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 where we can say without reservation that our preparations are permanent, permanent to a degree only dreamed of within the last twenty years, we feel justified in taking extreme measures to insure the future care and preservation of these preparations. The elephants and rhinos can be made as permanent as bronze for endurance under all conditions, but the other animal groups with their backgrounds and with accessories necessarily made largely of wax cannot be thus exposed. That they shall not suffer from excessive light and from changing atmospheric conditions, they will be placed in two great alleyways on either side of, but practically outside, the hall, hermetically sealed off from the hall proper and also from the outside atmosphere. Thus each group will be absolutely protected from changes in temperature and humidity. Each group will be in fact within an individual compartment, and allowed to "breathe" only the air of the alleyway, which is filtered and dried and kept at a uniform temperature throughout the year. Artificial light will be used for these groups.

The amount of light required on them will be relatively small because of the fact that they are to be viewed from a relatively dark central hall. We shall be looking from the hall into the source of light rather than from the source of light outward. Also, reflections can be reduced to a minimum and practically eliminated, owing to the fact that the groups are the source of illumination, by having the glass in the front of the case inclined at such an angle that it reflects only the dark floor.