,transcriber ,note ,text emphasis is denoted as ,italics and ,bold4 ,,the ,,dry ,,collodion ,,process4 ,,by ,,charles ,a4 ,,long4 ,,third ,,edition4 ,,published ,,by ,,bland ,,long1 ,,opticians1 ,,and ,,photographic ,,instrument ,,makers ,,to ,,her ,,majesty1 ,illustration ,,by ,,appointment4 #aec1 ,,fleet ,,street1 ,,london4 ,,entered ,,at ,,stationers' ,,hall1 ,price #as4 ,per ,post #as4 #a;d4 #aheh4 ,h4 ,,silverlock1 ,,printer1 ,,wardrobe ,,terrace1 ,,doctors' ,,commons1 ,,london1 ,e4,c4 ,,preface ,,to ,,first ,,edition4 ,the following pages shall be devoted to the description of a process on ,dry ,collodion1 which ,i believe to be at once simple and effective4 ,the experiments connected with the perfection of this process have occupied my leisure time for the space of two years or more1 and have been conducted with all the care of which ,i was master4 ,the constant repetition of them enables me to say1 that whoever will follow diligently the process step by step1 as detailed in this ,pamphlet1 must succeed in producing pictures in every way such as could be required by the most exacting critic4 ,the process is simple1 clean1 and expeditious2 and the resulting ,negatives possess the exquisite softness of ,albumen1 the brilliancy of the wet ,collodion1 and the fine artistic texture of the ,paper process4 ,to disarm criticism1 and to make peace with my fellow labourers in the art1 ,i wish it to be understood that ,i do not claim the use of ,collodion1 of ,gelatine1 of ,metagelatine1 or of any of the ,chemicals used in the process--most of these have been employed by others in various ways2 ,i merely reserve to myself the pleasure of placing in the hands of ,photographers a definite and simple plan by which pictures may be taken on ,dry ,collodion4 ,,charles ,a4 ,,long4 ,june #bj1 #aheg4 ,,preface ,,to ,,second ,,edition4 ,in issuing a second edition of the ,dry ,collodion process1 ,i would take occasion to remark1 that after some months' practical working1 it has not been found necessary to make any material alteration in the process2 success has usually attended the adoption of it1 and in those cases where good pictures have not resulted1 the failure has always been traced to the use of a ,collodion not suited to the process4 ,i cannot allow this opportunity to pass1 without thanking those gentlemen whose opinions possess weight in matters photographic1 for the very candid manner in which they have tested the capabilities of my process1 and for the very flattering testimony they have borne to its efficiency1 simplicity1 and certainty4 ,,charles ,a4 ,,long4 #aec1 ,fleet ,street1 ,september #aheg4 ,,preface ,,to ,,third ,,edition4 ,the process described in the following pages has now been in use for twelve months1 and ,i have much satisfaction in stating that it has1 in almost every instance where it has been adopted and carried out with care and attention1 yielded results which leave scarcely anything to be desired4 ,the present ,edition might more properly be termed a reprint1 as the alterations in the text do not extend to more than a few matters of detail1 which experience has shewn to be desirable1 the principles of the process remaining undisturbed4 ,,charles ,a4 ,,long4 #aec1 ,fleet ,street1 ,june #aheh4 ,,opinions ,,of ,,the ,,press4 ,from the ,athenum4 ,we have not merely examined the description given by ,mr4 ,long of his dry collodion process1 but we have witnessed the results obtained by following carefully his directions4 ,it appears to us that1 by it1 a collodion plate may be prepared at home1 wrapped in paper1 and packed in portmanteau2 that we may journey to ,rome or ,venice1 then place our plate in the camera obscura1 and allow it for a few minutes to receive the luminous image2 remove it in a dark room2 re-pack it and trouble ourselves no more about it until our return to ,england2 when1 in the room in which it was prepared1 we may witness the magic process of development1 and rejoice that we have1 without much labour1 secured a picture of the ,coliseum or of the ,bridge of ,sighs4 ,from the ,journal of the ,cambrian ,archological ,association4 ,new ,photographic ,process4--,mr4 ,long1 of the firm of ,bland and ,long1 ,opticians1 ,fleet ,street1 has recently put forth a valuable pamphlet1 in the form of an essay on the dry collodion process4 ,by means of this1 plates prepared weeks beforehand may be exposed to objects1 and then kept for weeks afterwards before they are developed1 as he has proved it himself on the ,continent4 ,the advantage of this process to travellers1 and especially to archologists1 is immense2 because hitherto the main drawback upon photography has been the trouble and expense of carrying chemicals1 tents1 c4 c41 besides the camera1 with its lenses1 to the scene of operation4 ,now1 however1 it will be sufficient to carry merely the camera1 with a suitable supply of plates prepared according to this process4 ,the observer can then1 by merely exposing his plates1 with the proper precautions1 bag any number of views per diem1 and on his return home can develop them--or have them developed--at leisure4 ,if this process succeeds1 it will have the effect of splitting photography into two distinct branches--the sthetic1 and the practical4 ,the former will fall to the share of the intelligent observer1 the traveller1 the man of taste1 who will go and search for objects1 combine them1 or use them1 under the most favourable sthetic circumstances1 and then will carry them home to be handed over to the man of practice4 ,once in his hands1 nothing will remain but to manipulate the plates according to the rules of photographic science1 by means of all the best appliances that a well fitted laboratory can furnish4 ,one branch will feed the other4 ,one will be the department of observation1 of search1 of taste1 of beauty2 the other will be that of calm scientific development1 of improvement1 of preservation4 ,one man will be like the artist who paints2 the other like the artist who engraves4 ,one will be like the author1 the man who writes2 the other like the printer1 the man who perpetuates4 ,we recommend members to