Book Description

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. 1881 edition. Excerpt: ...an adjusting lever. A trough or canal 105 feet long, 5 inches wide inside, and 8 to 9 inches deep, is placed at the orifice quite horizontally, and the bottom of the orifice from the reservoir is in a line with the bottom of the inside of the 1 Abbe-Bossut, Traitf d?Hydrodynamiqut, vol. xi., pages 196 to 206. trough. The sides are also in a line with the edges of the orifice. The trough is made of strong fir planks polished inside, with quite smooth joints. c. In the experiment I wish to notice, the sluice is opened exactly half an inch. I translate Bossut's words: "It is necessary to observe that in every experiment the velocity of the current is not uniform, that is, that each separate division of the canal will not be traversed in equal time, and that the velocity diminishes as the water recedes from the reservoir. This movement has some particulars which merit observation. When we raise the sluice the water is ejected along the bottom of the canal, and at first keeps only in this direction. But as it proceeds it meets with resistance, swells on itself, and its surface takes the form shown by dotted lines in the above engraving E M G. Then it falls by its own weight from the highest point M, and a part of the water returns towards the reservo1r, following the direction M N. There is, therefore, in the part C M of the canal two currents which are going in different directions--the one formed by the deeper water which goes in the direction C F, and the other by the surface water which returns in the direction M N, and which is very apparent at the commencement. This effect terminates at a point N at about 12 feet from the orifice E C. Little by little the swelling of the water diminishes, although it always exists, until finally it...