Experimental researches on the movement of atmospheric air in tubes / by W.D. Chowne ; communicated by John Bishop.

  • Chowne, William Dingle, 1791-1870.
Date:
[1855]
Catalogue details

Licence: Public Domain Mark

Credit: Experimental researches on the movement of atmospheric air in tubes / by W.D. Chowne ; communicated by John Bishop. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    / area of the tube than to that of the entrance and exit orifices, as the latter were the same in the tube of 3 inches uniform diameter, and in the conical tube on its base, while the revolutions of the disc were 3’0 per minute in the former, and 8’8 per minute in the latter. Fig. 13. Fig. 14. Fig. 15. Fig. 16. When the exit orifice of the tube of 6‘75 inches diameter was re- duced to 3‘5 inches, the rapidity of the revolutions was reduced only about 10 per cent. The influence of temperature in accelerating or retarding the cur- rents through the tubes next engaged the author’s attention; but before entering into direct experiments, he found by very numerous observations, that on some occasions no appreciable difference could be observed in tbe temperature of the atmosphere of the room near the floor and the ceiling, while on others there was a mean excess of 0°'17 Fahr. near the ceiling without causing any perceptible dif- ference in the velocity of the revolutions of the discs. In forty com- parative observations of the temperature of the external surface of the tube (fig. 13) and of the surrounding air, that of the tube was 0'()9 higher; in twenty-three it was equal, but in only five was it lower than the surrounding air. Of thirty-six comparative observations of the temperature of the air within, and external to the tube, by a delicate mercurial thermo-