enquire carefully about this new process2 because if it becomes firmly established1 any archologist moving about the ,country may get views of churches1 castles1 cromlechs1 meini-hirion1 seals1 c4 c41 usque ad satietatum--we had almost said ad nauseam2 but that word can never be connected with archology6 ,the upshot of this is1--,read ,mr4 ,long's pamphlet1 and set up a portable camera with his prepared plates1 as we intend doing ourselves6 ,from the ,liverpool and ,manchester ,photographic ,journal4 ,we must advise all who are interested in dry processes to obtain ,mr4 ,long's clearly written pamphlet4 7,leader1 ,july #aeth1 #aheg47 ,extract from ,proceedings of ,charlton ,photographic ,society1 ,october #hth1 #aheg4 ,paper by ,mr4 ,hooper1--,on the results of his experience in the practice of several ,preservative ,processes4 ,i commenced experimenting on the process of ,mr4 ,long4 ,the success ,i have met with from the first has convinced me that that process will ere long be generally adopted3 the plates being easily and quickly prepared1 and keeping well1 is a great advantage4 ,extract from ,letter from ,g4 ,r4 ,smith1 ,esq41 to the ,editor of the ,london ,photographic ,journal1 ,sept #ba1 #aheg4 ,my tour of a fortnight's duration having ended1 ,i returned to ,london1 and began developing 7the dry plates74 ,to my great delight1 ,i found all ,mr4 ,long had said in favour of his process fully realized4 ,picture after picture 7,i took twenty-eight7 came out with great beauty1 and so far as the process is concerned1 ,i have not had a single failure4 ,mr4 ,long's ,dry ,collodion ,process4 ,letter from ,robert ,hunt1 ,esq41 ,f4,r4,s41 to the ,editor of the ,london ,photographic ,journal1 ,october1 #aheg4 #f1 ,green's ,row1 ,chelsea4 ,sir1--,it is due to ,mr4 ,long that ,i should state what my experience has been with his dry collodion plates1 and ,i feel much satisfaction in doing so1 being enabled fully to confirm all that ,mr4 ,smith has said respecting the dry plates prepared as he has described 7,photo4 ,journ4 ,sept4 #ba74 ,on the #bfth of ,august1 ,mr4 ,long1 at my request1 furnished me with some of his dry collodion plates4 ,absence from ,london1 and the press of official engagements1 prevented my trying any experiments with those plates until the #cjth of ,september4 ,although the weather was very unfavourable1 the result was superior to my expectations4 ,on the #gth of ,october1 at four in the afternoon1 when the sky was covered with clouds and the weather stormy1 ,i exposed a plate in the camera obscura for ten minutes to the dark brick building1 ,chelsea ,hospital4 ,i enclose you a positive print from the result of this experiment4 ,when we remember that the sensitive plate had been kept by me for a period of forty-two days1 and then exposed under very unfavourable circumstances1 ,i think you will admit that the result is satisfactory4 ,i should not content myself with this trial1 but that ,i am again compelled to leave ,london for a long period1 and ,i shall have no other opportunity of testing these plates for this year4 ,i feel convinced that the traveller might with perfect safety use plates which have been prepared for a month1 and thus relieve himself from much labour and frequent annoyance1 by the use of ,mr4 ,long's process4 ,robert ,hunt4 ,from the ,illustrated ,london ,news1 ,january #i1 #aheh4 ,it is but a few years since1 when we heard with surprise1 and some incredulity1 that light could be made to delineate images of external objects upon chemically prepared tablets placed in the camera obscura1--now photography stares us in the face at every corner1--that which was wonderful has become familiar1--that which was mysterious is singularly common4 ,in cities1 we see glass houses1 on at least one roof in every street1--in villages1 caravans1 with ,brown and ,jones1 photographers1 are regularly found1--on the hills we discover the tent1 and in the valleys the camera1--by the river-side there is the mysterious head hidden in the dark curtains of a dark box1--and upon the sea-shore the tripod-stand is securely fixed in the sands1 and a biped is evidently focusing for the next fine ocean wave1--the sketcher has fled to his own especial solitudes1 and the photographer has usurped his place4 ,it has been said of the most recent photographic processes1 as was well said of the octo-syllabic verse1 that it possesses unfortunate facilities4 ,this is true in many respects of the positive collodion process1 by which the myriads of sad reflections on humanity are perpetrated4 ,not so1 however1 is it with the negative process1 by which alone we can multiply the beautiful things which the solar pencil traces with such fidelity4 ,the labour attendant upon a photographic tour is great1 and real enthusiasm alone carries the amateur forward4 ,the camera obscura and the stand are a burden1 and with the tent and chemical box1 they become a real load4 ,then there is the uncertainty attendant upon the processes4 ,we deal with the nicest chemical adjustments4 ,the balance is arranged with caution for a certain set of conditions1--alter but one of these1 and all goes wrong4 ,we leave home in the morning1 we work in the dark all day1 and we return jaded at night1 to find we have obtained--nothing4 ,sensitive as the collodion process is1 and charming as are the results1 when all goes on successfully1 it has not hitherto been a process which can be practised out of doors1 without many extraordinary1 expensive1 and troublesome appliances4 ,it is1 therefore1 with very much satisfaction that we have watched the progress of the so-called dry collodion processes4 ,nearly all the processes that have been published1--the gelatine1--the oxymel1--the glycerine1 and others1--have much that is excellent in them2 but it appears to us that a dry collodion process devised by ,mr4 ,long1 of which he has recently published a description1 is more simple and effective than any other4 ,we have seen beautiful pictures obtained in ,belgium upon plates prepared in ,england1 and which plates were brought to this country again before the pictures were developed4 ,any