This section is from the book "Modern Photography In Theory And Practice", by By Henry G. Abbott. Also available from Amazon: Modern photography in theory and practice: A hand book for the amateur.
The dark room question is a serious one and you should not be in a hurry about building one until you lave a pretty thorough understanding of the requirements of the art. We never knew an amateur whose first dark room suited him perfectly. He generally enlarges it and makes extensive alterations within a year or two after building. Give the question a little serious thought and it may save you considerable time in rearranging and rebuilding, to say nothing of the expense involved. The location is the first consideration, and in choosing this, much depends upon whether you occupy your own house or rent one and the style of the house itself. Stables and outbuildings are as a rule not desirable for the location of dark rooms because they are generally not heated in the winter, and great care must be exercised to select a location where your liquid chemicals will not be liable to freeze and burst the bottles in which they are confined. Again, it is pretty cold work developing and washing plates where there is no heat and the thermometer is ten below zero. If your house has a basement, say seven or eight feet in height, with a furnace, this will be the place for your dark room. It will be generally be found quite cool, even in the very warm days of summer and warm enough for comfort in the coldest days of winter. If it has no furnace your liquids are liable to freeze, but much depends on the construction of the house and its foundation. If it is safe as regards freezing, then it can be heated to a comfortable degree for working by means of an oil or gas stove prior to the time you wish to do your developing. Next to a basement a small room or good sized closet is desirable.
If a basement or small room is selected and a window can be used, so much the better, for it is desirable to air the dark room from time to time, particularly if you are a smoker, or if you use oil in your dark room lamp, or both. If a window is used it should be carefully covered with at least two thicknesses of post office paper, ruby fabric (a substitute for ruby glass), or black paper. The casings of the window should be examined carefully after this and all cracks covered by pasting over them heavy red express or black paper. The window should not be relied upon for light even when working in the day time and it would, of course, be out of the question at night.
When you have selected a location it will be well to take a piece of paper and lay out a ground plan of your proposed dark room before starting to build. Fig. 20 is a ground plan and Fig. 21 a sketch of a dark room. It is an actual reproduction of a dark room built by an amateur friend, with some minor changes. This dark room is the best fitted and the handiest we have ever seen, either amateur or professional, and is an excellent one to model after. The floor of the dark room is three inches above the basement floor so that it is dry at all times, as the air circulates freely under it. It is practically six feet square. The door extends to the basement floor, so there is no necessity of tacking felt to the bottom of it to keep out white light.
The sink, including the two ends, is about four feet in length. The water pipe and the drain pipe enter the sink at the left hand end and at the right is a convenient platform on which to place plates to dry, etc. This sink is about five inches deep and is built of one-inch pine stock. After connecting up the plumbing the sink was given one good coat of white lead, the cracks being first filled in with the stiff white lead by means of a putty knife. When this coat was thoroughly dry it was given three coats of asphaltum mixed to the consistency of paint with benzine. The coats of asphaltum were given at intervals of twenty-four hours, so that one coat was thoroughly dry before the next was applied. The slats in the center rest on the top of the sink and are joined together, and they can be readily removed when desired. The developing tray is used on this rack and any developer which is spilled, does not run onto the floor but runs down into the sink.
It will be noted that this dark room is lighted from the outside, which is really the only good way, if you value your health and desire to keep the dark room cool in summer. There are cases in which it is not possible to so light a dark room, but where possible it is always advisable. In this instance a window six inches square is cut through the partition directly over the center of the sink. A ruby and an orange colored glass are mounted in frames and these frames run in wooden tracks and pass one another so that either or both glasses can be used. The ruby glass runs in the track nearest to the light. The light is an ordinary kerosene lamp placed on a bracket just outside of this window. Gas, of course, could be used as well as a lamp. Immediately under the platform at the right hand side of the sink is a series of six drawers which are convenient for storing away the various devises and odds and ends which the photographer is bound to fall heir to and which accumulate so rapidly.
Immediately above the sink is a shelf four feet long, on which is kept the bottles holding the developer, and those solutions which are most frequently used, the graduates, funnels, and the bromide solution. Beneath the shelf the dusting brush, scissors, print roller, vig-netter, kits etc can be kept on suitable hooks or nails. To the right is a towel and rack. Next to the bottles on the shelf is a rack built for trays, so they can be placed on their sides to dry. This shelf can also be used for holding plate boxes, etc. The book shown in the illustration, on the shelf, next to the plate rack, is the scrap book, which will be described later on. Beneath the sink is a good place to keep your hypo bath, and this is the very best place to keep it, as you are sure not to get it mixed with the other chemicals.