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Edwards, Junius David

Publications and source records attributed to Edwards, Junius David.

The testing of balloon fabrics

Report describes methods and materials used in waterproofing and fireproofing airplane fabrics using dopes. The determination of the probable life of a balloon fabric in service by experimental means is of great value in choosing the most suitable fabrics for a given purpose and in pointing the way to improvements in compounding and construction. The usefulness of exposure to the weather for this purpose has been amply demonstrated. Various attempts have been made to reproduce by artificial means the conditions promoting deterioration in service, but without marked success. Exposure to the weather remains the most satisfactory method for this purpose, and a consideration of the characteristics of such tests is therefore important. This report presents the results of a typical series of exposure tests made in 1917.

Edwards, Junius David

Testing balloon gas

In the generation, storage, and use of hydrogen for balloon purposes it is necessary to be able to determine, first, its lifting power, and, secondly, its purity. The lifting power may be determined directly from the specific gravity. Contamination by other gases may be determined by analysis for oxygen, carbon dioxide, etc., by the usual methods of gas analysis. The determination of oxygen is important, since the presence of oxygen in amounts beyond certain limits will make the compressing, handling, and use of the gas hazardous. If the specific gravity of the gas is known, however, it may not be necessary to analyze the gas for oxygen and other gases, because the specific gravity in itself is a delicate criterion of the purity of hydrogen. Report describes a simple, portable apparatus for testing hydrogen, with special reference to its use in balloons.

Edwards, Junius David