This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Diluting The Developer. The effect of diluting the developer for prints is just the opposite in action to what it is in developing plates. A diluted developer will give stronger and more contrasty prints while a full strength developer will produce softer prints. Therefore, when you have dense plates to print from, use the developer full strength and print on the special or special portrait paper. It is advisable to make the prints first from the heavy negatives. When you come to print your thin plates dilute the developer at least one-half and use the carbon or regular paper. Remember, the more you dilute the more contrast can be produced and the action of the developer will be just so much slower. You must, however, be careful as to going to the extreme, or the tone will have a tendency to run into an olive, or green. Remember also, the addition of a few drops of 10% solution of bromide of potassium will aid you in obtaining contrast. If the prints do not develop clear, bromide must be added until they do. Always remember, however, that care must be exercised not to add too much bromide, or the resulting tone will be green or olive. To rectify an excessive addition of bromide add more of the fresh developer.
Caution. It is essential that the hands be perfectly clean and dry when handling paper during printing. They should also be thoroughly cleansed before developing. Never attempt to develop a print after the hands have been in hypo without first washing and drying them thoroughly, removing every trace of hypo.
Acidified Rinse Water. Immediately after development the prints may be rinsed in clear water and placed in the fixing bath. It is, however, advisable to slightly acidify the rinse water by adding 40 to 60 drops of acetic acid to 2 quarts of water. This acidified water will prevent mealiness and muddiness upon the surface of the prints and will also prevent yellow stains, as it will immediately stop the action of the developer.
Fixing. When the print is fully developed it should be dipped either into plain water, or the above acidified water for a few seconds to remove the surplus developer, then fully immersed in the acid fixing bath. In this fixing bath the prints must be kept moving for the first half minute to insure uniform and thorough fixing and to prevent stains from uneven action of the hypo on different parts of the print. In order to obviate the necessity of frequently washing the hands to avoid mixing hypo, adhering to the fingers, with the developer, and also in moving the prints from one tray to another, a small stick may be employed, or a glass rod, or even a small glass funnel (using the stem as a handle). Allow the prints to remain in the fixing bath 15 minutes. Then let them lie for an hour in a tray into which water is running slowly from a faucet; or in water which is frequently changed during the hour. Of course, a number of prints may be placed in the fixing bath, or in the wash water, at the same time, care being used in the fixing that they do not follow each other into the bath too rapidly. Also that each one is moved about for a few seconds before it is allowed to sink to the bottom and remain undisturbed. Prints are often spoiled by neglect of this precaution. If this is attended to, no harm will be done if the prints remain for a longer time in the fixing bath, except in hot weather, when they may turn brown, as the bath becomes warm. Use plenty of fixing bath. Do not attempt to fix prints in too small a solution. A pint is a small enough quantity, even if you intend to fix only a dozen prints. As the fixing bath keeps for a long time a larger bath should be made up and used continually without renewing. A one gallon bath will fix one hundred 4x5 prints, or their equivalent. For large batches and professional use, large quantities of the bath should be made up.