man may1 previously to starting on his journey1 prepare1 or purchase prepared1 a stock of glass plates4 ,armed with these and his camera1 he may proceed to ,where the bleak ,swiss their stormy mansion tread4 ,and force a churlish soil for scanty bread2 or to that ------sea ,cybele fresh from ocean ,rising with her tiara of proud towers1-- and1 resting on his way1 he may adjust his camera and his plate1 and in the few minutes which1 under any circumstances1 he would spend in observation1 he secures a picture for future study1--a photograph to give him pleasure in the quiet of his home4 ,mr4 ,long has published a little treatise1 with which we head this article1 and by following out the simple directions which he gives1 all may succeed in obtaining the important desideratum1--a parcel of highly sensitive plates1 which can be packed in paper and stowed away in a portmanteau1 to be drawn out as occasion may require1 to be returned again to the same package 7without having any of the annoyances attendant upon a box of liquid chemicals71 and a plate which can be kept with its dormant picture quite uninjured until the photographer1 on his arrival home1 at his perfect leisure1 in his own operating room1 can develop the photograph which he has obtained4 ,such are the facilities offered by this improvement1 that we may expect almost every traveller will avail himself of it1 and thus secure for his own portfolio1 and the portfolios of his friends1 views of scenes hallowed by their historical association1--of ruins rendered sacred from the sacred memories which still wrap them in their shadows1 as the mantling ivy clothes their crumbling walls4 ,,the ,,dry ,,collodion ,,process4 ,before describing in detail the manipulations of the process on ,dry ,collodion plates1 it will be necessary to say a few words on the materials and apparatus to be employed1 and also to give an account of the means of preparing the various solutions used in the process4 ,first1 ,,the ,,collodion4 ,this being the principal material we have to use1 we must exercise great care in the selection of a sample that possesses all the characteristics which fit it for a dry process4 ,we must reject all samples that possess great tenacity and contractile power3 the ,collodion must not be too thick1 and it must flow evenly over the plate1 and not set in ridges4 ,the best condition for the ,iodized ,collodion is that known as powdery1 that is1 being spread on the plate and partially dry1 it cannot be removed as a film1 but crumbles up on being pressed by the finger in its passage across the plate2 in fact1 such a condition as would arise from using gun cotton prepared with acids at a high temperature4 ,the following formula will be found to answer most admirably3 ,gun ,cotton #fj grains4 ,absolute ,alcohol #e ounces4 ,sulphuric ther1 sp4 gr4 #gcj #ae ounces4 ,the cotton is to be shaken up with the mixture of alcohol and ther1 and when dissolved1 the bottle containing it must be stood aside1 in order that any undissolved particles of cotton may subside4 ,the clear liquid may then be decanted into a clean bottle for use4 ,it will be as well to test the quality of the ,collodion thus prepared before coating any number of plates with it1 for1 although the above proportions are very excellent1 some little latitude must be allowed for the different degrees of solubility of the various samples of cotton used from time to time4 ,the film1 when spread1 on the glass plate and partially dry1 should not be capable of being removed in the form of a skin1 but should give before the finger and crumble up on its being rubbed across the plate4 ,should any difficulty1 however1 occur1 it would be better to obtain a sample of the ,collodion made by an experienced hand1 in order that a fair trial may be given to the process4 ,if the ,collodion be too contractile it will give rise to blisters in the film1 and will wash off the plate during development4 ,the ,iodizing ,solution that ,i have found to give the best results in this process is made in the manner following3-- ,absolute ,alcohol #h ounces4 ,iodide of ,cadmium #fd grains4 ,iodide of ,ammonium #fd grains4 ,the iodides are to be dissolved by agitation in the alcohol1 and the resulting solution is to be carefully filtered1 and preserved in a well stoppered bottle4 ,the ,iodized ,collodion consists of-- ,iodizing ,solution #b drams #a ounce ,plain ,collodion #f drams ,the ,collodion should always be iodized at least twelve hours before it is required2 this interval allows any insoluble matters either from the iodizing solution or from the ,collodion itself to fall to the bottom1 and enables the operator to pour off the clear solution into a perfectly clean bottle for use4 ,next in importance to the ,iodized ,collodion comes ,,the ,,preservative ,,solution4 ,some care is required in the preparation of this solution1 in order that it may be clear and bright when finished1 and not contain particles that would be deposited in its passage over the ,collodion film when being used4 ,the chief precaution to be observed is not to allow it to boil too rapidly1 and not to conduct the operation over too fierce a fire2 attention to this will prevent many failures1 and ensure a solution in every way suited for the process4 ,take one ounce of the best transparent gelatine1 and throw it into a pipkin in which has been previously placed one pint of distilled water2 set this on a slow fire1 or over a lamp1 until the gelatine is completely melted2 then weigh out half ounce of pure citric acid and dissolve it in two ounces of distilled water2 add this to the solution of gelatine1 stirring it during the addition with a glass rod4 ,the solution in the pipkin is now to be gently boiled for about half an hour3 remove it from the fire1 and add sufficient distilled water to make up the bulk of liquid to one pint4 ,when quite cold1 the liquid in the pipkin is to be filtered through two thicknesses of pure white blotting paper into a bottle perfectly dry and clean4 ,we now add to every pint of filtered preservative solution1 two ounces of alcohol of the specific gravity of #hdj4 ,the