be carried round before a fire with a motion fit for roasting4 #bb4 ,but this wheel1 like those driven by wind1 water1 or weights1 moves by a foreign force1 to wit1 that of the bottles4 ,the self-moving wheel1 though constructed on the same principles1 appears more surprising4 ',tis made of a thin round plate of window-glass1 seventeen inches diameter1 well gilt on both sides1 all but two inches next the edge4 ,two small hemispheres of wood are then fixed with cement to the middle of the upper and under sides1 centrally opposite1 and in each of them a thick strong wire eight or ten inches long1 which together make the axis of the wheel4 ,it turns horizontally on a point at the lower end of its ,axis1 which rests on a bit of brass cemented within a glass salt-celler4 ,the upper end of its axis passes thro' a hole in a thin brass plate cemented to a long strong piece of glass1 which keeps it six or eight inches distant from any non-electric1 and has a small ball of wax or metal on its top to keep in the fire4 ,in a circle on the table which supports the wheel1 are fixed twelve small pillars of glass1 at about four inches distance1 with a thimble on the top of each4 ,on the edge of the wheel is a small leaden bullet communicating by a wire with the gilding of the upper surface of the wheel2 and about six inches from it is another bullet communicating in like manner with the under surface4 ,when the wheel is to be charged by the upper surface1 a communication must be made from the under surface to the table4 ,when it is well charg'd it begins to move2 the bullet nearest to a pillar moves towards the thimble on that pillar1 and passing by electrifies it and then pushes itself from it2 the succeeding bullet1 which communicates with the other surface of the glass1 more strongly attracts that thimble on account of its being before electrified by the other bullet2 and thus the wheel encreases its motion till it comes to such a height as that the resistance of the air regulates it4 ,it will go half an hour1 and make one minute with another twenty turns in a minute1 which is six hundred turns in the whole2 the bullet of the upper surface giving in each turn twelve sparks1 to the thimbles1 which make seven thousand two hundred sparks2 and the bullet of the under surface receiving as many from the thimbles2 those bullets moving in the time near two thousand five hundred feet4--,the thimbles are well fixed1 and in so exact a circle1 that the bullets may pass within a very small distance of each of them4--,if instead of two bullets you put eight1 four communicating with the upper surface1 and four with the under surface1 placed alternately2 which eight1 at about six inches distance1 compleats the circumference1 the force and swiftness will be greatly increased1 the wheel making fifty turns in a minute2 but then it will not continue moving so long4--,these wheels may be applied1 perhaps1 to the ringing of chimes1 and moving of light-made ,orreries4 #bc4 ,a small wire bent circularly with a loop at each end2 let one end rest against the under surface of the wheel1 and bring the other end near the upper surface1 it will give a terrible crack1 and the force will be discharged4 #bd4 ,every spark in that manner drawn from the surface of the wheel1 makes a round hole in the gilding1 tearing off a part of it in coming out2 which shews that the fire is not accumulated on the gilding1 but is in the glass itself4 #be4 ,the gilding being varnish'd over with turpentine varnish1 the varnish tho' dry and hard1 is burnt by the spark drawn thro' it1 and gives a strong smell and visible smoke4 ,and when the spark is drawn through paper1 all round the hole made by it1 the paper will be blacked by the smoke1 which sometimes penetrates several of the leaves4 ,part of the gilding torn off1 is also found forcibly driven into the hole made in the paper by the stroke4 #bf4 ',tis amazing to observe in how small a portion of glass a great electrical force may lie4 ,a thin glass bubble1 about an inch diameter1 weighing only six grains1 being half-filled with water1 partly gilt on the outside1 and furnish'd with a wire hook1 gives1 when electrified1 as great a shock as a man can well bear4 ,as the glass is thickest near the orifice1 ,i suppose the lower half1 which being gilt was electrified1 and gave the shock1 did not exceed two grains2 for it appeared1 when broke1 much thinner than the upper half4--,if one of these thin bottles be electrified by the coating1 and the spark taken out thro' the gilding1 it will break the glass inwards at the same time that it breaks the gilding outwards4 #bg4 ,and allowing 7for the reasons before given1 #h1 #i1 #aj17 that there is no more electrical fire in a bottle after charging1 than before1 how great must be the quantity in this small portion of glass6 ,it seems as if it were of its very substance and essence4 ,perhaps if that due quantity of electrical fire so obstinately retained by glass1 could be separated from it1 it would no longer be glass2 it might lose its transparency1 or its brittleness1 or its elasticity4--,experiments may possibly be invented hereafter1 to discover this4 #bg4 ,we are surprized at the account given in ,mr ,watson's book1 of a shock communicated through a great space of dry ground1 and suspect there must be some metaline quality in the gravel of that ground2 having found that simple dry earth1 rammed in a glass tube1 open at both ends1 and a wire hook inserted in the earth at each end1 the earth and wires making part of a circle1 would not conduct the least perceptible shock1 and indeed when one wire was electrify'd1 the other hardly showed any signs of its being in connection with it4--,even a thoroughly wet pack-thread sometimes fails of conducting a shock1 tho' it otherwise conducts electricity very well4 ,a dry cake of ice1 or an icicle held between two in a circle1 likewise prevents the shock2 which one would not expect1 as water conducts it so perfectly well4--,gilding on a new book1 though at first it conducts the shock extremely well1 yet fails after ten or a dozen experiments1 though it appears otherwise in all respects the same1 which we cannot account for4 #bh4 ,there is one experiment more which surprizes us1 and is not hitherto satisfactorily accounted for2 it is this4 ,place an iron shot on a glass stand1 and let a ball of damp cork1 suspended by a silk thread1 hang in contact with the shot4 ,take a bottle in each hand1 one that is electrify'd through the hook1 the other through the coating3 ,apply the giving wire to the shot1 which will electrify it positively1 and the cork shall be repelled3 ,then apply the requiring wire1 which will take out the spark given by the other2 when the cork will return to the shot3 ,apply the same again1 and take out another spark1 so will the shot be electrify'd negatively2 and the cork in that case shall be repelled equally as before4 ,then apply the giving wire to the shot1 and give the spark it wanted1 so will the cork return3 ,give it another1 which will be an addition to its natural quantity1 so will the cork be repelled again3 ,and so may the experiment be repeated as long as there is any charge in the bottles4 ,which shews that bodies having less than the common quantity of ,electricity1 repel each other1 as well as those that have more4 ,chagrined a little that we have hitherto been able to produce nothing in this way of use to mankind2 and the hot weather coming on1 when electrical experiments are not so agreeable1 'tis proposed to put an end to them for this season1 somewhat humorously1 in a party of pleasure1 on the banks of ,skuylkill4#d ,spirits1 at the same time1 are to be fired by a spark sent from side to side through the river1 without any other conductor than the water2 an experiment which we some time since performed1 to the amazement of many4 ,a turkey is to be killed for our dinner by the electrical shock1 and roasted by the electrical jack1 before a fire kindled by the electrified bottle2 when the healths of all the famous electricians in ,england1 ,holland1 ,france1 and ,germany1 are to be drank in #e;electrified bumpers1 under the discharge of guns from the electrical battery4 ,april #bi1 #agdi4 ,illustration ,,letter ,,iv4 ,,containing ,,observations and ,,suppositions1 towards forming a new ,,hypothesis1 for explaining the several ,phnomena of ,,thunder-,,gusts4#f ,,sir1 4 #a4 ,non-electric bodies1 that have electric fire thrown into them1 will retain it 'till other non-electrics1 that have less1 approach2 and then 'tis communicated by a snap1 and becomes equally divided4 #b4 ,electrical fire loves water1 is strongly attracted by it1 and they can subsist together4 #c4 ,air is an electric per se1 and when dry will not conduct the electrical fire2 it will neither receive it1 nor give it to other bodies2 otherwise no body surrounded by air could be electrified positively and negatively3 for should it be attempted positively1 the air would immediately take away the overplus2 or negatively1 the air would supply what was wanting4 #d4 ,water being electrified1 the vapours arising from it will be equally electrified2 and floating in the air1 in the form of clouds1 or otherwise1 will retain that quantity of electrical fire1 till they meet with other clouds or bodies not so much electrified1 and then will communicate as beforementioned4 #e4 ,every particle of matter electrified is repelled by every other particle equally electrified4 ,thus the stream of a fountain1 naturally dense and continual1 when electrified1 will separate and spread in the form of a brush1 every drop endeavouring to recede from every other drop4 ,but on taking out the electrical fire1 they close again4 #f4 ,water being strongly electrified 7as well as when heated by common fire7 rises in vapours more copiously2 the attraction of cohesion among its particles being greatly weakened1 by the opposite power of repulsion introduced with the electrical fire2 and when any particle is by any means disengaged1 'tis immediately repelled1 and so flies into the air4 #g4 ,particles happening to be situated as ,a and ,b1 are more easily disengaged than ,c and ,d1 as each is held by contact with three only1 whereas ,c and ,d are each in contact with nine4 ,when the surface of water has the least motion1 particles are continually pushed into the situation represented by ,,fig4 #f4 #h4 ,friction between a non-electric and an electric per se1 will produce electrical fire2 not by creating1 but collecting it3 for it is equally diffused in our walls1 floors1 earth1 and the whole mass of common matter4 ,thus the whirling glass globe1 during its friction against the cushion1 draws fire from the cushion1 the cushion is supplied from the frame of the machine1 that from the floor on which it stands4 ,cut off the communication by thick glass or wax placed under the cushion1 and no fire can be produced1 because it cannot be collected4 #i4 ,the ,ocean is a compound of water1 a non-electric1 and salt an electric per se4 #aj4 ,when there is a