1886.] 



MICROSCOPICAL JOUENAL. 



93 



expose as quick as possible. This 

 is for landscape work. For photo- 

 micrography do the same but give 

 longer exposures. On developing it 

 will be seen what part of the plate 

 is properly exposed. 



The composition of the develop- 

 ing solutions is given in formula i 

 below. 



Place the plate to be developed, film 

 side up, in the developing pan in the 

 dark room lighted with ruby or orange 

 light, and pour over it sufficient solu- 

 tion to cover it. Then keep up a 

 rocking motion, causing the devel- 

 oper to flow constantly over the plate. 

 In a few seconds the image wall ap- 

 pear, and gradually grow in strength. 

 Continue the operation until all the 

 details of the subject are visible on 

 the film side. This may require five 

 minutes or half an hour, according 

 to the exposure given. The beginner 

 w^ill find it difficult to tell when the 

 development is carried far enough. 

 In an ordinary landscape, watch the 

 shadows, which are the light parts on 

 the developing plate, and if there 

 are any details in the deep shadows 

 of the subject, continue the develop- 

 ment until they appear. If they do not 

 appearthe plate requires a longer ex- 

 posure in the camera. If they do 

 appear, remember in the subsequent 

 operations they will apparently lose 

 some of their strength, so do not 

 cease developing until they are dis- 

 tinctly brought out. The shadows 

 in deep-shaded foliage will sometimes 

 remain quite clear while the remain- 

 der of the picture is fully developed. 

 In such cases do not spoil the princi- 

 pal part of the picture for the sake 

 of the detail in the shadows. Judg- 

 ment must be used in this work, and 

 it will soon be discovered that when 

 a subject has strong contrasts of light 

 and shade, the light parts must be a 

 trifle over exposed to get detail in the 

 shadows. Such a subject requires 

 special work in the developing, which 

 will be subsequently considered. If, 

 instead of a landscape, the picture be 

 taken to portray a special object, a 



house, or a group of persons out of 

 doors, then the development must be 

 conducted with special reference to 

 the part of the picture desired, and 

 when the details of that part are 

 strong enough, the remainder of the 

 picture is w^orthy of only secondary 

 consideration. 



The detail in the shadow^s being 

 out, it then becomes necessary to 

 judge of the strength of the picture. . 

 This is done by looking through the 

 plate toward the ruby light. The 

 operator soon learns to judge of the 

 density in this way, but here the 

 thickness of the film must be taken 

 into account. When the film is thin 

 the picture may be developed until it 

 can be distinctly seen from the back 

 of the plate by reflected light. When 

 the film is quite thick it is more difii- 

 cult to judge concerning the density 

 of the image. It is not likely to de- 

 velop through the film so as to be 

 visible at the back, and the only in- 

 dication we can have is by looking 

 through it. The beginner is almost 

 sure to stop development of such a 

 plate too soon. A good rule with 

 thick films is to develop until one is 

 sure they are done, and then continue 

 the operation for sometime longer. 



When fully developed, remove the 

 plate from the tray, and place it under 

 the tap of running water for a few 

 moments, or in a tray of water to 

 wash ort' the developer. Then trans- 

 fer it to a tray containing a solution 

 of alum prepared according to form- 

 ula 8. The alum solution prevents the 

 irregular swelling up and loosening 

 of the film from the glass, which is 

 sometimes troublesome in warm 

 weather. It hardens the film and 

 makes it less subject to injury. In 

 five or ten minutes remove the plate 

 from the alum tray and wash it quite 

 thoroughly. 



Then place it in the hyposulphite 

 of soda fixing solution formula 9. 

 This solution dissolves all the silver 

 compounds in the film that have not 

 been changed by, and are still sensi- 

 tive to, light. All the white portions 



