A Manual Of Photography

OK FIXING THE PHOTOGRAPHIC PICTURES. 215 “Make in a bottle the following solution:—Filtered water, about a pint and a half; hyposulphite ot soda, about three ounces; cover the bottom of a dish with this, and plunge in your negative proof, taking care to avoid air-bubbles: this dis- solves the bromo-chloro-iodide of silver, but does not attack the gallo-nitrate of silver, which forms the blacks. “Never put more than one proof at a time in the bath; but you may use it for several proofs one after the other. “If you examine the proof as a transparency after it has re- mained some time in the bath, you may be tempted to think it is lost, as in some places spots will appear from the iodide ot silver not being completely taken away ; but it you wait until it is removed, which you will know by the disappearance ot the yellow tint, you will be astonished at the whiteness and trans- parency of the paper, as well as at the beauty ot the blacks in the image. . . “It will require for this, to remain in the hath trom liait an hour to three quarters; you will then wash it in several waters, and leave it in a basin of clear water for three quarters of an hour ; then let it dry spontaneously by hanging it up ; the proof is then quite unalterable by light, as there remains nothing more in the paper than the gallo-nitrate of silver, which is black. “Fixing by means of the bromide of potassium is not so durable, because it does not remove any of the materials used in preparing the paper. It may, nevertheless, be ot great use in travelling, and when it is required to make several proofs one after the other; because then you avoid touching the hyposul- phite in preparing the negative paper, which spots at the least contact with it. “ You may thus place the whole of your negative proots together in this bath.. “Water, a pint and three quarters; bromide ot potassium, 360 grains., .. “ In taking the proof out of the bath, you must was h it in several waters and dry it ; it should be kept in the bath at least three quarters of an hour, but, if you leave it in tw o or three hours, it will not injure it. Such is M le Gray’s statement, and so it is rendered by Ins English translator, Mr. Cousins; but I believe the quantity of the bromide of potassium to be by far too large and that the pictures would sustain less injury by using a solution of one half the strength indicated. His process for fixing the positive pictures contains some important bints. “ Dissolve in a bottle hyposulphite of soda, 1500 grains; “ Filtered water, nearly a quart.