solution thus prepared is ready for use1 and should be of a pale amber colour1 without any signs of insoluble particles floating in it2 should any appear after it has been prepared for some days1 a second filtration will remove them1 and render the liquid again bright and clear4 ,it will be found better to prepare this solution only in the quantity indicated above1 unless the consumption be large1 for1 although it will keep good for a month or more1 my experience points to the fact1 that the most successful results follow the use of ,preservative ,solution freshly prepared4 ,,the ,,nitrate ,,of ,,silver ,,bath4 ,the bath for rendering the plates sensitive does not differ from that recommended for taking negatives with wet ,collodion4 ,the formula for its preparation may not be out of place1 however1 and may assist those whose knowledge of the matter is not perfect4 ,nitrate of ,silver 7fused7 #a ounces4 ,distilled ,water #a pint4 ,iodide of ,cadmium #c grains4 ,dissolve the nitrate of silver in half the water and then add the iodide of cadmium2 thoroughly agitate the mixture for five or ten minutes1 then add ounce of alcohol1 sp4 gr4 #hdj1 and fill up with the remaining half of the distilled water2 further agitation1 and subsequent filtration through two thicknesses of white bibulous paper1 will put us in possession of a negative bath4 ,the nitrate of silver being fused1 and consequently1 pure and neutral1 and as it is essential to obtain clean pictures that the bath should be slightly acid in its reaction1 we find it necessary to add #e or #f minims or drops of pure glacial acetic acid to a bath of #bj ounces1 in order that the above condition may obtain4 ,,the ,,developing ,,solution ,is very simple in its nature1 being merely a saturated solution of gallic acid in distilled water1 to which has been added a small proportion of alcohol of sp4 gr4 #hdj4 ,the exact formula is as follows3-- ,distilled ,water #a pint4 ,alcohol sp4 gr4 #hdj #a ounce4 ,gallic ,acid ounce4 ,the gallic acid will not be entirely dissolved1 but that left at the bottom of the bottle will ensure the solution being saturated2 it is better not to filter the developing solution until it is required for use1 as it is preferable to allow it to stand over an excess of gallic acid1 than for it to be withdrawn after a slight agitation with the crystals2 it is a great error to suppose that we obtain a saturated solution of gallic acid by merely agitating the crystals with water for a few moments4 ,the developing solution prepared as above directed will keep good and in working order for some weeks1 but when it becomes of a dark color1 it would be safer to reject it and prepare a fresh quantity than to run the risk of a failure from an impure and imperfect developing agent4 ,,nitrate ,,of ,,silver ,,solution1 ,for adding to the gallic acid during development1 is composed of ,fused ,nitrate of ,silver #cj grains4 ,distilled ,water #a ounce4 ,,the ,,fixing ,,solution ,consists of a solution of hyposulphite of soda in water1 7filtered17 in the following proportion3-- ,hyposulphite of ,soda in crystals #h ounces4 ,rain or ,filtered ,water #a pint4 ,the ,apparatus1 c4 required in the ,dry ,collodion process is of the most simple kind1 and consist of the following items ,glass plates4 ,pneumatic plate holders4 ,plate holder1 for cleaning the plates4 ,glass or porcelain dishes4 ,glass or gutta percha dipping bath and dipper4 ,silver hook1 for lifting plates4 ,levelling stand4 ,measures1 #a1 #b1 and #d ounce4 ,glass funnels4 ,wash leather4 ,some clean cloths and broad camel's hair brush4 ,cotton wool4 ,bibulous paper4 ,a ,the ,chemicals are-- ,nitrate of silver 7fused47 ,glacial acetic acid4 ,iodized ,collodion 7dry47 ,gelatine4 ,citric ,acid4 ,alcohol4 ,sulphuric ther4 ,gallic acid4 ,hyposulphite of soda4 ,iodide of cadmium4 ,benzoin varnish4 ,a ,the dry ,collodion and the various solutions1 ready for use1 may be obtained of the ,publishers4 ,in the above ,list we presume that the operator is in possession of a suitable camera and lens1 and the usual adjuncts of camera tripod1 c4 c4 ,these should all be of the best kind1 otherwise it will be impossible to obtain good results4 ,illustration ,,the ,,manipulation4 ,the process of obtaining a picture on ,dry ,collodion plates is in itself a most simple and easy matter1 but there are one or two precautions that appear necessary to ensure success that cannot be lightly neglected4 ,in the first place1 it is absolutely certain1 that if we want a clean and bright picture1 we must have a plate perfectly free from all extraneous matters1 such as soap1 grease1 c4 ,various plans for cleaning the glass plate have been proposed1 all more or less successful1 but in most of them there is one great fault1 namely1 that of using a powder1 as tripoli1 rotten-stone1 c4 to rub off the dirt with4 ,now we find that in practice this will not answer1 from the almost impossibility of getting rid of the floating particles of the powder when the plate is rendered slightly electrical by rubbing1 and as each of these particles if it become enveloped in the ,collodion film1 would produce a spot on the finished picture1 we find it necessary to search in another direction for a detergent for the glass plate to which this objection would not apply4 ,one soon presents itself in the form of old waste ,collodion--this spread on the glass plate and rubbed off again with cotton wool1 makes the best and most perfect cleanser hitherto proposed1 without any of the objections usually appended to other materials used for the same purpose4 ,the next precaution necessary to be observed is1 that all the solutions should be perfectly bright and clear2 they should be absolutely free from floating particles of any kind4 ,this is essential1 as it is impossible to obtain clean pictures without attention to it2 the floating bodies in the solution settle on the plate1 and form so many nuclei1 around which1 in the development of the picture1 the silver is deposited in an opaque mass1 forming spots and blemishes on the surface of the plate4 ,there is one precaution that cannot be dispensed