INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 18, No. 1
The end item is exposed in its eitirety.
aidcd by mites a i d other insects which are present in the chamber (mites are desirable in testing such items as optical instruments). Samdes are exmsed to deterioration caused-by bacterial ,
It is desirable to correlate the results of tropical chamber tests with other types of testing. Comparisons with t r o p i d field tests and with soil burial and pure culture tests are being made. As part of n study of commercially available fungicides applied to fabrics that is now being carried aut a t the Engineer Board, ten Figure 4. Photographs Take!n through Telescopes after P Months' Exposure in Chamber thousand fabric samoles are b&e Lett. Unhealed Right. T I I ~ X O P ~boated with radium foil to the Panama Field Station of the National Defense Research Committee. and the results of these tests will be correlated with the results obtained from similar samples exposed in the Table I. Fungi Introduce lropical Testing Chamber chamber. Cork, leather, and optical instruments will also be exSpeck S0"X Species S0"roe posed in the chamber a t Panama and the results compared. *,."Gal . PI ?r'idli"'rn ". India The fungi that are now present in the tropical testing chamber Hoilandia P IW'ieii1ium e3Ja"mLm Loon1 South Phoific PI :nicillizrmsp. New Guinea BR being identified. ,Eight of the species originally introduced Sovth Pacific A ,spernillvs o r y i a e Chins south paoifio have already been recognized as still present and several others South Pacific P I?"icillium 8P. South Pacific Ci ~ ~ $ ~which ~ were $ probahly ~ & introduced with the leaf mold have been South Paoifio A New Guinea A spergiizvs nioer Local identified.
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India New Orleans South Paeifio New Orleans
South Psoifio South Pacific M UCDI sn. South Pacific A spe7giliusae7sicolor South Paoifio
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chosen because i t provides a-temperatGe drop and a relative humidity rise comparable to conditions which oocur in the tro ies & k g provides breathing for partially closed systems such as optical instruments. Cyclin canses condensation which provides a film of water ideal for fungus growth and excellent conditions for the corrosion of metals. The chamber was inoeulated by the addition of spare suspensions of 24 species of fungi obtained chiefly from the Pacific area, which were disseminated hy means of spray, and by the native fungi occurring on the leaf mold placed on the floor of the ohamber. The list of the 24 species of fungi is given in Table I. Other fungi were undoubtedly brought into the chamber by the air and by test specimens. Wooden shelves are employed for the shelf exposure of materials because wood provides a source of nutrient for fungi, and also because exposure on wooden shelves duplicates storage conditions in the field. Suoh items as fabrics, small pieces of cork, etc., are hung from glass rods with glass hooks. Packaged materials and large objeccs are placed directly on the shelves. Figure 3 provides a close-up of test specimens being exposed in and on the wooden shelves. The center of the chamher is used for the ex^. " . . .. . . POSUre
