Page:Popular Science Monthly Volume 29.djvu/97

Rh of a collection may reasonably sacrifice a few drawings in his lifetime (and the sacrifice is only partial) to the satisfaction of seeing them more frequently and of ornamenting his walls with them. An intermediate plan with regard to water-color drawings is to have case-frames that allow one drawing to be easily substituted for another when the mounts are of the same size. The drawing is then exhibited for a short time only, and the owner has the refreshment of change on the walls of his room. The same plan may be followed with prints, simply for the sake of change.

With regard to the keeping of drawings in portfolios, there are reasons for believing that portfolios are not entirely safe. I have known a case in which prints in portfolios suffered visibly from damp, when every possible precaution seemed to have been taken for their preservation. The portfolios were kept in a closet six feet by eight, which was selected because it had no outer wall, and, though there was not a fireplace in the closet itself, the door of it opened on a room where a fire was constantly kept. The closet was believed to be the driest place in the house, and the house itself was not in a damp situation, being exposed to all the winds that blow, and built upon rather elevated ground. It happened, however, that the outer walls were built of a porous kind of sandstone, which retained moisture in the winter, and as the portfolios in which the prints were kept were made of mill-board, also a retainer of moisture, the prints were really damp in spite of the carefully chosen closet. They showed the signs of damp as much, almost, as if they had been hung upon a damp wall with a mill-board backing to each frame. It is plain, then, that the portfolio does not afford absolute security, and, indeed, the mill-board of which portfolios are commonly made is in itself an element of danger. Shallow tin boxes, with removable lids made like those of pill-boxes, are much safer than the common portfolio. I have alluded in another paper (on the "Poor Collector) to cabinets with shelves of thin wood separated from each other by small intervals. Prints or water-color drawings may be kept in such cabinets without other protection than a sheet of paper as a protection against the small quantity of dust that finds its way into the interior. The cabinets should be placed in rooms where there are regular fires, and when the room is thoroughly warmed the doors of the cabinets should be occasionally left open and their contents exposed to the air. As to the wood of which they are to be made, it should be one of the least absorbent woods.

Well-closed cabinets or tin boxes are the best protection against dust. If portfolios are used, they ought always to have flaps, as without them dust is sure to get in and spoil the edges and sometimes part of the margins of the prints. The effect of dust in course of time is to discolor paper permanently. Suppose you lay a sheet of paper on another that is rather larger, so that the second shall not be entirely