with1 and that is1 to be sure that the chemicals employed are of absolute purity2 without this1 success is very problematical1 and vexation and disgust the sure reward of its neglect4 ,the process may for convenience be divided into the following stages3-- #a4--;,cleaning the plate4 #b4--;,coating it with ,collodion4 #c4--,rendering the plate sensitive4 #d4--;,applying the ,preservative solution4 #e4--;,exposure in the camera4 #f4--;,development of the picture4 #g4--;,fixing the developed image4 #h4--,varnishing the finished negative4 ,,cleaning ,,the ,,plate4 ,illustration3 ,fig4 #a4 ,the glass plate is first to be thoroughly washed with an abundance of water1 and dried on clean cloths2 it is then to be placed in the plate holder 7,fig4 #a71 and have poured over its upper side a small quantity of old ,collodion4 ,now take a tuft of cotton wool and rub the ,collodion all over the plate1 giving the hand a circular motion at the time3 keep rubbing until the ,collodion is very nearly dry1 then turn the plate in the holder and repeat the same treatment with the opposite side2 then lean the plate thus treated against a wall1 while another1 or any number are put through this stage4 ,when a sufficient number have been so far cleaned1 the plate holder is to be carefully wiped1 and the first plate--the edges of which have also been carefully wiped with a clean cloth--is to be replaced1 and treated with a smart rubbing with a wash leather1 the operator at intervals gently breathing on the plate4 ,both sides of the plate being cleaned in this way1 it may be removed1 after again wiping the edges carefully1 to the plate box1 to await the subsequent steps of the process4 ,plates cleaned in this manner should look perfectly transparent1 and free from any marks of the cloth or leather1 and when breathed upon should condense the moisture of the breath in one uniform degree over the whole surface4 ,if patches of uneven condensation appear1 a repetition of the process must be had recourse to4 ,the plate being clean1 we proceed to the next step1 ,,coating ,,the ,,plate4 ,lay a piece of clean blotting paper on the table1 larger than the plate we are about to use2 place the clean plate on this1 and then bring the pneumatic plate holder to bear on the centre of the glass1 making sure that it has laid hold firmly4 ,we then raise the plate with the left hand1 and bring the surface upwards which was previously on the blotting paper2 it will no doubt be found that small particles of dust have attached themselves to the plate1 these must be removed by a broad and soft camel's hair brush1 kept for this purpose only4 ,illustration3 ,fig4 #b4 ,the ,collodion is then to be poured on1 as shown in the diagram 7,fig4 #b71 and the superfluous quantity returned to the bottle from one of the corners of the plate4 ,it does not matter which of the corners is used for this purpose1 that which is most convenient to the operator assuming the preference4 ,if the ,collodion should have a tendency to set in ridges across the plate1 a rocking motion1 while the delivery corner is in the mouth of the bottle1 may be given to it1 still keeping the plate in a vertical plane4 ,this will restore the film to perfect evenness and freedom from irregularity of any sort4 ,the plate should be held in the vertical position for a few moments before being placed on the dipper to undergo the next operation of ,,rendering ,,the ,,plate ,,sensitive4 ,illustration3 ,fig4 #c4 ,the plate being placed1 coated side outwards1 on the dipper1 is to be plunged without hesitation into the nitrate of silver bath 7,fig4 #c74 ,this must be done without stopping1 otherwise a line across the plate will indicate1 on development1 the position of the plate in the bath at the time this stoppage took place2 so that if we were to immerse the plate by a series of jerks1 we should have as a result1 so many bands of unequal development in the finished picture2 showing the importance of plunging the plate into the bath without any stoppage during its descent4 ,illustration3 ,fig4 #d4 ,when the plate has rested for half a minute in the bath1 it may be withdrawn1 and quickly re-immersed4 ,this washing must be continued at intervals1 until the greasy appearance goes off1 generally for the space of two minutes1 when the plate is to be taken out of the bath and placed with its lower edge on a pad of blotting paper1 in a position as shown in the cut 7,fig4 #d47 ,a fragment of blotting paper is then to be used to absorb the moisture from the back of the plate1 and a pneumatic plate holder--which should only be used for this purpose--is applied to it to form a support while ,,applying ,,the ,,preservative ,,solution4 ,illustration3 ,fig4 #e4 ,taking the plate in the left hand by means of the pneumatic holder1 incline it as shown in the diagram 7,fig4 #e72 then having poured into a perfectly clean measure rather more of the preservative solution than is necessary to cover the plate twice1,b pour half of it along the upper edge 7,a ,b7 in such a manner1 that a wave of the solution may flow uniformly from one end of the plate to the other2 allow this to flow off into the waste pan or sink1 and then bring the plate to the horizontal position1 and pour on the remainder of the preservative solution1 eight times at least1 allowing it to flow back into the measure from each corner in succession1 in order that the whole plate may be brought uniformly under its influence4 ,the plate is to be again placed on a piece of clean blotting paper 7as shown at ,fig4 #d71 and its back once more wiped with a fragment of blotting or papier ,joseph1 in order to remove any of the preservative solution that may have run from the surface to the underside in the previous operation4 ,the plate thus preserved is to be reared on a piece of blotting paper with its face against the wall until dry1 and is then to be stowed away in a plate box1 perfectly light-tight to await the ,b ,a plate1 #i inches by #g1 takes about #a ounce of solution4 ,,exposure ,,in ,,the ,,camera4 ,collodion plates preserved as above directed1 will keep perfectly good and sensitive for #ab