438 



NOTES AND QUERIES.^ 



[De( 



185c 



the spot where the plate is prepared. We are aware that 

 various means have been proposed to obviate this incon- 

 venience, such as tents, cameras with apparatus inside, 

 &c. ; all more or less inconvenient to the travelling pho- 

 tographer. It, therefore, is a matter of great and para- 

 mount importance, that we should be enabled to keep the 

 collodion film sensitive for some considerable time ; and 

 this I propose to accomplish in the manner following : — 

 The plate is to be coated in the usual manner with 

 iodized collodion, and rendered sensitive in the ordinary 

 way in the nitrate of silver bath. The time of immersion 

 I have found to answer best, is from three to four minutes, 

 at a temperature of 60° Fahi-. On removal of the plate 

 from the bath, it is to be allowed to drain from one corner 

 for the space of half a minute, and the surface is then to 

 be very quickly washed with distilled water. This is in 

 order to remove the film of nitrate of silver on the face of 

 the plate, which would otherwise interfere with the sub- 

 sequent pi'ocess. The plate thus washed, is to be placed 

 in a horizontal position on a table, or levelling stand, and 

 allowed to remain in that condition until the collodion 

 film is just surface dry. 



During the interval of the drying, prepare the following 

 solution : — Dissolve 40 grains of gutta percha, as pure as 

 it can be obtained, in one ounce of pure chloroform, place 

 the bottle in hot water, and when the gutta percha is dis- 

 solved, allow it to settle, and decant the clear liquid into 

 a perfectly dry bottle. 



The plate being by this time surface dry, hold it in the 

 same position as when pouring on the collodion, and 

 spread over its surface as quickly as possible the clear 

 solution of gutta percha, returning the superfluous quan- 

 tity to the bottle. When the plate has tolerably well 

 drained, tui-n it into a horizontal position once more, and 

 after waiting a few minutes (the exact time depending on 

 the temperature), it will be found coated with a trans- 

 parent tough skin of gutta percha. 



When quite set, which may be tested by the touch, 

 pour some of the solution of gutta percha into a shallow 

 porcelain or glass dish longer than the plate, and then dip 

 the edges of the plate successively into this to the depth of 

 one-eighth of an inch, keeping the plate in a vertical posi- 

 tion all the time ; by this means we thoroughly envelope 

 the sensitive film in a case of gutta percha, thereby pre- 

 venting the escape of the moisture contained in the collodion 

 film for an indefinite period. 



Having prepared our plate thus far, it can be stowed 

 away in a dark box to await the exposure in the camera. 



It will be obvious to most persons that the plate pre- 

 pared as above requires a little different treatment in the 

 camera, the only difference, however, being in the position 

 assigned to the sensitive surface, which in this case is 

 that next to the glass on which the film is spread ; the 

 glass side of the prepared plate is turned towards the 

 light, and after being exposed to the influence of the 

 actinic radiations for the requisite time, it is removed, 

 and subjected to the following operation, in order to de- 

 velope the latent image. 



Bj' means of a sharp penknife cut through the film of 

 gutta percha on the coated side of the glass, all round the 

 edges, and having previously wetted a square piece of 

 white blotting-paper, place it in contact with the film, 

 using a gentle pressure to make it adhere, in such a 

 manner, that one edge of the blotting-paper max come 

 within one-sixteenth of an inch of the top of the film ; 

 with great care this unoccupied one-sixteenth of film is 

 to be turned over the edge of the blotting-paper, and 

 there held by the thumb of each hand, one on either 

 corner ; then, by cautiously lifting the corner under each 

 thumb with the nail of the forefinger, at the same time 

 withdrawing the hands in the direction of the bottom of 

 No. 318.] 



the plate, we can easily strip off the whole of the film, 

 and have the surface exposed on which the light has been 

 allowed to act. 



The blotting-paper, with its adhering film upwards, is 

 then to be placed on a porcelain slab, which has been 

 previously wetted with distilled water, and the develop- 

 ing solution composed of p3'rogallic acid 1^ grains, acetic 

 acid J drachm, water 1 oz., is to be poured over it, and 

 manipulated in the same manner as if we were operating 

 with the ordhiary collodion film. 



When the picture is sufficiently developed, remove it, 

 still on the blotting-paper, to a bath of hyposulphate of 

 soda of the usual strength, and finally free from the 

 blotting-paper, to a capacious pan of clean water, where 

 it may be allowed to soak for some time, in order to free 

 it from any adhering hyposulphate. 



The picture thus produced is placed between folds of 

 blotting-paper, and dried spontaneously ; when dry it can 

 be printed from in the same manner as any other negative. 



The advantages attending this new process are obvious, 

 for by the envelope of gutta percha we entirely prevent 

 the evaporation of the moisture requisite for the sensi- 

 tiveness of the film, and are thereby enabled to keep the 

 plate for an indefinite period. 



Further, there is a vast advantage over other plans 

 which have been devised for the same purpose, namely, 

 that the film destined to receive the image is perfectly 

 protected from dust, one of the greatest enemies of the 

 photographer. 



Again, the proofs when finished are more easily stowed 

 away, and are not so readily damaged as when left on the 

 glass : in fact, when more practice has been bestowed on 

 the process than I have been yet enabled to give, I have 

 no doubt that it will be as easy to prepare plates of very 

 large dimensions, as it is at present those of small size, 

 and that the photographer will be in possession of a 

 means of perpetuating scenes which at present, owing to 

 the difficulties in out-door manipulation, are quite beyond 

 his reach. Charles A. Long. 



153. Fleet Street. 



Shakspere and Cervantes (Vol. xii., p. 399.). — 

 It is asserted that "Shakspeare and Cervantes 

 (two of the greatest contemporaries that ever 

 existed) died at the same hour, the former on his 

 own birth-day." 



I must beg leave to express my conviction, 

 1. That Shakspere and Cervantes did not die on 

 the same day; 2. That there is no evidence to 

 prove at what hour either of them died ; and 3. 

 That there is no evidence to prove on what day 

 Shakspere was born. I make only this skirmish- 

 ing reply, the statement in question being one of 

 those on which it is my design to organize assaults. 



Bolton Cobney. 



The De Witts (Vol. xii., pp. 69. 244. 310.). — 

 Hume says of Cornelius de Witt : 



"This man, who had bravely served his country in 

 war, and had been invested with the highest dignities, 

 was delivered into the hands of the executioner, and torn 

 in pieces by the most inhuman torments. Amidst the 

 severe agonies which he endured, he still made protesta- 

 tions of his innocence, and frequently repeated an ode of 