friction among the parts near its surface1 the electrical fire is collected from the parts below4 ,it is then plainly visible in the night2 it appears at the stern and in the wake of every sailing vessel2 every dash of an oar shows it1 and every surff and spray3 in storms the whole sea seems on fire4--,the detach'd particles of water then repelled from the electrified surface1 continually carry off the fire as it is collected2 they rise1 and form clouds1 and those clouds are highly electrified1 and retain the fire 'till they have an opportunity of communicating it4 #aa4 ,the particles of water rising in vapours1 attach themselves to particles of air4 #ab4 ,the particles of air are said to be hard1 round1 separate and distant from each other2 every particle strongly repelling every other particle1 whereby they recede from each other1 as far as common gravity will permit4 #ac4 ,the space between any three particles equally repelling each other1 will be an equilateral triangle4 #ad4 ,in air compressed1 these triangles are smaller2 in rarified ,air they are larger4 #ae4 ,common fire joined with air1 increases the repulsion1 enlarges the triangles1 and thereby makes the air specifically lighter4 ,such ,air among denser air1 will rise4 #af4 ,common fire1 as well as electrical fire gives repulsion to the particles of water1 and destroys their attraction of cohesion2 hence common fire1 as well as electrical fire1 assists in raising vapours4 #ag4 ,particles of water1 having no fire in them1 mutually attract each other4 ,three particles of water then being attached to the three particles of a triangle of air1 would by their mutual attraction operating against the air's repulsion1 shorten the sides and lessen the triangle1 whereby that portion of air being made denser1 would sink to the earth with its water1 and not rise to contribute to the formation of a cloud4 #ah4 ,but if every particle of water attaching itself to air1 brings with it a particle of common fire1 the repulsion of the air being assisted and strengthened by the fire1 more than obstructed by the mutual attraction of the particles of water1 the triangle dilates1 and that portion of air becoming rarer and specifically lighter rises4 #ai4 ,if the particles of water bring electrical fire when they attach themselves to air1 the repulsion between the particles of water electrified1 joins with the natural repulsion of the air1 to force its particles to a greater distance1 whereby the triangles are dilated1 and the air rises1 carrying up with it the water4 #bj4 ,if the particles of water bring with them portions of both sorts of fire1 the repulsions of the particles of air is still more strengthened and increased1 and the triangles farther enlarged4 #ba4 ,one particle of air may be surrounded by twelve particles of water of equal size with itself1 all in contact with it2 and by more added to those4 #bb4 ,particles of air thus loaded would be drawn nearer together by the mutual attraction of the particles of water1 did not the fire1 common or electrical1 assist their repulsion4 #bc4 ,if air thus loaded be compressed by adverse winds1 or by being driven against mountains1 c4 or condensed by taking away the fire that assisted it in expanding2 the triangles contract1 the air with its water will descend as a dew2 or1 if the water surrounding one particle of air comes in contact with the water surrounding another1 they coalesce and form a drop1 and we have rain4 #bd4 ,the sun supplies 7or seems to supply7 common fire to all vapours1 whether raised from earth or sea4 #be4 ,those vapours which have both common and electrical fire in them1 are better supported1 than those which have only common fire in them4 ,for when vapours rise into the coldest region above the earth1 the cold will not diminish the electrical fire1 if it doth the common4 #bf4 ,hence clouds formed by vapours raised from fresh waters within land1 from growing vegetables1 moist earth1 c4 more speedily and easily deposite their water1 having but little electrical fire to repel and keep the particles separate4 ,so that the greatest part of the water raised from the land is let fall on the land again2 and winds blowing from the land to the sea are dry2 there being little use for rain on the sea1 and to rob the land of its moisture1 in order to rain on the sea1 would not appear reasonable4 #bg4 ,but clouds formed by vapours raised from the sea1 having both fires1 and particularly a great quantity of the electrical1 support their water strongly1 raise it high1 and being moved by winds may bring it over the middle of the broadest continent from the middle of the widest ocean4 #bh4 ,how these ocean clouds1 so strongly supporting their water1 are made to deposite it on the land where 'tis wanted1 is next to be considered4 #bi4 ,if they are driven by winds against mountains1 those mountains being less electrified attract them1 and on contact take away their electrical fire 7and being cold1 the common fire also27 hence the particles close towards the mountains and towards each other4 ,if the air was not much loaded1 it only falls in dews on the mountain tops and sides1 forms springs1 and descends to the vales in rivulets1 which united make larger streams and rivers4 ,if much loaded1 the electrical fire is at once taken from the whole cloud2 and1 in leaving it1 flashes brightly and cracks loudly2 the particles instantly coalescing for want of that fire1 and falling in a heavy shower4 #cj4 ,when a ridge of mountains thus dams the clouds1 and draws the electrical fire from the cloud first approaching it2 that which next follows1 when it comes near the first cloud1 now deprived of its fire1 flashes into it1 and begins to deposite its own water2 the first cloud again flashing into the mountains2 the third approaching cloud1 and all the succeeding ones1 acting in the same manner as far back as they extend1 which may be over many hundred miles of country4 #ca4 ,hence the continual storms of rain1 thunder1 and lightning on the east-side of the ,andes1 which running north and south1 and being vastly high1 intercept all the clouds brought against them from the ,atlantic ocean by the trade winds1 and oblige them to deposite their waters1 by which the vast rivers ,amazons1 ,la ,plata1 and ,oroonoko are formed1 which return the water into the same sea1 after having fertilized a country of very great extent4 #cb4 ,if a country be plain1 having no mountains to intercept the electrified clouds1 yet is it not without means to make them deposite their water4 ,for if an electrified cloud coming from the sea1 meets in the air a cloud raised from the land1 and therefore not electrified2 the first will flash its fire into the latter1 and thereby both clouds shall be made suddenly to deposite water4 #cc4 ,the electrified particles of the first cloud close when they lose their fire2 the particles of the other cloud close in receiving it3 in both1 they have thereby an opportunity of coalescing into drops4--,the concussion or jerk given to the air1 contributes also to shake down the water1 not only from those two clouds but from others near them4 ,hence the sudden fall of rain immediately after flashes of lightning4 #cd4 ,to shew this by an easy experiment4 ,take two round pieces of pasteboard two inches diameter2 from the center and circumference of each of them suspend by fine silk threads eighteen inches long1 seven small balls of wood1 or seven peas equal in bigness2 so will the balls appending to each pasteboard1 form equal equilateral triangles1 one ball being in the center1 and six at equal distances from that1 and from each other2 and thus they represent particles of air4 ,dip both sets in water1 and some cohering to each ball they will represent air loaded4 ,dexterously electrify one set1 and its balls will repel each other to a greater distance1 enlarging the triangles4 ,could the water supported by the seven balls come into contact1 it would form a drop or drops so heavy as to break the cohesion it had with the balls1 and so fall4--,let the two sets then represent two clouds1 the one a sea cloud electrified1 the other a land cloud4 ,bring them within the sphere of attraction1 and they will draw towards each other1 and you will see the separated balls close thus2 the first electrified ball that comes near an unelectrified ball by attraction joins it1 and gives it fire2 instantly they separate1 and each flies to another ball of its own party1 one to give1 the other to receive fire2 and so it proceeds through both sets1 but so quick as to be in a manner instantaneous4 ,in the collision they shake off and drop their water1 which represents rain4 #ce4 ,thus when sea and land clouds would pass at too great a distance for the flash1 they are attracted towards each other till within that distance2 for the sphere of electrical attraction is far beyond the distance of flashing4 #cf4 ,when a great number of clouds from the sea meet a number of clouds raised from the land1 the electrical flashes appear to strike in different parts2 and as the clouds are jostled and mixed by the winds1 or brought near by the electrical attraction1 they continue to give and receive flash after flash1 till the electrical fire is equally diffused4 #cg4 ,when the gun-barrel 7in electrical experiments7 has but little electrical fire in it1 you must approach it very near with your knuckle1 before you can draw a spark4 ,give it more fire1 and it will give a spark at a greater distance4 ,two gun-barrels united1 and as highly electrified1 will give a spark at a still greater distance4 ,but if two gun-barrels electrified will strike at two inches distance1 and make a loud snap1 to what a great distance may #aj1jjj acres of electrified cloud strike and give its fire1 and how loud must be that crack6 #ch4 ,it is a common thing to see clouds at different heights passing different ways1 which shews different currents of air1 one under the other4 ,as the air between the tropics is rarified by the sun1 it rises1 the denser northern and southern air pressing into its place4 ,the air so rarified and forced up1 passes northward and southward1 and must descend in the polar regions1 if it has no opportunity before1 that the circulation may be carried on4 #ci4 ,as currents of air1 with the clouds therein1 pass different ways1 'tis easy to conceive how the clouds1 passing over each other1 may attract each other1 and so come near enough for the electrical stroke4 ,and also how electrical clouds may be carried within land very far from the sea1 before they have an opportunity to strike4 #dj4 ,when the air1 with its vapours raised from the ocean between the tropics1 comes to descend in the polar regions1 and to be in contact with the vapours arising there1 the electrical fire they brought begins to be communicated1 and is seen in clear nights1 being first visible where 'tis first in motion1 that is1 where the contact begins1 or in the most northern part2 from thence the streams of light seem to shoot southerly1 even up to the zenith of northern