months at least2 and from the appearance of the developed image on a plate that has been kept that time1 ,i see at present no reason why1 if preserved from the damp1 they would not keep indefinitely4 ,in my experiments1 ,i have never found the least difference in sensitiveness1 whether the plate be used within a few hours of the time of its preparation1 or has been kept for months2 until1 however1 we have had more experience in the matter1 it would be safer not to rely on plates more than #ab months old4 ,the time of exposure in the camera1 of course varies in this process1 under the same circumstances as it does with the wet ,collodion2 but ,i have found as a general rule1 that it is better to give the plate a full exposure than to fall into the opposite extreme3 that is to say1 it is preferable to expose the plate sufficient time for the deepest shadows to make an impression than to close the dark slide at an earlier period1 the mode of development allowing considerable latitude in this particular4 ,with a #c-;inch single lens1 #af-;inch focus1 with a -inch stop1 the usual time for a bright landscape will be about #e minutes2 this of course is merely an approximation to the time of exposure1 the exact time can only be arrived at by experience4 ,i do not think ,i can do better than follow the plan adopted in my ,practical ,photography1 of giving instances of under and over exposure1 as a means of educating the tyro in the appearances that result from these conditions of the plate4 ,if the exposure has been of too short duration1 the image will come out under the developing solution with difficulty2 and after a continued immersion in it will only present the high lights1 the deep shadows not being represented1 or1 if so1 in so faint a manner as to be useless in the picture4 ,an over exposed plate1 when treated with the developing solution1 will almost immediately give indications of the picture2 and in a few minutes1 the whole of the picture1 deep shadows and all1 will come put in unnatural force2 on looking through the picture thus produced1 we shall observe a great flatness in it1 there is a want of contrast between the various parts1 and although by continuing the development we might obtain a tolerably intense negative1 the resulting picture would be flat1 meagre1 and unsatisfactory3 on the contrary1 a plate that has been exposed for the correct time1 will comport itself very differently under development from the foregoing4 ,the sky and high lights will first appear1 then the half tones1 and lastly1 the parts of the picture that were in deep shadow will show themselves2 this effect should take place in about five minutes from the time of immersion in the developing bath3 a picture that comes out sooner than this1 is1 as a general rule1 over exposed2 and one that is much after the five minutes before it makes its appearance1 may be considered as under exposed4 ,we trust that the above instances may be of service in indicating the average time required for an exposure of the plate1 but we must ask the reader not to take the figures given as actual values1 but merely as very close approximations to the truth4 ,we will imagine the plate to have been properly exposed1 and proceed to ,,the ,,development ,,of ,,the ,,picture4 ,it is not necessary that the picture should be developed immediately after exposure in the camera2 any time that is convenient to the operator may intervene between the processes1 provided the aggregate time before and after exposure does not exceed the limits of keeping power of the plate4 ,the development of the picture may be conducted in two ways1 either by immersing the plate in baths or dishes1 or by placing it on the levelling stand and treating it with the solutions1 in their proper order1 as detailed below4 ,each plan possesses certain advantages1 but it is of little consequence which one is followed4 ,perhaps there is less danger of the film washing off if the plate be treated on the levelling stand1 and on the other side with large plates it is more difficult to cover them evenly with the developing solution than it is simply to immerse them in a pan of solution4 ,we say to the reader1 try both ways1 and make your own selection4 ,the plate upon being removed from the camera is placed face upwards in a porcelain or glass dish of a convenient size 7not too large71 and sufficient distilled water is to be poured over it to cover the surface thoroughly--this is for the purpose of softening the preservative solution1 and must be allowed to remain on the plate for five minutes2 the plate is then to be lifted in and out of the water by means of the silver hook4 ,this done1 remove the plate to a perfectly clean dish1 and pour carefully over it the developing solution1 composed of ,saturated ,solution of ,gallic ,acid 7p4 #aj7 #h ounces4 ,solution of ,nitrate of ,silver 7p4 #aj7 #b drams4 ,,thoroughly ,,mixed4 ,in a few minutes the picture will begin to make its appearance1 and will gradually unfold its details under the influence of the developer1 until the whole of them are apparent2 on raising the plate1 however1 when this stage of development is reached1 and viewing it by transmitted light1 the picture will appear weak and poor2 we must now remove the plate from the bath1 and add #b drams more of the nitrate silver solution1 and having thoroughly mixed it with the gallic acid already in the dish1 we return the partially developed plate1 which in the course of a few minutes will have acquired a great amount of intensity1--the exact degree can be regulated by the time of immersion3 when the picture appears sufficiently intense1 it is to be removed from the developing dish1 and a gentle stream of water is poured over it1 in order to remove any adhering developing solution1 and stop all further reducing action on it4 ,during the whole time of the development1 the gallic acid should remain quite clear2 it will become slightly discoloured before the end of the development1 but it ought not at any time to become muddy1 or it will deposit a sort of sandy sediment on the surface of the plate1 which cannot be removed by