Knight's American Mechanical Dictionary; A Description of Tools, Instruments, Machines, Processes, and Engineering; History of Inventions; General Technological Vocabulary; And Digest of Mechanical Appliances in Science and the Volume 2 (Paperback)

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. 1884 edition. Excerpt: ...Reaumur or 54 Fall." In deducing the length of the quadrant of the meridian, the arc measured by Bouguer and La Condamine in Peru, in 1736, was taken as an element. More recent and extended measurements at different points of the earth's surface indicate that the data upon which the metric determinations were founded were inadequate for ascertaining the exact variations in curvature of this irregular ellipsoid at different latitudes, and that consequently the meter is not exactly what it should be, but 10,000,000 meters fall short, according to Sir J. F. W. Herschel, by 4,008 feet of measuring a meridional quadrant. This error, amounting to but of an inch to the meter, is disregarded. As before observed, the meter is the basis of all measurements. From it are derived the following units: --Of area; the are, --1 square decameter. Of capacity; the liter, --1 cubic decimeter. Of weight; the grnm, --1 cubic decimeter of water. The names of the graduations below the unit are formed from the Latin, and above the unit are formed from the Greek, as follows, the unit being 1: --Measures of Capacity. The unit for the measure of volumes is a cube whose edge is rV of the meter; that is, a cube whose edge is 3.937 inches. It is called a Liter, and is Ttatd" part of a cubic meter. The United States, however, led the way in a decimal currency. The metric system, though adopted in 1795, was not fully carried into effect until 1810. It is now employed throughout a large part of Continental Europe, and seems in a fair way to be generally adopted at some not very distant day in the United States, where it may now be legally employed at the option of the parties interested. Met ro-chrome. A color-measurer. Invented by Field and described in his ..".