countries4 ,but tho' the light seems to shoot from the north southerly1 the progress of the fire is really from the south northerly1 its motion beginning in the north being the reason that 'tis there first seen4 ,for the electrical fire is never visible but when in motion1 and leaping from body to body1 or from particle to particle thro' the air4 ,when it passes thro' dense bodies 'tis unseen4 ,when a wire makes part of the circle1 in the explosion of the electrical phial1 the fire1 though in great quantity1 passes in the wire invisibly3 but in passing along a chain1 it becomes visible as it leaps from link to link4 ,in passing along leaf-gilding 'tis visible3 for the leaf-gold is full of pores2 hold a leaf to the light and it appears like a net2 and the fire is seen in its leaping over the vacancies4--,and as when a long canal filled with still water is opened at one end1 in order to be discharged1 the motion of the water begins first near the opened end1 and proceeds towards the close end1 tho' the water itself moves from the close towards the opened end3 so the electrical fire discharged into the polar regions1 perhaps from a thousand leagues length of vaporiz'd air1 appears first where 'tis first in motion1 i4 e4 in the most northern part1 and the appearance proceeds southward1 tho' the fire really moves northward4 ,this is supposed to account for the ,aurora ,borealis4 #da4 ,when there is great heat on the land1 in a particular region 7the sun having shone on it perhaps several days1 while the surrounding countries have been screen'd by clouds7 the lower air is rarified and rises1 the cooler denser air above descends2 the clouds in that air meet from all sides1 and join over the heated place2 and if some are electrified1 others not1 lightning and thunder succeed1 and showers fall4 ,hence thunder-gusts after heats1 and cool air after gusts2 the water and the clouds that bring it1 coming from a higher and therefore a cooler region4 #db4 ,an electrical spark1 drawn from an irregular body at some distance is scarce ever strait1 but shows crooked and waving in the air4 ,so do the flashes of lightning2 the clouds being very irregular bodies4 #dc4 ,as electrified clouds pass over a country1 high hills and high trees1 lofty towers1 spires1 masts of ships1 chimneys1 c4 as so many prominencies and points1 draw the electrical fire1 and the whole cloud discharges there4 #dd4 ,dangerous1 therefore1 is it to take shelter under a tree during a thunder-gust4 ,it has been fatal to many1 both men and beasts4 #de4 ,it is safer to be in the open field for another reason4 ,when the clothes are wet1 if a flash in its way to the ground should strike your head1 it will run in the water over the surface of your body2 whereas1 if your clothes were dry1 it would go thro' the body4 ,hence a wet rat cannot be killed by the exploding electrical bottle1 when a dry rat may4 #df4 ,common fire is in all bodies1 more or less1 as well as electrical fire4 ,perhaps they may be different modifications of the same element2 or they may be different elements4 ,the latter is by some suspected4 #dg4 ,if they are different things1 yet they may and do subsist together in the same body4 #dh4 ,when electrical fire strikes thro' a body1 it acts upon the common fire contained in it1 and puts that fire in motion2 and if there be a sufficient quantity of each kind of fire1 the body will be inflamed4 #di4 ,when the quantity of common fire in the body is small1 the quantity of the electrical fire 7or the electrical stroke7 should be greater3 if the quantity of common fire be great1 less electrical fire suffices to produce the effect4 #ej4 ,thus spirits must be heated before we can fire them by the electrical spark4 ,if they are much heated a small spark will do2 if not1 the spark must be greater4 #ea4 ,till lately we could only fire warm vapours2 but now we can burn hard dry rosin4 ,and when we can procure greater electrical sparks1 we may be able to fire not only unwarm'd spirits1 as lightning does1 but even wood1 by giving sufficient agitation to the common fire contained in it1 as friction we know will do4 #eb4 ,sulphureous and inflammable vapours arising from the earth1 are easily kindled by lightning4 ,besides what arise from the earth1 such vapours are sent out by stacks of moist hay1 corn1 or other vegetables1 which heat and reek4 ,wood rotting in old trees or buildings does the same4 ,such are therefore easily and often fired4 #ec4 ,metals are often melted by lightning1 tho' perhaps not from heat in the lightning1 nor altogether from agitated fire in the metals4--,for as whatever body can insinuate itself between the particles of metal1 and overcome the attraction by which they cohere 7as sundry menstrua can7 will make the solid become a fluid1 as well as fire1 yet without heating it3 so the electrical fire1 or lightning1 creating a violent repulsion between the particles of the metal it passes thro'1 the metal is fused4 #ed4 ,if you would1 by a violent fire1 melt off the end of a nail1 which is half driven into a door1 the heat given the whole nail before a part would melt1 must burn the board it sticks in4 ,and the melted part would burn the floor it dropp'd on4 ,but if a sword can be melted in the scabbard1 and money in a man's pocket1 by lightning1 without burning either1 it must be a cold fusion4 #ee4 ,lightning rends some bodies4 ,the electrical spark will strike a hole thro' a quire of strong paper4 #ef4 ,if the source of lightning1 assigned in this paper1 be the true one1 there should be little thunder heard at sea far from land4 ,and accordingly some old sea-captains1 of whom enquiry has been made1 do affirm1 that the fact agrees perfectly with the hypothesis2 for that1 in crossing the great ocean1 they seldom meet with thunder till they come into soundings2 and that the islands far from the continent have very little of it4 ,and a curious observer1 who lived #ac years at ,bermudas1 says1 there was less thunder there in that whole time than he has sometimes heard in a month at ,carolina4 ,,additional ,,papers4 ,,to ,mr4 ,,peter ,,collinson1 ,f4,r4,s4 ,london4 ,,philadelphia1 ,july #bi1 #agej ,,sir1 ,as you first put us on electrical experiments1 by sending to our library company a tube1 with directions how to use it2 and as our honourable proprietary enabled us to carry those experiments to a greater height1 by his generous present of a compleat electrical apparatus2 'tis fit that both should know from time to time what progress we make4 ,it was in this view ,i wrote and sent you my former papers on this subject1 desiring1 that as ,i had not the honour of a direct correspondence with that bountiful benefactor to our library1 they might be communicated to him through your hands4 ,in the same view ,i write1 and send you this additional paper4 ,if it happens to bring you nothing new 7which may well be1 considering the number of ingenious men in ,europe1 continually engaged in the same researches7 at least it will show1 that the instruments1 put into our hands1 are not neglected2 and1 that if no valuable discoveries are made by us1 whatever the cause may be1 it is not want of industry and application4 ,i am1 ,sir1 ,your much obliged ,humble ,servant1 ,b4 ,,franklin4 ,,opinions and ,,conjectures1 ,concerning the ,properties and ,effects of the electrical ,matter1 arising from ,experiments and ,observations1 made in ,philadelphia1 #agdi4 #a4 ,the electrical matter consists of particles extreamly subtile1 since it can permeate common matter1 even the densest metals1 with such ease and freedom1 as not to receive any perceptible resistance4 #b4 ,if any one should doubt1 whether the electrical matter passes thro' the substance of bodies1 or only over and along their surfaces1 a shock from an electrified large glass jar1 taken thro' his own body1 will probably convince him4 #c4 ,electrical matter differs from common matter in this1 that the parts of the latter mutually attract1 those of the former mutually repel1 each other4 ,hence the appearing divergency in a stream of electrified effluvia4 #d4 ,but tho' the particles of electrical matter do repel each other1 they are strongly attracted by all other matter4#g #e4 ,from these three things1 the extreme subtilty of the electrical matter1 the mutual repulsion of its parts1 and the strong attraction between them and other matter1 arise this effect1 that when a quantity of electrical matter1 is applied to a mass of common matter1 of any bigness or length within our observation 7which has not already got its quantity7 it is immediately and equally diffused through the whole4 #f4 ,thus common matter is a kind of spunge to the electrical fluid4 ,and as a spunge would receive no water1 if the parts of water were not smaller than the pores of the spunge2 and even then but slowly1 if there were not a mutual attraction between those parts and the parts of the spunge2 and would still imbibe it faster1 if the mutual attraction among the parts of the water did not impede1 some force being required to separate them2 and fastest1 if1 instead of attraction1 there were a mutual repulsion among those parts1 which would act in conjunction with the attraction of the spunge4 ,so is the case between the electrical and common matter4 #g4 ,but in common matter there is 7generally7 as much of the electrical1 as it will contain within its substance4 ,if more is added1 it lies without upon the surface1 and forms what we call an electrical atmosphere3 and then the body is said to be electrified4 #h4 ',tis supposed1 that all kinds of common matter do not attract and retain the electrical1 with equal strength and force2 for reasons to be given hereafter4 ,and that those called electrics per se1 as glass1 c4 attract and retain it strongest1 and contain the greatest quantity4 #i4 ,we know that the electrical fluid is in common matter1 because we can pump it out by the globe or tube4 ,we know that common matter has near as much as it can contain1 because1 when we add a little more to any protion of it1 the additional quantity does not enter1 but forms an electrical atmosphere4 ,and we know that common matter has not 7generally7 more than it can contain1 otherwise all loose portions of it would repel each other1 as they constantly do when they have electric atmospheres4 #aj4 ,the beneficial uses of this electrical fluid in the creation1 we are not yet well acquainted with1 though doubtless such there are1 and those very considerable2 but we may see some pernicious consequences1 that would attend a much greater proportion of it4 ,for had this globe we live on as much of it in proportion1 as we can give to a globe of iron1 wood1 or the like1 the particles of dust and other light matters that get loose from it1 would1 by virtue of their separate electrical atmospheres1 not only repel each other1 but be repelled from the earth1 and not easily be brought to unite with it again2 whence our air would continually be more and more clogged with foreign matter1 and grow unfit for respiration4 ,this affords