298. Gross Weight is the weight of the goods together with the box or whatever contains them. 299. Net Weight is the weight of the goods only. MINIMUM WEIGHTS OF PRODUCE. The following are the minimum weights of certain articles of produce, bought and sold by the bushel, according to the laws of the United States: *The weight of salt per bushel as adopted by different States varies from 50 to 80 pounds. Coarse salt in Illinois is reckoned at 50 pounds, and in Pennsylvania at 80 pounds per bushel. Fine salt in Illinois and Kentucky is reckoned at 55 pounds, and in Pennsylvania at 62 pounds per bushel. DIAMOND WEIGHT. 301. Diamond Weight is used in weighing diamonds and other precious stones. 1. The unit is the carat, which equals 3.168 Troy grains. The carat grain equals .792 of a Troy grain. 2. The carat of weight should be carefully distinguished from the assay. carat. The former denotes absolute weight, while the latter is used to denote the fineness, or purity, of gold in coins and jewelry, and means part. Thus, gold 14 carats fine contains 14 parts pure gold and 10 parts alloy. 35. Reduce of a pwt. to the fraction of a pound. 36. Reduce of a to the fraction of a pound. 37. Reduce of an oz. to the fraction of a ton. 38. Reduce .275 gr., Troy, to the fraction of an ounce. 39. Reduce 53 33 20 10 gr. to the decimal of a pound. MEASURES OF EXTENSION. 303. Measures of Extension are used in measuring lengths, distances, surfaces, and solids. 304. Measures of Length are used in measuring distances in any direction. 305. A Line is that which has length but not breadth or thickness. Its extent is estimated by ascertaining how many times it contains some definite length, regarded as a unit of measure. LINEAR MEASURE. 306. Linear, or Long, Measure is used in measuring lines, or distances. 1. The standard unit of length is the yard, from which all other measures of length are derived. 2. The yard is divided into halves, quarters, eighths, and sixteenths, for measuring goods sold by the yard. 3. The length of a degree of latitude varies. The average length, 69.16 miles, is the standard adopted by the United States Coast Survey. 4. The following denominations are used: The span = 9 inches; the common eubit 18 inches; the sacred cubit = 21.888 inches. SURVEYORS' LINEAR MEASURE. 308. Surveyors' Linear Measure is used by surveyors and engineers in measuring the dimensions of land, length of roads, etc. 1. The unit employed by surveyors is the Gunter's Chain, which is 4 rods, or 66 feet long. 2. An Engineer's chain, used by civil engineers, is 100 feet long, and consists of 100 links. In computing, links are written as so many hundredths of a chain. 40. Reduce of a foot to the fraction of a rod. 41. Reduce .475 of an inch to the fraction of a yard. 42. Reduce of a foot to the fraction of a mile. SURFACE MEASURES. 310. A Surface is anything that has only length and breadth. Thus, the floor, a face of a wall, or the outside of anything is a surface. 311. An Angle is the difference in the direction of two lines that meet. The point at which the lines meet is called the Vertex, and the lines are called the sides of the angle. 312. A Square is a plane (flat) surface that has four equal sides and four equal angles. A square inch is a square, each side of which is one inch long. A square yard is a square, each side of which is one yard long. The angles of a square are called right angles. D B ANGLE ONE SQUARE INCH 313. A Rectangle is a plane surface that has four straight sides and four right angles. A square is a rectangle which has four equal Α sides. 314. The Area of a surface is the number of square units it contains. C Thus, if a rectangle is four units long and 3 units wide, it may be divided into 3 rows of squares with 4 square units in each row, making 12 square units in all. Hence, the area is 12 square units A B SQUARE E B RECTANGLE |