Scientific American Supplement, No. 643, April 28, 1888 by Various
page 67 of 136 (49%)
page 67 of 136 (49%)
![]() | ![]() |
|
in use is held by him. By counting the strokes which occur during a
given period of time, the number of revolutions during that period can readily be ascertained, and from that the velocity of the current to be measured can be computed in the usual way. When the apparatus is submerged in water, by a rope held by the observer, it will at once adjust itself to the direction of the current. The force of the current, acting against the wings or blades of the propeller wheel, puts the latter in revolution, and the tube, D, will be carried around, and the sliding weight, according to the position of the tube, will drop toward and bring up against alternately opposite ends of said tube, making two strokes for every revolution of the shaft. [Illustration] * * * * * THE FLOWER INDUSTRY OF GRASSE. A paper on this subject was read before the Chemists' Assistants' Association on March 8, by Mr. F.W. Warrick, and was listened to with much interest. Mr. Warrick first apologized for presenting a paper on such a frivolous subject to men who had shown themselves such ardent |
|