subsequent washing4 ,the usual time occupied in the development of a successful picture is from #bj to #cj minutes1 it might be developed much quicker by using pyrogallic acid1 but at present ,i give the preference to the developer ,i have described1 as ,i believe it to be more certain1 and more under the control of the operator than the pyrogallic acid2 and further1 as it is not necessary to watch the development all the time it is going on1 there can be very little saving of time in the more rapid method of bringing out the latent picture4 ,the picture being washed free from the adhering developing solution1 is to be placed on the levelling stand1 and subjected to the seventh part of the process-- ,,fixing ,,the ,,developed ,,image4 ,this is accomplished by pouring over the surface of the plate sufficient solution of hyposulphite of soda 7p4 #ae7 to thoroughly cover it1 this will dissolve out the unaltered iodide of silver1 and give us a clear and bright picture1 in which the deep shadows should be as transparent as the glass itself1 and the high lights as dense as a piece of metal1 the intermediate tones assuming their proper positions according to the intensity of the light that was concerned in their formation4 ,when the whole of the yellow iodide of silver is removed1 the fixing solution may be thrown off1 and the plate must be treated with an abundance of water2 too much cannot well be given at this stage1 as the hyposulphite adheres with great tenacity to the plate1 even after a good washing4 ,the back of the plate must be washed as well as the front1 for ,i have found that a neglect of this precaution has ruined many a fine negative2 the hyposulphite remaining at the back finding its way by capillary attraction to the surface1 and once there1 its destructive qualities are sure1 sooner or later1 to render themselves evident4 ,the picture being thoroughly washed1 and either dried spontaneously or by the fire1 has only to be covered with a film of varnish4 ,and now comes the last operation1 of ,,varnishing ,,the ,,finished ,,negative4 ,benzoin varnish is the best coating that can be given to a ,collodion negative4 ,it resists the action of pieces of grit2 it does not crack2 and1 above all1 it does not1 like amber varnish1 split off the picture on the slightest friction4 ,the application of this varnish is a very simple matter4 ,the negative is to be again placed on a pneumatic plate holder1 and the varnish is to be poured on to the surface in precisely the same manner as the ,collodion was at the commencement of the process1 the superfluous quantity being returned to the bottle3 in a few moments the varnish will be quite dry and hard1 and the plate may be handled with perfect safety4 ,i may mention1 as a precaution1 in varnishing the plate1 that it is better to perform that operation in a still atmosphere2 as the solvent of the gum being chloroform and very volatile1 if it were conducted in a current of air1 there might be some difficulty in obtaining an even coating to the picture4 ,in concluding this description of a process1 which is at once simple and certain1 ,i would ask the patient attention of those who may do me the honor of repeating my experiments4 ,i have endeavoured to render the details of the process as intelligible as possible1 and if ,i have succeeded in advancing the art of ,photography only one step by so doing1 ,i consider that it is an ample return for hours and days spent in anxious thought and laborious experiment4 ,,finis4 ,,special ,,list ,,of ,,requisites ,,for ,,the ,,dry ,,collodion ,,process1 ,,supplied ,,by ,messrs1 ,,bland ,,long1 ,opticians1 ,photographic ,instrument ,makers ,,to ,,the ,,queen1 #aec1 ,,fleet ,,street1 ,,london4 99 99 99 99 99 ,,bland ,,long',s ,,iodized ,,dry ,,collodion4 ,this preparation will keep for an indefinite period1 and can be exported to any climate1 without risk of deterioration4 ,half-pints1 #ajs42 ,pints1 #ahs4 99 99 99 99 99 ,,bland ,,long',s ,,preservative ,,solution1 ,,ready ,,for ,,use4--#as4 per pint4 ,,bland ,,long',s ,,benzoin ,,varnish1 ,,for ,,protecting ,,the ,,finished ,,negative4 #as4 per oz4 ,this varnish does not require the plate to be warmed2 but dries instantly1 leaving a perfectly hard transparent coating on the picture4 99 99 99 99 99 ,,nitrate ,,of ,,silver ,,bath1 ,,for ,,bland ,,long',s ,,dry ,,collodion1 ,ready for immediate use4--#gs4 #f;d4 per pint4 99 99 99 99 99 ,,pure ,,chemicals4 s4 d4 ,fused ,nitrate of ,silver1 absolutely pure #d #f per oz4 ,glacial ,acetic ,acid #a #j ,pure ,gelatine #j #f ,pure ,citric ,acid #j #f ,gallic ,acid1 pure #a #f ,iodide of ,cadmium #c #j ,hyposulphite of ,soda #a #j per lb4 ,pure ,sulphuric ther #j #f per oz4 ,absolute ,alcohol #j #f 99 99 99 99 99 ,,for ,,the ,,prices ,,of ,,apparatus ,,see ,,bland ,,long',s ,illustrated ,catalogue of ,photographic ,apparatus ,sent free by post1 on application4 ,,sensitive ,,dry ,,collodion ,,plates1 ,,ready ,,for ,,exposure ,,in ,,the ,,camera4 7,,long',s ,,process47 99 99 99 99 99 ,messrs4 ,bland ,long are now prepared to supply these plates1 carefully secured in sealed cases1 with full directions for exposure and development1 of all sizes and in any quantity1 at the following prices3-- ,per ,doz4 ,per ,doz4 s4 d4 4 s4 d4 #d #c #e #j #g #f #j #ad #j #e #d #f #f #h #f #j #ah #j #e #c #f #j #i #g #a #a #j #f #c #h #f #aj #h #a #f #j #f #d #h #f #aa #i #a #ac #f #f #c #h #i #ab #aj #b #j #j #f #e #h #f #ae #ab #d #j #j ,,larger ,,or ,,other ,,sizes ,,to ,,order4 ,the advantages of a certain and simple ,dry ,collodion ,process are so obvious to those who have practised ,photography in the open air1 that we feel it is merely necessary to introduce the above list to their notice with as few remarks as possible4 ,we would1 however1 mention a few particulars connected with the process for the information of those who have not hitherto practised the ,dry ,collodion process1 as detailed by ,mr4 ,long4 ,the plates as prepared for sale1 are hermetically sealed in an envelope perfectly impervious to air and moisture1 they can therefore be exported to any climate without risk of deterioration4 ,plates prepared by ,mr4 ,long's process will keep sensitive for almost an indefinite period1 and can be developed at any time without regard to the date of exposure2 this1 it will be seen1 is of immense advantage to the tourist1 as he can delay the development of the whole of his plates until his return4 ,to those ,photographers whose inclinations or want of leisure will not admit of their carrying through the first preparation of the plate1 these ,dry ,sensitive ,plates will be found invaluable1 enabling their whole energy to be directed to the more careful selection of subject4 ,the plates being dry1 there is no danger of dust settling on their surfaces2 this point will be appreciated by every ,photographer4 ,the development of the pictures can be conducted in any room whence the light can be excluded--as the process is simple and clean--three dishes being the only requisites in point of apparatus4 ,to ,officers1 ,engineers1 and ,architects1 these ,dry ,plates offer a desideratum of no small value1 as they are always ready for use1 occupy very little room in travelling1 and can be used under circumstances which would preclude the adoption of any process that had to be carried out on the spot4 99 99 99 99 99 ,,bland ,,long1 ,photographic ,instrument ,makers to the ,queen #aec1 ,,fleet ,,street1 ,,london4 ,,the ,,dry ,,collodion ,,processes4 99 99 99 99 99 ,messrs4 ,,bland ,,long have invented the following simple means of ,,changing ,,the ,,dry ,,collodion ,,plates while working in the fields4 ,the plan has been in use for some time1 and answers perfectly4 99 99 99 99 99 ,price according to size4 ,adapted to ,stereoscopic ,camera1 #aes4 99 99 99 99 99 ,illustration ,,description ,,and ,,directions ,,for ,,use4 ,no matter what process we employ to retain the sensitiveness of our plates1 it is most objectionable that the glasses should be made to slide by their gravity from the plate-box to the slide2 for if we employ either honey1 glycerine1 or oxymel as preservative agents1 the chances are considerably in favor of an amount of dust settling on the surface1 the dust being in a great part formed by the attrition of the roughened edges of the plate against the plate-box4 ,another inconvenience attending the use of a box when the plate has to slide1 is the danger that exists under that arrangement of ripping the film from the edges of the plate by the friction against the groove in the box which holds it4 ,these may appear very trivial matters1 but they are nevertheless great drawbacks to successful operations4 ,we may mention that the plan we are about to describe is equally applicable to all ,cameras of moderate size4 ,we will1 however1 take our description from the form of apparatus adapted to a double lens ,stereoscopic ,camera4 ,the ,camera 7,a7 is furnished at its back with two wires 7,b74 ,on these wires slides the plate-box 7,c71 which has previously been fitted at its sides with two sockets 7,d74 ,just inside the back of the ,camera box is a spring 7,e71 and on the top of the ,camera is a button 7,f71 which secures the dark slide in its place4 ,we now slide the box of prepared plates 7,c7 on to the wires 7,b71 the lid of the box opening from the ,camera2 we then stretch over the whole affair1 the black light proof covering 7,g72 this completes the arrangement1 and now for the mode of operating4 ,the opaque covering is furnished at its side with two elastic rings4 ,into these thrust the hands1 so that the rings may firmly encompass the wrist4 ,then open the plate-box1 and throw the lid quite back4 ,next unbutton the door of the dark slide1 and raise it until the spring 7,e7 flies underneath it1 and retains it in a horizontal position4 ,this we will presume to be done with the right hand2 the left hand being engaged as soon as the door is opened1 in holding the plate that is already in the back in its place4 ,the right hand being now at liberty1 comes to the assistance of the left1 and the plate that has undergone exposure is safely transferred to the vacant groove in the plate-box4 ,this accomplished1 the next plate is to be placed in the back1 and the same operations gone through in the inverse order1 the left holding the plate in its place1 while the right releases the door from the influence of the spring 7,e71 and re-buttons it1 leaving the plate quite safe in the dark slide4 ,when we require to focus for a fresh picture1 it is only necessary to remove the dark covering from that part of the ,camera where the ground glass is placed4 ,the picture can be seen without removing the plate-box or the whole of the covering4 ,it is obvious that there is no limit to the number of glasses that can be taken to the field of operations4 ,in this way1 several boxes holding a dozen each1 can be strapped together and placed on the ,camera1 one by one1 as occasion or opportunity may direct4 99 99 99 99 99 ,h4 ,silverlock1 ,printer1 ,doctors' ,commons4 ,,practical ,,photography1 ,,on ,,glass ,,and ,,paper1 ,a ,manual1 ,,containing ,,simple ,,directions ,,for ,,the ,,production ,,of ,,portraits1 ,,views1 c4 ,,by ,,the ,,agency ,,of ,,light1 ,,including ,,the ,collodion1 ,albumen1 ,calotype1 ,waxed ,paper1 and ,positive ,paper ,processes4 ,by ,,charles ,a ,,long4 ,fourth ,edition1 price #as42 per ,post1 #as4 #b;d4 99 99 99 99 99 ,,illustrated ,,photographic ,,catalogue1 ,,free ,,by ,,post4 99 99 99 99 99 ,,spectacles3 ,,when ,,to ,,wear ,,and ,,how ,,to ,,use ,,them4 ,,addressed ,,to ,,those ,,who ,,value ,,their ,,sight4 ,by ,,charles ,a4 ,,long1 ,,third ,,edition4 ,,post ,,free1 ,,sixpence4 99 99 99 99 99 ,,also1 ,a ,,descriptive ,,and ,,general ,,catalogue ,,of ,,scientific ,,educational ,,instruments ,,and ,,chemical ,,preparations1 ,manufactured and ,sold by ,,bland ,,long1 ,,opticians1 ,,philosophical1 ,,photographical1 ,,and ,,chemical ,,instrument ,,makers1 ,,and ,,operative ,,chemists4 ,free by ,post4 ,,published ,,by ,,bland ,,long1 ,opticians1 ,philosophical and ,photographical ,instrument ,makers to the ,queen1 #afc1 ,,fleet ,,street4 99 99 99 99 99 ,transcriber ,note ,minor typos corrected4 ,images moved to prevent splitting paragraphs4