another occasion of adoring that wisdom which has made all things by weight and measure6 #aa4 ,if a piece of common matter be supposed intirely free from electrical matter1 and a single particle of the latter be brought nigh1 'twill be attracted and enter the body1 and take place in the center1 or where the attraction is every way equal4 ,if more particles enter1 they take their places where the balance is equal between the attraction of the common matter and their own mutual repulsion4 ',tis supposed they form triangles1 whose sides shorten as their number increases2 'till the common matter has drawn in so many1 that its whole power of compressing those triangles by attraction1 is equal to their whole power of expanding themselves by repulsion2 and then will such piece of matter receive no more4 #ab4 ,when part of this natural proportion of electrical fluid1 is taken out of a piece of common matter1 the triangles formed by the remainder1 are supposed to widen by the mutual repulsion of the parts1 until they occupy the whole piece4 #ac4 ,when the quantity of electrical fluid taken from a piece of common matter is restored again1 it enters1 the expanded triangles being again compressed till there is room for the whole4 #ad4 ,to explain this3 take two apples1 or two balls of wood or other matter1 each having its own natural quantity of the electrical fluid4 ,suspend them by silk lines from the ceiling4 ,apply the wire of a well-charged vial1 held in your hand1 to one of them 7,a7 ,fig4 #g4 and it will receive from the wire a quantity of the electrical fluid2 but will not imbibe it1 being already full4 ,the fluid therefore will flow round its surface1 and form an electrical atmosphere4 ,bring ,a into contact with ,b1 and half the electrical fluid is communicated1 so that each has now an electrical atmosphere1 and therefore they repel each other4 ,take away these atmospheres by touching the balls1 and leave them in their natural state3 then1 having fixed a stick of sealing wax to the middle of the vial to hold it by1 apply the wire to ,a1 at the same time the coating touches ,b4 ,thus will a quantity of the electrical fluid be drawn out of ,b1 and thrown on ,a4 ,so that ,a will have a redundance of this fluid1 which forms an atmosphere round it1 and ,b an exactly equal deficiency4 ,now bring these balls again into contact1 and the electrical atmosphere will not be divided between ,a and ,b1 into two smaller atmospheres as before2 for ,b will drink up the whole atmosphere of ,a1 and both will be found again in their natural state4 #ae4 ,the form of the electrical atmosphere is that of the body it surrounds4 ,this shape may be rendered visible in a still air1 by raising a smoke from dry rosin1 dropt into a hot tea-spoon under the electrised body1 which will be attracted and spread itself equaly on all sides1 covering and concealing the body4 ,and this form it takes1 because it is attracted by all parts of the surface of the body1 tho' it cannot enter the substance already replete4 ,without this attraction it would not remain round the body1 but dissipate in the air4 #af4 ,the atmosphere of electrical particles surrounding an electrified sphere1 is not more disposed to leave it or more easily drawn off from any one part of the sphere than from another1 because it is equally attracted by every part4 ,but that is not the case with bodies of any other figure4 ,from a cube it is more easily drawn at the corners than at the plane sides1 and so from the angles of a body of any other form1 and still most easily from the angle that is most acute4 ,thus if a body shaped as ,a1 ,b1 ,c1 ,d1 ,e1 in ,fig4 #h1 be electrified1 or have an electrical atmosphere communicated to it1 and we consider every side as a base on which the particles rest and by which they are attracted1 one may see1 by imagining a line from ,a to ,f1 and another from ,e to ,g1 that the portion of the atmosphere included in ,f1 ,a1 ,e1 ,g1 has the line ,a1 ,e1 for its basis4 ,so the portion of atmosphere included in ,h1 ,a1 ,b1 ,i1 has the line ,a1 ,b1 for its basis4 ,and likewise the portion included in ,k1 ,b1 ,c1 ,l1 has ,b1 ,c1 to rest on2 and so on the other side of the figure4 ,now if you would draw off this atmosphere with any blunt smooth body1 and approach the middle of the side ,a1 ,b1 you must come very near before the force of your attracter exceeds the force or power with which that side holds its atmosphere4 ,but there is a small portion between ,i1 ,b1 ,k1 that has less of the surface to rest on1 and to be attracted by1 than the neighbouring portions1 while at the same time there is a mutual repulsion between its particles and the particles of those portions1 therefore here you can get it with more ease or at a greater distance4 ,between ,f1 ,a1 ,h1 there is a larger portion that has yet a less surface to rest on and to attract it2 here therefore you can get it away still more easily4 ,but easiest of all between ,l1 ,c1 ,m1 where the quantity is largest1 and the surface to attract and keep it back the least4 ,when you have drawn away one of these angular portions of the fluid1 another succeeds in its place1 from the nature of fluidity and the mutual repulsion beforementioned2 and so the atmosphere continues flowing off at such angle1 like a stream1 till no more is remaining4 ,the extremities of the portions of atmosphere over these angular parts are likewise at a greater distance from the electrified body1 as may be seen by the inspection of the above figure2 the point of the atmosphere of the angle ,c1 being much farther from ,c1 than any other part of the atmosphere over the lines ,c1 ,b1 or ,b1 ,a3 ,and besides the distance arising from the nature of the figure1 where the attraction is less1 the particles will naturally expand to a greater distance by their mutual repulsion4 ,on these accounts we suppose electrified bodies discharge their atmospheres upon unelectrified bodies more easily and at a greater distance from their angles and points than from their smooth sides4--,those points will also discharge into the air1 when the body has too great an electrical atmosphere1 without bringing any non-electric near1 to receive what is thrown off3 ,for the air1 though an electric per se1 yet has always more or less water and other non-electric matters mixed with it2 and these attract and receive what is so discharged4 #ag4 ,but points have a property1 by which they draw on as well as throw off the electrical fluid1 at greater distances than blunt bodies can4 ,that is1 as the pointed part of an electrified body will discharge the atmosphere of that body1 or communicate it farthest to another body1 so the point of an unelectrified body1 will draw off the electrical atmosphere from an electrified body1 farther than a blunter part of the same unelectrified body will do4 ,thus a pin held by the head1 and the point presented to an electrified body1 will draw off its atmosphere at a foot distance2 where if the head were presented instead of the point1 no such effect would follow4 ,to understand this1 we may consider1 that if a person standing on the floor would draw off the electrical atmosphere from an electrified body1 an iron crow and a blunt knitting kneedle held alternately in his hand and presented for that purpose1 do not draw with different forces in proportion to their different masses4 ,for the man1 and what he holds in his hand1 be it large or small1 are connected with the common mass of unelectrified matter2 and the force with which he draws is the same in both cases1 it consisting in the different proportion of electricity in the electrified body and that common mass4 ,but the force with which the electrified body retains its atmosphere by attracting it1 is proportioned to the surface over which the particles are placed2 i4e4 four square inches of that surface retain their atmosphere with four times the force that one square inch retains its atmosphere4 ,and as in plucking the hairs from the horse's tail1 a degree of strength insufficient to pull away a handful at once1 could yet easily strip it hair by hair2 so a blunt body presented cannot draw off a number of particles at once1 but a pointed one1 with no greater force1 takes them away easily1 particle by particle4 #ah4 ,these explanations of the power and operation of points1 when they first occurr'd to me1 and while they first floated in my mind1 appeared perfectly satisfactory2 but now ,i have wrote them1 and consider'd them more closely in black and white1 ,i must own ,i have some doubts about them3 yet as ,i have at present nothing better to offer in their stead1 ,i do not cross them out3 for even a bad solution read1 and its faults discover'd1 has often given rise to a good one in the mind of an ingenious reader4 #ai4 ,nor is it of much importance to us1 to know the manner in which nature executes her laws2 'tis enough if we know the laws themselves4 ',tis of real use to know1 that china left in the air unsupported will fall and break2 but how it comes to fall1 and why it breaks1 are matters of speculation4 ',tis a pleasure indeed to know them1 but we can preserve our china without it4 #bj4 ,thus in the present case1 to know this power of points1 may possibly be of some use to mankind1 though we should never be able to explain it4 ,the following experiments1 as well as those in my first paper1 show this power4 ,i have a large prime conductor made of several thin sheets of ,fuller's pasteboard form'd into a tube1 near #aj feet long and a foot diameter4 ,it is cover'd with ,dutch emboss'd paper1 almost totally gilt4 ,this large metallic surface supports a much greater electrical atmosphere than a rod of iron of #ej times the weight would do4 ,it is suspended by silk lines1 and when charg'd will strike at near two inches distance1 a pretty hard stroke so as to make one's knuckle ach4 ,let a person standing on the floor present the point of a needle at #ab or more inches distance from it1 and while the needle is so presented1 the conductor cannot be charged1 the point drawing off the fire as fast as it is thrown on by the electrical globe4 ,let it be charged1 and then present the point at the same distance1 and it will suddenly be discharged4 ,in the dark you may see a light on the point1 when the experiment is made4 ,and if the person holding the point stands upon wax1 he will be electrified by receiving the fire at that distance4 ,attempt to draw off the electricity with a blunt body1 as a bolt of iron round at the end and smooth 7a silversmith's iron punch1 inch-thick1 is what ,i use7 and you must bring it within the distance of three inches before you can do it1 and then it is done with a stroke and crack4 ,as the pasteboard tube hangs loose on silk lines1 when you approach it with the punch iron1 it likewise will move towards the punch1 being attracted while it is charged2 but if at the same instant a point be presented as before1 it retires again1 for the point discharges it4 ,take a pair of large brass scales1 of two or more feet beam1 the