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40 THE PHOTOGRAPHIC NEWS. [January 16, 1891. The plate is placed on the bottom of a glass dish, and the above mixture poured over it. It is allowed to act for about half a minute. Then, in a glass measure, 2 c. c. of solution No. 2 are poured, which are mixed with the bath in the dish, and in which the plate is again placed. After a few seconds again 2 c.c. of solution No. 2 are added, and so on, until the image begins to appear. As soon as it is faintly perceived, the addition of the alkaline solution should be interrupted; only, if it is noted that the plate lias been under-exposed, the solution No. 2 should be added also after the high-lights have appeared, but always only 2 c.c. of it at one time. After development the plate is well washed,and then placed for half a minute in a solu tion of Tartaric acid 25 grammes Water 1,000 c.c. which prevents the negative turning yellow in the fixing bath. The plate is again well washed, and then fixed in a 20 per cent, solution of hypo. To develop a time exposure, the bath is prepared as follows:— Water ... ... ... ... ... 80 c.c. Solution No. 1 ... ... ... ... 40 ,, Solution No. 3 ... ... ... ... 4 ,, The further treatment is the same as with instantaneous exposures. If the bath becomes weak, after a larger number of plates have been developed in it, it may, not withstanding, be used if prepared as follows: — Old solution ... ... ... ... 100 c.c. Solution No. 1 ... ... ... ... 25 ,, and if, as described above, 2 c.c. of the alkaline solution are added at one time. Brown and Reddish Tones on Bromide Prints hi/ Eikonogen Bevelopment.—Dr. F. Stolze, editor of the Photographie Nachrichten, publishes in the columns of that journal a very practical and useful process of producing warm tones on bromide prints by the use of the eikonogen developer, combined with a modification of the tone of the deposit in the finished print. For the first development he uses an eikonogen developer of the following composition:— Solution No. 1. Sodium sulphite 20 parts Eikonogen ... ... ... ... 4 ,, Dist. water ... ... ... ... 300 ,, Solution No. 2. Carbonate of potash 50 parts Dist. water ... ... ... ... 300 „ In the case of normal negatives, 50 parts of solution No. 1 are mixed with 20 parts of solution No. 2, and with 150 to 180 parts of dist. water. In the case of soft nega tives more of solution No. 1 is taken, whilst in the case of hard negatives, the bulk of solution No. 2 and of the water should be increased. The temperature of the solu tion should be at least 59? to 609 F. In the case of over- exposure from soft negatives, 10 to 25 drops of a solution of potassium bromide 1:10 should be added to 100 c.c. of the above mixture. By this means very agreeable, slightly yellowish-brown tones are obtained. In order to produce brown or reddish tones, it is, however, neces sary to modify the tone of the finished print, which is done by transforming the silver image into bromide of silver, and by re-developing it with eikonogen. For this purpose the following two solutions are prepared :— A.—Sulphate of copper 1 part Dist. water 100 parts B.—Potassium bromide 1 part Dist. water ... ... 100 parts The two solutions are mixed, and the prints are bleached in the mixture. They are then washed five to six times, to remove the copper bromide as completely as possible. The prints are then, in daylight, treated with the above eikonogen developer, which for this purpose is composed as follows :— SolutionNo. 1. ... ... ... 50 parts Solution No, 2. ... ... ... 20 ,, Dist. water ... ... ... ... 4,930 ,, The action is, of course, very slow, but entirely uniform. The tone is passing from a very vivid red-chalk tone through all shades of reddish-brown and blackish-red to a dark violet black. To prevent the toning process continuing in the washing water, the prints are placed in a bath of— Citric acid ... ... ... ... 1 part Water ... ... ... ... ... 100 parts They are then again washed, and dried. According to the degree of the second development, the character of the original picture must be a different one. In order to obtain a red-chalk tone, the picture should be a little over-developed, so that all the tender half-tones are too dark without the shadows being, however, too heavy. For darker tones the original picture should always be of a greyer tone, and the high-lights should appear entirely white, even slightly devoid of details. During the second development all these apparently wanting tones will make their appearance. This method may, therefore, be used in the case of quite flat original pictures in order to in tensify them successfully. It is necessary to free the prints completely from the developing solutions by washing, to prevent their turning yellow afterwards. This process is at the same time an excellent means for intensifying flat negatives. ■— e- THE RESTORATION OF DARKENED EIKONOGEN. An evil complained of a great deal in the development with eikonogen is the circumstance that the eikonogen will change soon if proper care is not taken ; that is, it will become brown and be useless for developing solu tions. We have been asked the question repeatedly: Can eikonogen, after it has become brown, be restored again so as to be fit for use ? and in view of this really favourite developer, it will certainly be of general interest to dis cuss this question a little closer. It may be remarked beforehand that it is possible to make the changed eikonogen useful again, and in different ways. For instance, by the following process : Prepare a not very concentrated solution of sulphite of soda, and add to the same one-half the weight of eikonogen to be so treated. If the solution is alkaline, it is neutralised and made to boil in a glass flask. After this the rest of the eikonogen is added, and the cooking is continued until the eikonogen is completely dissolved, or nearly so. In the beginning only enough liquid should be taken to make the solution saturated ; it is also good if a little of the eikonogen remains undissolved. The proportion may, for instance, be 500 c.c. sulphite solution to 90 to 100 grams of eikonogen. The solution is then cooled off quickly by stirring it with a glass rod to accelerate crystallisation. A powdery deposit will form, from which the coloured liquid can be separated by decanting. This deposit is finally washed with cold alcohol, and dried at a moderate heat. In this manner an almost colourless product is obtained,