THE KEILEY GLYCERINE PROCESS. 



K. ROWA. 



Glycerine has long been used as a re- 

 strainer in connection with the develop- 

 ment of platinum prints. Till the introduc- 

 tion of Mr. Keiley's process it was used 

 in the developing solution to eliminate 

 delicate half tones by causing them to re- 

 sist the action of the developer ; thus giv- 

 ing clean, contrasting black and white prints 

 through the absence of the intervening half 

 tones. The glycerine acts as a restrainer. 

 The developer oxidizes the image on the 

 print. Wherever the image is strongly 

 oxidized the picture is correspondingly 

 dark or black. Where the image has not 

 been oxidized it is soluble in the acid clear- 

 ing bath and disappears when immersed 

 therein, leaving only clear paper in such 

 places. The glycerine process, as such, 

 came into being with the experiments of 

 Mr. Joseph T. Keiley, its inventor, and only 

 took its place among the advanced photo- 

 graphic processes of modern photography 

 with the publication of the results of his 

 experiments which were given to the world 

 in 1900. Later the full account of these 

 experiments and the process was published 

 in pamphlet form with explanations, and 

 illustrations. Copies of this pamphlet can 

 be secured from Tennant & Ward, 289 

 4th avenue, New York. 



Working on the essential principle in- 

 volved, Mr. Keiley elaborated a system and 

 process whereby it is not only possible to 

 eliminate half tones, but to correct or 

 modify full tones, to force half tones, to 

 introduce lights and shades, and even to 

 make outline sketches. In a word, with the 

 perfection of this process the development 

 of the platinum print and its various parts 

 was brought within the almost absolute 

 control of the manipulator. This was 

 made possible through the introduction of 

 blotters and brushes. 



An ounce or 2 of pure glycerine is placed 

 in a small jar or saucer, a half and half 

 solution of normal developer and glycerine 

 in a second, and a full strength solution 

 of normal developer in a third. Normal 

 developer, for the purposes of this article, 

 is the developer prepared according to the 

 Willis & Clements formula and the pre- 

 pared salts sold by them. The print, hav- 

 ing been printed rather deeper than for 

 ordinary development, or for the high 

 lights, sky, etc., is placed on a large plate 

 of sheet glass and brushed over with 

 glycerine with a broad brush. The 1^2 

 inch or 2 inch rubber-set, plate-dusting 

 camel's hair brushes are the best for the 

 purpose. Use them solely for this work. 

 Then the half and half solution is brushed 



over such parts of the print as are to be 

 developed, the other portions of the print 

 being meantime kept covered with glycer- 

 ine and free from developer. Where any 

 developer runs over these parts it should 

 at once be removed with blotting paper ex- 

 pressly prepared for photographic use. 

 Also the entire print should be blotted off 

 from time to time and recoated with 

 glycerine, to prevent the uneven gathering 

 of developer on its surface and consequent 

 uneven development. 



Where strong tones are required full 

 strength developer is carefully brushed on 

 such parts, which must be blotted off as 

 soon as the required depth has been ob- 

 tained. For fine work or outline sketches 

 a finely pointed Japanese drawing brush is 

 used. Outlining work is usually done with 

 full strength developer, the brush being 

 permitted to carry only enough developer 

 to moisten the line, but not enough to flow 

 over the print. In coating the print with 

 glycerine care must be taken to coat simply 

 and not to float the surface of the print. 

 Otherwise the developer will work its way 

 unevenly under the glycerine and develop- 

 ing unevenly will make unpleasant spots 

 or stains. 



When development is finished, the print 

 is immersed in the regular platinum clear- 

 ing acid bath, which is immediately brushed 

 over the surface of the print with one of 

 the rubber-set brushes used only for this 

 purpose. This is done to ensure the clear- 

 ing bath at once reaching the surface of the 

 print, as the glycerine acts as a shield and 

 the developer will often continue its action 

 under the surface of the glycerine while 

 actually in the acid bath, thus often spoil- 

 ing a carefully developed print. 



Should hair from the developing brushes 

 get on the surface of the print during the 

 course of development it should immedi- 

 ately be removed, as the developer will lie 

 along any hairs that are permitted to stay 

 any time and develop the lines thus made 

 on the face of the print. The print is 

 cleared, washed and dried in the ordinary 

 way. 



The illustration used with this article is 

 a half tone reproduction from some prints 

 made by Mr. Keiley from one of his land- 

 scape negatives and gives a fair idea of 

 the range of the process. The top picture 

 is from an unmanipulated or what is known 

 as a straight print. The three following 

 are brush developed glycerine prints. The 

 print for the second illustration was some- 

 what over printed. The dark portion of the 

 sky and tree line, and dark spots in fore- 



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