cords of the scales being silk4 ,suspend the beam by a packthread from the cieling1 so that the bottom of the scales may be about a foot from the floor3 ,the scales will move round in a circle by the untwisting of the packthread4 ,set the iron punch on the end upon the floor1 in such a place as that the scales may pass over it in making their circle3 ,then electrify one scale by applying the wire of a charged phial to it4 ,as they move round1 you see that scale draw nigher to the floor1 and dip more when it comes over the punch2 and if that be placed at a proper distance1 the scale will snap and discharge its fire into it4 ,but if a needle be stuck on the end of the punch1 its point upwards1 the scale1 instead of drawing nigh to the punch and snapping1 discharges its fire silently through the point1 and rises higher from the punch4 ,nay1 even if the needle be placed upon the floor near the punch1 its point upwards1 the end of the punch1 tho' so much higher than the needle1 will not attract the scale and receive its fire1 for the needle will get it and convey it away1 before it comes nigh enough for the punch to act4 ,and this is constantly observable in these experiments1 that the greater quantity of electricity on the pasteboard tube1 the farther it strikes or discharges its fire1 and the point likewise will draw it off at a still greater distance4 ,now if the fire of electricity and that of lightening be the same1 as ,i have endeavour'd to show at large in a former paper1 this pasteboard tube and these scales may represent electrified clouds4 ,if a tube of only #aj feet long will strike and discharge its fire on the punch at two or three inches distance1 an electrified cloud of perhaps #aj1jjj acres1 may strike and discharge on the earth at a proportionably greater distance4 ,the horizontal motion of the scales over the floor1 may represent the motion of the clouds over the earth2 and the erect iron punch1 a hill or high building2 and then we see how electrified clouds passing over hills or high buildings at too great a height to strike1 may be attracted lower till within their striking distance4 ,and lastly1 if a needle fix'd on the punch with its point upright1 or even on the floor below the punch1 will draw the fire from the scale silently at a much greater than the striking distance1 and so prevent its descending towards the punch2 or if in its course it would have come nigh enough to strike1 yet being first deprived of its fire it cannot1 and the punch is thereby secured from the stroke4 ,i say1 if these things are so1 may not the knowledge of this power of points be of use to mankind1 in preserving houses1 churches1 ships1 c4 from the stroke of lightning1 by directing us to fix on the highest parts of those edifices1 upright rods of iron made sharp as a needle1 and gilt to prevent rusting1 and from the foot of those rods a wire down the outside of the building into the ground1 or down round one of the shrouds of a ship1 and down her side till it reaches the water8 ,would not these pointed rods probably draw the electrical fire silently out of a cloud before it came nigh enough to strike1 and thereby secure us from that most sudden and terrible mischief8 #ba4 ,to determine the question1 whether the clouds that contain lightning are electrified or not1 ,i would propose an experiment to be try'd where it may be done conveniently4 ,on the top of some high tower or steeple1 place a kind of sentry-box1 7as in ,,fig4 #i47 big enough to contain a man and an electrical stand4 ,from the middle of the stand1 let an iron rod rise and pass bending out of the door1 and then upright #bj or #cj feet1 pointed very sharp at the end4 ,if the electrical stand be kept clean and dry1 a man standing on it when such clouds are passing low1 might be electrified and afford sparks1 the rod drawing fire to him from a cloud4 ,if any danger to the man should be apprehended 7though ,i think there would be none7 let him stand on the floor of his box1 and now and then bring near to the rod1 the loop of a wire that has one end fastened to the leads1 he holding it by a wax handle2 so the sparks1 if the rod is electrified1 will strike from the rod to the wire1 and not affect him4 #bb4 ,before ,i leave this subject of lightning1 ,i may mention some other similarities between the effects of that1 and these of electricity4 ,lightning has often been known to strike people blind4 ,a pigeon that we struck dead to appearance by the electrical shock1 recovering life1 droop'd about the yard several days1 eat nothing though crumbs were thrown to it1 but declined and died4 ,we did not think of its being deprived of sight2 but afterwards a pullet struck dead in like manner1 being recovered by repeatedly blowing into its lungs1 when set down on the floor1 ran headlong against the wall1 and on examination appeared perfectly blind4 ,hence we concluded that the pigeon also had been absolutely blinded by the shock4 ,the biggest animal we have yet killed or try'd to kill with the electrical stroke1 was a well-grown pullet4 #bc4 ,reading in the ingenious ,dr4 ,hales's account of the thunder storm at ,stretham1 the effect of the lightning in stripping off all the paint that had covered a gilt moulding of a pannel of wainscot1 without hurting the rest of the paint1 ,i had a mind to lay a coat of paint over the filleting of gold on the cover of a book1 and try the effect of a strong electrical flash sent through that gold from a charged sheet of glass4 ,but having no paint at hand1 ,i pasted a narrow strip of paper over it2 and when dry1 sent the flash through the gilding2 by which the paper was torn off from end to end1 with such force1 that it was broke in several places1 and in others brought away part of the grain of the ,turky-leather in which it was bound2 and convinced me1 that had it been painted1 the paint would have been stript off in the same manner with that on the wainscot at ,stretham4 #bd4 ,lightning melts metals1 and ,i hinted in my paper on that subject1 that ,i suspected it to be a cold fusion2 ,i do not mean a fusion by force of cold1 but a fusion without heat4 ,we have also melted gold1 silver1 and copper1 in small quantities1 by the electrical flash4 ,the manner is this3 ,take leaf gold1 leaf silver1 or leaf gilt copper1 commonly called leaf brass or ,dutch gold3 cut off from the leaf long narrow strips the breadth of a straw4 ,place one of these strips between two strips of smooth glass that are about the width of your finger4 ,if one strip of gold1 the length of the leaf1 be not long enough for the glass1 add another to the end of it1 so that you may have a little part hanging out loose at each end of the glass4 ,bind the pieces of glass together from end to end with strong silk thread2 then place it so as to be part of an electrical circle1 7the ends of gold hanging out being of use to join with the other parts of the circle7 and send the flash through it1 from a large electrified jar or sheet of glass4 ,then if your strips of glass remain whole1 you will see that the gold is missing in several places1 and instead of it a metallic stain on both the glasses2 the stains on the upper and under glass exactly similar in the minutest stroke1 as may be seen by holding them to the light2 the metal appeared to have been not only melted1 but even vitrified1 or otherwise so driven into the pores of the glass1 as to be protected by it from the action of the strongest ,aqua ,fortis and ,ag3 ,regia4 ,i send you enclosed two little pieces of glass with these metallic stains upon them1 which cannot be removed without taking part of the glass with them4 ,sometimes the stain spreads a little wider than the breadth of the leaf1 and looks brighter at the edge1 as by inspecting closely you may observe in these4 ,sometimes the glass breaks to pieces3 once the upper glass broke into a thousand pieces1 looking like coarse salt4 ,these pieces ,i send you1 were stain'd with ,dutch gold4 ,true gold makes a darker stain1 somewhat reddish2 silver1 a greenish stain4 ,we once took two pieces of thick looking-glass1 as broad as a ,gunter's scale1 and #f inches long2 and placing leaf gold between them1 put them betwixt two smoothly plain'd pieces of wood1 and fix'd them tight in a book-binder's small press2 yet though they were so closely confined1 the force of the electrical shock shivered the glass into many pieces4 ,the gold was melted and stain'd into the glass as usual4 ,the circumstances of the breaking of the glass differ much in making the experiment1 and sometimes it does not break at all3 but this is constant1 that the stains in the upper and under pieces are exact counterparts of each other4 ,and though ,i have taken up the pieces of glass between my fingers immediately after this melting1 ,i never could perceive the least warmth in them4 #be4 ,in one of my former papers1 ,i mention'd1 that gilding on a book1 though at first it communicated the shock perfectly well1 yet fail'd after a few experiments1 which we could not account for4 ,we have since found1 that one strong shock breaks the continuity of the gold in the filleting1 and makes it look rather like dust of gold1 abundance of its parts being broken and driven off2 and it will seldom conduct above one strong shock4 ,perhaps this may be the reason2 when there is not a perfect continuity in the circle1 the fire must leap over the vacancies2 there is a certain distance which it is able to leap over according to its strength2 if a number of small vacancies1 though each be very minute1 taken together exceed that distance1 it cannot leap over them1 and so the shock is prevented4 #bf4 ,from the before mentioned law of electricity1 that points1 as they are more or less acute1 draw on and throw off the electrical fluid with more or less power1 and at greater or less distances1 and in larger or smaller quantities in the same time1 we may see how to account for the situation of the leaf of gold suspended between two plates1 the upper one continually electrified1 the under one in a person's hand standing on the floor4 ,when the upper plate is electrified1 the leaf is attracted and raised towards it1 and would fly to that plate were it not for its own points4 ,the corner that happens to be uppermost when the leaf is rising1 being a sharp point1 from the extream thinness of the gold1 draws and receives at a distance a sufficient quantity of the electrical fluid to give itself an electrical atmosphere1 by which its progress to the upper plate is stopt1 and it begins to be repelled from that plate1 and would be driven back to the under plate1 but that its lowest corner is likewise a point1 and throws off or discharges the overplus of the leaf's atmosphere1 as fast as the upper corner draws it on4 ,were these two points perfectly equal in acuteness1 the leaf would take place exactly in the middle space1 for its ,weight is a trifle1 compared to the power acting on it3 ,but it is generally nearest the unelectrified plate1 because1 when the leaf is offered to the electrified plate