Publisher's Synopsis
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1898 edition. Excerpt: ...of heat emitted by the light at the side, or on a level with the center of the light, is about one-twelfth of the heat above the light. By holding the thermometer one foot above the light and also at a point one inch from the side of the light the thermometer registered the same number of degrees of temperature in both locations. Tests made with a 16-candlepower incandescent electric light gave a temperature at one inch above the globe equal to the temperature at one foot above a three-foot gas burner, or, in other words, the gas flame emitted from 140 to 160 times as much heated air as the electric light did. At about 16 inches above the electric light the thermometer showed no change or rise in temperature. The results of tests made with the arc electric light of 2, oco-candle-power, the same as used for the lighting of streets, are practically the same, according to the amount of light emitted. Thus it is plain to be seen that lights that are the result of combustion, of which gas is the principal one in use in nearly all auditoriums, when used for illuminating purposes must, by the natural law of heated air, produce draughts, currents, etc., to the great injury of the acoustic properties of the room. By numerous tests and comparisons it has been found that the lighting of an auditorium with gas is more injurious to its acoustics than any heating apparatus now in use, especially in its effects on the auditors in the gallery. The amount of heated air thrown off by a common four-foot gas jet is equal to about one square foot of heat-generating surface of any of the modern hot-air or steam-heating apparatus on the market. A gas chandelier with six or eight four-foot burners will give more heat than a steam radiator that has a heating..