at a distance1 the sharpest point is commonly first affected and raised towards it2 so that point1 from its greater acuteness1 receiving the fluid faster than its opposite can discharge it at equal distances1 it retires from the electrified plate1 and draws nearer to the unelectrified plate1 till it comes to a distance where the discharge can be exactly equal to the receipt1 the latter being lessened1 and the former encreased2 and there it remains as long as the globe continues to supply fresh electrical matter4 ,this will appear plain1 when the difference of acuteness in the corners is made very great4 ,cut a piece of ,dutch gold 7which is fittest for these experiments on account of its greater strength7 into the form of ,,fig4 #aj the upper corner a right angle1 the two next obtuse angles1 and the lowest a very acute one2 and bring this on your plate under the electrified plate1 in such a manner as that the right-angled part may be first raised 7which is done by covering the acute part with the hollow of your hand7 and you will see this leaf take place much nearer to the upper than to the under plate2 because1 without being nearer1 it cannot receive so fast at its right-angled point1 as it can discharge at its acute one4 ,turn this leaf with the acute part uppermost1 and then it takes place nearest the unelectrified plate1 because otherwise it receives faster at its acute point than it can discharge at its right-angled one4 ,thus the difference of distance is always proportioned to the difference of acuteness4 ,take care in cutting your leaf to leave no little ragged particles on the edges1 which sometimes form points where you would not have them4 ,you may make this figure so acute below and blunt above1 as to need no under plate1 it discharging fast enough into the air4 ,when it is made narrower1 as the figure between the pricked lines1 we call it the ,golden ,fish1 from its manner of acting4 ,for if you take it by the tail1 and hold it at a foot or greater horizontal distance from the prime conductor1 it will1 when let go1 fly to it with a brisk but wavering motion1 like that of an eel through the water2 it will then take place under the prime conductor1 at perhaps a quarter or half an inch distance1 and keep a continual shaking of its tail like a fish1 so that it seems animated4 ,turn its tail towards the prime conductor1 and then it flies to your finger1 and seems to nibble it4 ,and if you hold a plate under it at six or eight inches distance1 and cease turning the ,globe1 when the electrical atmosphere of the conductor grows small1 it will descend to the plate and swim back again several times with the same fish-like motion1 greatly to the entertainment of spectators4 ,by a little practice in blunting or sharpening the heads or tails of these figures1 you may make them take place as desired1 nearer1 or farther from the electrified plate4 #bg4 ,it is said in section #h1 of this paper1 that all kinds of common matter are supposed not to attract the electrical fluid with equal strength2 and that those called electrics per se1 as glass1 c4 attract and retain it strongest1 and contain the greatest quantity4 ,this latter position may seem a paradox to some1 being contrary to the hitherto received opinion2 and therefore ,i shall now endeavour to explain it4 #bh4 ,in order to this1 let it first be considered1 that we cannot1 by any means we are yet acquainted with1 force the electrical fluid thro' glass4 ,i know it is commonly thought that it easily pervades glass1 and the experiment of a feather suspended by a thread in a bottle hermetically sealed1 yet moved by bringing a nibbed tube near the outside of the bottle1 is alledged to prove it4 ,but1 if the electrical fluid so easily pervades glass1 how does the vial become charged 7as we term it7 when we hold it in our hands8 ,would not the fire thrown in by the wire pass through to our hands1 and so escape into the floor8 ,would not the bottle in that case be left just as we found it1 uncharged1 as we know a metal bottle so attempted to be charged would be8 ,indeed1 if there be the least crack1 the minutest solution of continuity in the glass1 though it remains so tight that nothing else we know of will pass1 yet the extremely subtile electrical fluid flies through such a crack with the greatest freedom1 and such a bottle we know can never be charged3 ,what then makes the difference between such a bottle and one that is sound1 but this1 that the fluid can pass through the one1 and not through the other8#h #bi4 ,it is true there is an experiment that at first sight would be apt to satisfy a slight observer1 that the fire thrown into the bottle by the wire1 does really pass thro' the glass4 ,it is this3 place the bottle on a glass stand1 under the prime conductor2 suspend a bullet by a chain from the prime conductor1 till it comes within a quarter of an inch right over the wire of the bottle2 place your knuckle on the glass stand1 at just the same distance from the coating of the bottle1 as the bullet is from its wire4 ,now let the globe be turned1 and you see a spark strike from the bullet to the wire of the bottle1 and the same instant you see and feel an exactly equal spark striking from the coating on your knuckle1 and so on spark for spark4 ,this looks as if the whole received by the bottle was again discharged from it4 ,and yet the bottle by this means is charged6#i ,and therefore the fire that thus leaves the bottle1 though the same in quantity1 cannot be the very same fire that entered at the wire2 for if it were1 the bottle would remain uncharged4 #cj4 ,if the fire that so leaves the bottle be not the same that is thrown in through the wire1 it must be fire that subsisted in the bottle1 7that is1 in the glass of the bottle7 before the operation began4 #ca4 ,if so1 there must be a great quantity in glass1 because a great quantity is thus discharged even from very thin glass4 #cb4 ,that this electrical fluid or fire is strongly attracted by glass1 we know from the quickness and violence with which it is resumed by the part that had been deprived of it1 when there is an opportunity4 ,and by this1 that we cannot from a mass of glass draw a quantity of electrical fire1 or electrify the whole mass minus1 as we can a mass of metal4 ,we cannot lessen or increase its whole quantity1 for the quantity it has it holds2 and it has as much as it can hold4 ,its pores are filled with it as full as the mutual repellency of the particles will admit2 and what is already in1 refuses1 or strongly repels1 any additional quantity4 ,nor have we any way of moving the electrical fluid in glass1 but one2 that is1 by covering part of the two surfaces of thin glass with non-electrics1 and then throwing an additional quantity of this fluid on one surface1 which spreading in the non-electric1 and being bound by it to that surface1 acts by its repelling force on the particles of the electrical fluid contained in the other surface1 and drives them out of the glass into the non-electric on that side1 from whence they are discharged1 and then those added on the charged side can enter4 ,but when this is done1 there is no more in the glass1 nor less than before1 just as much having left it on one side as it received on the other4 ,illustration #cc4 ,i feel a want of terms here1 and doubt much whether ,i shall be able to make this part intelligible4 ,by the word surface1 in this case1 ,i do not mean mere length and breadth without thickness2 but when ,i speak of the upper or under surface of a piece of glass1 the outer or inner surface of the vial1 ,i mean length1 breadth1 and half the thickness1 and beg the favour of being so understood4 ,now1 ,i suppose1 that glass in its first principles1 and in the ,furnace1 has no more of this electrical fluid than other common matter3 ,that when it is blown1 as it cools1 and the particles of common fire leave it1 its pores become a vacuum3 ,that the component parts of glass are extremely small and fine1 ,i guess from its never showing a rough face when it breaks1 but always a polish2 and from the smallness of its particles ,i suppose the pores between them must be exceeding small1 which is the reason that ,aqua-fortis1 nor any other menstruum we have1 can enter to separate them and dissolve the substance2 nor is any fluid we know of1 fine enough to enter1 except common fire1 and the electrical fluid4 ,now the departing fire leaving a vacuum1 as aforesaid1 between these pores1 which air nor water are fine enough to enter and fill1 the electrical fluid 7which is every where ready in what we call the non-electrics1 and in the non-electric ,mixtures that are in the air17 is attracted in3 yet does not become fixed with the substance of the glass1 but subsists there as water in a porous stone1 retained only by the attraction of the fixed parts1 itself still loose and a fluid4 ,but ,i suppose farther1 that in the cooling of the glass1 its texture becomes closest in the middle1 and forms a kind of partition1 in which the pores are so narrow1 that the particles of the electrical fluid1 which enter both surfaces at the same time1 cannot go through1 or pass and repass from one surface to the other1 and so mix together2 yet1 though the particles of electrical fluid1 imbibed by each surface1 cannot themselves pass through to those of the other1 their repellency can1 and by this means they act on one another4 ,the particles of the electrical fluid have a mutual repellency1 but by the power of attraction in the glass they are condensed or forced nearer to each other4 ,when the glass has received and1 by its attraction1 forced closer together so much of this electrified fluid1 as that the power of attracting and condensing in the one1 is equal to the power of expansion in the other1 it can imbibe no more1 and that remains its constant whole quantity2 but each surface would receive more1 if the repellency of what is in the opposite surface did not resist its entrance4 ,the quantities of this fluid in each surface being equal1 their repelling action on each other is equal2 and therefore those of one surface cannot drive out those of the other3 but1 if a greater quantity is forced into one surface than the glass would naturally draw in2 this increases the repelling power on that side1 and overpowering the attraction on the other1 drives out part of the fluid that had been imbibed by that surface1 if there be any non-electric ready to receive it3 such there is in all cases where glass is electrified to give a shock4 ,the surface that has been thus emptied by having its electrical fluid driven out1 resumes again an equal quantity with violence1 as soon as the glass has an opportunity to discharge that over-quantity more than it could retain by attraction in its other surface1 by the additional repellency of which the vacuum had been occasioned4 ,for experiments favouring 7if ,i may not say confirming7 this hypothesis1 ,i must1 to avoid repetition1 beg leave to refer you back to what is said of the electrical phial in my former papers4 #cd4 ,let us now see how it will account for several other appearances4--,glass1 a body extremely elastic 7and perhaps its elasticity may be owing in some degree to the subsisting of so great a quantity of this repelling fluid in its pores7 must1 when rubbed1 have its rubbed surface somewhat stretched1 or its solid parts drawn a little farther asunder1 so that the vacancies in which the electrical fluid resides1 become larger1 affording room for more of that fluid1 which is immediately attracted into it from the cushion or hand rubbing1 they being supply'd from the common stock4 ,but the instant the parts of the glass so open'd and fill'd have pass'd the friction1 they close again1 and force the additional quantity out upon the surface1 where it must rest till that part comes round to the cushion again1 unless some non electric 7as the prime conductor7 first presents to receive it4#aj ,but if the inside of the globe be lined with a non-electric1 the additional repellency of the electrical fluid1 thus collected by friction on the rubb'd part of the globe's outer surface1 drives an equal quantity out of the inner surface into that non-electric lining1 which receiving it1 and carrying it away from the rubb'd part into the common mass1 through the axis of the globe and frame of the machine1 the new collected electrical fluid can enter and remain in the outer surface1 and none of it 7or a very little7 will be received by the prime conductor4 ,as this charg'd part of the globe comes round to the cushion again1 the outer surface delivers its overplus fire into the cushion1 the opposite inner surface receiving at the same time an equal quantity from the floor4 ,every electrician knows that a globe wet within will afford little or no fire1 but the reason has not before been attempted to be given1 that ,i know of4 #cd4 ,so if a tube lined with a #aanon-electric1 be rubb'd1 little or no fire is obtained from it4 ,what is collected from the hand in the downward rubbing stroke1 entering the pores of the glass1 and driving an equal quantity out of the inner surface into the non-electric lining3 and the hand in passing up to take a second stroke1 takes out again what had been thrown into the outer surface1 and then the inner surface receives back again what it had given to the non-electric lining4 ,thus the particles of electrical fluid belonging to the inside surface go in and out of their pores every stroke given to the tube4 ,put a wire into the tube1 the inward end in contact with the non-electric lining1 so it will represent the ,leyden bottle4 ,let a second person touch the wire while you rub1 and the fire driven out of the inward surface when you give the stroke1 will pass through him into the common mass1 and return through him when the inner surface resumes its quantity1 and therefore this new kind of ,leyden bottle cannot so be charged4 ,but thus it may3 after every stroke1 before you pass your hand up to make another1 let the second person apply his finger to the wire1 take the spark1 and then withdraw his finger2 and so on till he has drawn a number of sparks2 thus will the inner surface be exhausted1 and the outer surface charged2 then wrap a sheet of gilt paper close round the outer surface1 and grasping it in your hand you may receive a shock by applying the finger of the other hand to the wire3 for now the vacant pores in the inner surface resume their quantity1 and the overcharg'd pores in the outer surface discharge that overplus2 the equilibrium being restored through your body1 which could not be restored through the glass4#ab ,if the tube be exhausted of air1 a non electric lining in contact with the wire is not necessary2 for in vacuo1 the electrical fire will fly freely from the inner surface1 without a non-electric conductor3 but air resists its motion2 for being itself an electric per se1 it does not attract it1 having already its quantity4 ,so the air never draws off an electric atmosphere from any body1 but in proportion to the non-electrics mix'd with it3 it rather keeps such an atmosphere confin'd1 which from the mutual repulsion of its particles1 tends to dissipation1 and would immediately dissipate in vacuo4--,and thus the experiment of the feather inclosed in a glass vessel hermetically sealed1 but moving on the approach of the rubbed tube1 is explained3 ,when an additional quantity of the electrical fluid is applied to the side of the vessel by the atmosphere of the tube1 a quantity is repelled and driven out of the inner surface of that side into the vessel1 and there affects the feather1 returning again into its pores1 when the tube with its atmosphere is withdrawn2 not that the particles of that atmosphere did themselves pass through the glass to the feather4----,and every other appearance ,i have yet seen1 in which glass and electricity are concern'd1 are1 ,i think1 explain'd with equal ease by the same hypothesis4 ,yet1 perhaps1 it may not be a true one1 and ,i shall be obliged to him that affords me a better4 #ce4 ,thus ,i take the difference between non electrics and glass1 an electric per se1 to consist in these two particulars4 #ast1 ,that a non-electric easily suffers a change in the quantity of the electrical fluid it contains4 ,you may lessen its whole quantity by drawing out a part1 which the whole body will again resume2 but of glass you can only lessen the quantity contain'd in one of its surfaces2 and not that1 but by supplying an equal quantity at the same time to the other surface2 so that the whole glass may always have the same quantity in the two surfaces1 their two different quantities being added together4 ,and this can only be done in glass that is thin2 beyond a certain thickness we have yet no power that can make this change4 ,and1 #b;dly1 that the electrical fire freely removes from place to place1 in and through the substance of a non-electric1 but not so through the substance of glass4 ,if you offer a quantity to one end of a long rod of metal1 it receives it1 and when it enters1 every particle that was before in the rod1 pushes its neighbour quite to the further end1 where the overplus is discharg'd2 and this instantaneously where the rod is part of the circle in the experiment of the shock4 ,but glass1 from the smallness of its pores1 or stronger attraction of what it contains1 refuses to admit so free a motion2 a glass rod will not conduct a shock1 nor will the thinnest glass suffer any particle entring one of its surfaces to pass thro' to the other4 #cf4 ,hence we see the impossibility of success1 in the experiments propos'd1 to draw out the effluvial virtues of a non-electric1 as cinnamon for instance1 and mixing them with the electrical fluid1 to convey them with that into the body1 by including it in the globe1 and then applying friction1 etc4 ,for though the effluvia of cinnamon1 and the electrical fluid should mix within the globe1 they would never come out together through the pores of the glass1 and so go to the prime conductor2 for the electrical fluid itself cannot come through2 and the prime conductor is always supply'd from the cushion1 and that from the floor4 ,and besides1 when the globe is filled with cinnamon1 or other non-electric1 no electrical fluid can be obtain'd from its outer surface1 for the reason before-mentioned4 ,i have try'd another way1 which ,i thought more likely to obtain a mixture of the electrical and other effluvia together1 if such a mixture had been possible4 ,i placed a glass plate under my cushion1 to cut off the communication between the cushion and floor2 then brought a small chain from the cushion into a glass of oil of turpentine1 and carried another chain from the oil of turpentine to the floor1 taking care that the chain from the cushion to the glass touch'd no part of the frame of the machine4 ,another chain was fix'd to the prime conductor1 and held in the hand of a person to be electrised4 ,the ends of the two chains in the glass were near an inch distant from each other1 the oil of turpentine between4 ,now the globe being turn'd1 could draw no fire from the floor through the machine1 the communication that way being cut off by the thick glass plate under the cushion3 it must then draw it through the chains whose ends were dipt in the oil of turpentine4 ,and as the oil of turpentine being an electric per se1 would not conduct what came up from the floor1 was obliged to jump from the end of one chain1 to the end of the other1 through the substance of that oil1 which we could see in large sparks2 and so it had a fair opportunity of seizing some of the finest particles of the oil in its passage1 and carrying them off with it3 but no such effect followed1 nor could ,i perceive the least difference in the smell of the electrical effluvia thus collected1 from what it has when collected otherwise2 nor does it otherwise affect the body of a person electrised4 ,i likewise put into a phial1 instead of water1 a strong purgative liquid1 and then charged the phial1 and took repeated shocks from it1 in which case every particle of the electrical fluid must1 before it went through my body1 have first gone through the liquid when the phial is charging1 and returned through it when discharging1 yet no other effect followed than if it had been charged with water4 ,i have also smelt the electrical fire when drawn through gold1 silver1 copper1 lead1 iron1 wood1 and the human body1 and could perceive no difference2 the odour is always the same where the spark does not burn what it strikes2 and therefore ,i imagine it does not take that smell from any quality of the bodies it passes through4 ,and indeed1 as that smell so readily leaves the electrical matter1 and adheres to the knuckle receiving the sparks1 and to other things2 ,i suspect that it never was connected with it1 but arises instantaneously from something in the air acted upon by it4 ,for if it was fine enough to come with the electrical fluid through the body of one person1 why should it stop on the skin of another8 ,but ,i shall never have done1 if ,i tell you all my conjectures1 thoughts1 and imaginations1 on the nature and operations of this electrical fluid1 and relate the variety of little experiments we have try'd4 ,i have already made this paper too long1 for which ,i must crave pardon1 not having now time to make it shorter4 ,i shall only add1 that as it has been observed here that spirits will fire by the electrical spark in the summer time1 without heating them1 when ,fahrenheit's thermometer is above #gj2 so1 when colder1 if the operator puts a small flat bottle of spirits in his bosom1 or a close pocket1 with the spoon1 some little time before he uses them1 the heat of his body will communicate warmth more than sufficient for the purpose4 ,,additional ,,experiment1 proving that the ,leyden ,bottle has no more electrical ,fire in it when charged1 than before2 nor less when discharged3 ,that in discharging1 the ,fire does not issue from the ,wire and the ,coating at the same ,time1 as some have thought1 but that the ,coating always receives what is discharged by the ,wire1 or an equal ,quantity2 the outer ,surface being always in a negative ,state of ,electricity1 when the inner ,surface is in a positive ,state4 ,place a thick plate of glass under the rubbing cushion1 to cut off the communication of electrical fire from the floor to the cushion2 then1 if there be no fine points or hairy threads sticking out from the cushion1 or from the parts of the machine opposite to the cushion1 7of which you must be careful7 you can get but a few sparks from the prime conductor1 which are all the cushion will part with4 ,hang a phial then on the prime conductor1 and it will not charge1 tho' you hold it by the coating4----,but ,form a communication by a chain from the coating to the cushion1 and the phial will charge4 ,for the globe then draws the electrical fire out of the outside surface of the phial1 and forces it1 through the prime conductor and wire of the phial1 into the inside surface4 ,thus the bottle is charged with its own fire1 no other being to be had while the glass plate is under the cushion4 ,hang two cork balls by flaxen threads to the prime conductor2 then touch the coating of the bottle1 and they will be electrified and recede from each other4 ,for just as much fire as you give the coating1 so much is discharged through the wire upon the prime conductor1 whence the cork balls receive an electrical atmosphere4 ,but ,take a wire bent in the form of a ,c1 with a stick of wax fixed to the outside of the curve1 to hold it by2 and apply one end of this wire to the coating1 and the other at the same time to the prime conductor1 the phial will be discharged2 and if the balls are not electrified before the discharge1 neither will they appear to be so after the discharge1 for they will not repel each other4 ,now if the fire discharged from the inside surface of the bottle through its wire1 remained on the prime conductor1 the balls would be electrified and recede from each other4 ,if the phial really exploded at both ends1 and discharged fire from both coating and wire1 the balls would be more electrified and recede farther3 for none of the fire can escape1 the wax handle preventing4 ,but if the fire1 with which the inside surface is surcharged1 be so much precisely as is wanted by the outside surface1 it will pass round through the wire fixed to the wax handle1 restore the equilibrium in the glass1 and make no alteration in the state of the prime conductor4 ,accordingly we find1 that if the prime conductor be electrified1 and the cork balls in a state of repellency before the bottle is charged1 they continue so afterwards4 ,if not1 they are not electrified by that discharge4 ,,corrections and ,,additions to the ,,preceding ,,papers4 ,page #b1 ,sect4 #a4 ,we since find1 that the fire in the bottle is not contained in the non-electric1 but in the glass4 ,all that is after said of the top and bottom of the bottle1 is true of the inside and outside surfaces1 and should have been so expressed4 ,see ,sect4 #af1 p4 #af4 ,page #f1 ,line #ac4 ,the equilibrium will soon be restored but silently1 etc4 ,this must have been a mistake4 ,when the bottle is full charged1 the crooked wire cannot well be brought to touch the top and bottom so quick1 but that there will be a loud spark2 unless the points be sharp1 without loops4 ,ibid4 line ult4 ,outside3 add1 such moisture continuing up to the cork or wire4 ,page #ab1 line #ad4 ,by candle-light etc4 ,from some observations since made1 ,i am inclined to think1 that it is not the light1 but the smoke or non-electric effluvia from the candle1 coal1 and red-hot iron1 that carry off the electrical fire1 being first attracted and then repelled4 ,page #ac1 line #ae4 ,windmil wheels1 c4 ,we afterwards discovered1 that the afflux or efflux of the electrical fire1 was not the cause of the motions of those wheels1 but various circumstances of attraction and repulsion4 ,page #af1 line #ba4 ,let ,a and ,b stand on wax1 c4 ,we soon found that it was only necessary for one of them to stand on wax4 ,page #ai4 in the title r4 on4 ,page #bd1 line #ab4 r4 contact1 line #bd4 confined4 ,page #be1 line #aj4 for stand r4 hand4 ,page #bh1 line #b4 ,the consequence might perhaps be fatal1 c4 ,we have found it fatal to small animals1 but 'tis not strong enough to kill large ones4 ,the biggest we have killed is a hen4 ,page #ca1 line #bj4 ,ringing of chimes1 c4 ,this is since done4 ,page #cc1 line #bb4 ,fails after ten or twelve experiments4 ,this was by a small bottle4 ,and since found to fail after with a large glass4 ,page #dj1 sect4 #ej1 #ea4 ,spirits must be heated before we can fire them1 c4 ,we have since fired spirits without heating1 when the weather is warm4 ,,finis4 ,,books ,printed and ,sold by ,,edward ,,cave1 at ,st4 ,john's ,gate4 ,i4 ,geography ,reform'd3 ,or1 ,a new ,system of ,general ,geography according to an accurate ,analysis of the ,science1 augmented with several necessary ,branches omitted by former ,authors4 ,in four ,parts4 #a4 ,of the ,nature and ,principles of ,geography2 its ancient and present ,state in all ,nations1 its ,usefulness to ,persons of all ,professions1 and the ,method of studying it2 with its ,analysis or ,division into ,species1 according to former ,authors1 and a new ,plan1 shewing the ,errors and ,defects of those by ,varenius1 ,sanson1 la ,mattiniere1 ,pere ,castel1 etc4 #b4 ,of ,mathematical ,geography and its ,branches1 ,astronomical and ,geometrical3 ,shewing the several ,divisions of the ,earth by ,regions1 ,hemispheres1 ,zones1 ,climates1 ,meridians and ,parallels1 etc4 #c4 ,historical ,geography and its ,species1 ,natural2 ,civil2 ,ecclesiastical2 ,national2 ,periodical1 ancient1 middle1 modern2 ,parallel and ,critical4 #d4 ,of ,technical ,geography and its ,branches2 ,representatory1 by ,globes and ,maps2 ,synoptical1 by ,tables2 and ,explanatory1 by ,systems and ,dictionaries4 ,under each ,branch is given an ,account of its ,object and ,use1 an ,explanation of the ,terms1 the ,history of its ,rise and ,progress1 with ,rules for exhibiting it to the best ,advantage4 ,the whole illustrated with ,notes and ,references to the principal ,geographers whose different ,sentiments are cited and examined4 ,designed for the ,use of the ,curious in general1 and ,students in particular4 ,there is added a copious ,index of the ,terms contained in the ,work1 answering the ,end of a ,dictionary of ,general ,geography4 ,the ,second ,edition4 ,price #cs4 #f;d4 bound4 ,,ii4 ,memoirs of the ,royal ,academy of ,surgery at ,paris4 ,containing ,remarks1 with practical ,observations1 on ,tumours of the ,gall ,bladder1 on the ,thigh1 and the ,trachea ,arteria2 on the ,use of the ,trepan2 of ,wounds in the ,brain1 ,exfoliation of the ,cranium1 ,cases of pregnant ,women1 faulty ,anus in new born ,children1 ,abscesses in the ,fundament1 ,stones encysted in the ,bladder1 ,obstructions to the ,ejaculation of the ,semen1 an inverted ,eyelid1 extraneous ,bodies retained in the ,oesophagus1 discharged through ,abscesses2 of ,bronchotomy1 ,gastrotomy1 native ,hare-lips2 of the ,csarean ,operation2 a new ,method of extracting the ,stone from the ,bladder1 on a ,cancer of the ,breast1 an elastic ,truss for ,hernias1 remarkable ,hernias of the ,stomach1 and through the ,foramen ,ovale4 ,of a pulmonary ,abscess1 c4 ,translated from the ,original1 dedicated to the ,french ,king4 ,in two ,volumes1 ,octavo4 ,price #hs4 ,,iii4 ,a ,treatise of ,comets1 containing1 #a4 ,an ,explication of all the various ,appearances of the late ,comet1 both in its own ,trajectory and the ,firmament of fixt ,stars1 to its setting in the ,sun ,beams3 ,illustrated with a ,plan of the ,earth's and ,comet's ,orbits4 #b4 ,the ,history of ,comets from the earliest ,account of those kinds of ,planets to the present ,time2 wherein the ,sentiments of the ,ancient and ,modern ,philosophers are occasionally displayed4 ,with ,remarks on the ,intentional ,end of ,comets1 and the ,nature and ,design of ,saturn's ,ring4 ,the ,distance1 ,velocity1 ,size1 ,solidity1 and other ,properties of those ,bodies considered2 and the wonderful ,phnomena of their ,tails and ,atmospheres accounted for4 ,illustrated also by a ,copper-,plate4 ,by ,g4 ,smith4 ,price #as4 ,,iv4 ,the ,natural ,history of ,mount ,vesuvius1 with the ,explanation of the various ,phenomena that usually attend the ,eruptions of this celebrated ,volcano4 ,translated from the original ,italian1 composed by the ,royal ,academy of ,sciences at ,naples1 by ,order of the ,king of the ,two ,sicilies4 ,price #bs4 stitch'd1 or #bs4 #f;d4 bound4 ,,footnotes4 #a ,we suppose every particle of sand1 moisture1 or smoke1 being first attracted and then repelled1 carries off with it a portion of the electrical fire2 but that the same still subsists in those particles1 till they communicate it to something else2 and that it is never really destroyed4--,so when water is thrown on common fire1 we do not imagine the element is thereby destroyed or annihilated1 but only dispersed1 each particle of water carrying off in vapour its portion of the fire1 which it had attracted and attached to itself4 #b ,our tubes are made here of green glass1 #bg or #cj inches long1 as big as can be grasped4 ,electricity is so much in vogue1 that above one hundred of them have been sold within these four months past4 #c ,to charge a bottle commodiously through the coating1 place it on a glass stand2 form a communication from the prime conductor to the coating1 and another from the hook to the wall or floor4 ,when it is charged1 remove the latter communication before you take hold of the bottle1 otherwise great part of the fire will escape by it4 #d ,the river that washes one side of ,philadelphia1 as the ,delaware does the other2 both are ornamented with the summer habitations1 of the citizens1 and the agreeable mansions of the principal people of this colony4 #e ,an electrified bumper1 is a small thin glass tumbler1 near filled with wine1 and electrified as the bottle4 ,this when brought to the lips gives a shock1 if the party be close shaved1 and does not breathe on the liquor4 #f ,thunder-gusts are sudden storms of thunder and lightning1 which are frequently of short duration1 but sometimes produce mischievous effects4 #g ,see the ingenious essays on electricity in the ,transactions1 by ,mr ,ellicot4 #h ,see the first sixteen ,sections of my former ,paper1 called ,farther ,experiments1 c4 #i ,see #aj of ,farther ,experiments1 c4 #aj ,in the dark the electrical fluid may be seen on the cushion in two semi-circles or half-moons1 one on the fore part1 the other on the back part of the cushion1 just where the globe and cushion separate4 ,in the fore crescent the fire is passing out of the cushion into the glass2 in the other it is leaving the glass1 and returning into the back part of the cushion4 ,when the prime conductor is apply'd to take it off the glass1 the back crescent disappears4 #aa ,gilt paper1 with the gilt face next the glass1 does well4 #ab ,see farther experiments1 #ae4