dise; then to ascertain profits, it will be necessary to subtract the cost from the amount of sales, and the remainder will be the profits. COINS OF THE UNITED STATES The coins at present in circulation in the United States may be classified as gold coins, silver dollars, subsidiary silver and minor coins. The gold coins are the double-eagle, the eagle, the half-eagle, and the quartereagle, weighing respectively 516, 258, 129, and 641⁄2 grains of standard gold; that is, of a mixture consisting of nine parts of pure gold to one part of copper. The pure gold in the eagle weighs, therefore, 232 2-10 grains. These coins are legal tender in unlimited quantities for twenty, ten, five and two and one-half dollars respectively, and they are minted free of charge for whoever brings metal to the mint of the requisite degree of fineness. For nearly half a century after the establishment of the first United States mint, in 1793, the eagle contained 270 grains of standard gold .916 2-3 fine, and the alloy consisted of silver and copper mixed. The change to our present system was authorized by the acts of June 28, 1834, and January 18, 1837. For a time also a seigniorage charge of one-fifth of one per cent was imposed, but this regulation was repealed by an act passed January 14, 1875. Our subsidiary silver coins are the half-dollar, quarter-dollar and dime. weighing respectively 192.9, 96.45, 38.58 grains of standard, or 173.61, 86.805, 34.725 grains of pure silver. The amount of the issue was limited by the acts of July 14, 1875, and April 17, 1876, to about forty-two million dollars, the sum needed to retire the so-called fractional paper currency of that time. This limit has been increased from time to time by special legislation. These coins are legal tender to the amount of ten dollars only, and are reedemable at the treasury or any subtreasury of the United States in sums or multiples of twenty dollars. They are issued in like quantities for lawful money to any person desiring them, and delivered by the government free of charge. At one time half-dimes and three-cent pieces of silver were issued from the mint, but their coinage was ordered discontinued by the mint act of 1873. The minor coins of the United States are a fivecent piece, weighing 77.16 grains, and made of a mix ture of copper and nickel in the proportion of 75 parts of the former to 25 parts of the latter; a onecent coin weighing 48 grains, and consisting of a mixture of copper, tin, and zinc in the proportion of 95 parts of the former to 5 parts of the two latter materials. From 1873 to 1890 a three-cent coin of nickel and copper was also in circulation. These coins are legal tender to the amount of twenty-five cents only, are redeemable at any subtreasury in sums of twenty dollars or more, and are delivered free of charge in similar quantities to any person who is willing to pay lawful money for them. Their supply is regulated by the director of the mint, under the supervision of the Secretary of the Treasury, the purpose being to keep in circulation precisely the quantity which is actually needed for the commerce of the country. RAPID CALCULATION "LIGHTNING METHOD" OF MULTIPLICATION AND DIVISION. To multiply by 125, divide by 8, and call it thousands, because 125 is % of a thousand. To multiply by 122, divide by 8; call it hundreds. To multiply by 622, divide by 16, and call it thousands. To multiply by 64, divide by 16, and call it hundreds. To multiply by 314, divide by 32, and call it thousands. To multiply by 333%, divide by 3, and call it thousands. To multiply by 33%, divide by 3, and call it hundreds. 10 multiply by 50, divide by 2, and call it hundreds. To multiply by 66%, divide by 15, and call it thousands. To multiply by 833%, divide by 15, and call it ten thousands, by annexing four ciphers. To multiply by 83%, divide by 12, and call it thousands. To multiply by 8%, divide by 12, and call it hun dreds, because 8% is 1-12 of a hundred. The reason is similar in each case. To multiply by 166%, divide by 6, anu call it thousands. To multiply by 16%, divide by 6, and call it hundreds. To multiply by 1%, divide by 6, and call it tens. To multiply by 372, take % of the number, and call it hundreds; 872, % of the number, and call it hundreds, etc. We simply reverse these methods to divide. To divide by 10,100, 1,000, etc., we remove the point one, two and three places to the left. To divide by 25, remove the decimal point two places to the left, and multiply by 4. Removing the point two places divides by one hundred; hence the quotient is four times too small; hence we remove the point two places, and multiply by 4. To divide by 2%, remove the point one place to the left, and multiply by 4. To divide by 125, remove the point three places to the left, and multiply by 8. To divide by 12%, remove the point two places to the left, and multiply by 8. To divide by 14, remove the point one point to the left, and multiply by 8. There are about 14 cubic feet in one bushel. Hence dividing the number of cubic feet by 14 gives the number of bushels nearly. To divide by 133%, remove the point three places to the left, then multiply by 3 and divide by 4. To divide by 8%, remove the point two places to the left, and multiply by 12. CONTRACTIONS IN MULTIPLICATION. To multiply by 25 To multiply by 175 and multiply result by 7. add 2 ciphers and divide by 4. add 2 ciphers and divide by 3. add 3 ciphers and divide by 8. add 2 ciphers and divide by 5, METRIC SYSTEM The Metric System has been adopted by Mexico, Brazil, Chile, Peru, etc., and except Russia and Great Britain, where it is permissive, by all European nations. Various names of the preceding systems are, however, frequently used: In Germany, 2 kilogram = 1 pound; in Switzerland, 3-10 of a metre = 1 foot, etc. If the first letters of the prefixes deka, hecto, kilo, myria, from the Greek, and deci, centi, mili, from the Latin, are used in preference to our plain English, 10, 100, etc., it is best to employ capital letters for the multiples and small letters for the subdivisions, to avoid ambiguities in abbreviations: 1 dekametre or 10 metres = 1 Dm.; 1 decimetre or 1-10 of a metre 1 dm. The Metre, unit of length, is nearly the ten-millionth part of a quadrant of a meridian, of the distance between equator and pole. The International Standard Metre is, practically, nothing else but a length defined by the distance between two lines on a platinum-iridium bar at 0° Centigrade, deposited at the Internationa! Bureau of Weights and Measures, Paris, France. The Litre, unit of capacity, is derived from the weight of one kilogram pure water at greatest density, a cube whose edge is one-tenth of a metre and, therefore, the one-thousandth part of a metric ton. The Gram, unit of weight, is a cube of pure water at greatest density, whose edge is one-hundredth of a metre, and, therefore, the one-thousandth part of a kilogram, and the one-millionth part of a metric ton. One silver dollar weighs 25 grams, 1 dime=2%2 grams, 1 five-cent nickel 5 grams. The Metric System was legalized in the United States on July 28, 1866, when Congress enacted as follows: "The tables in the schedule hereto annexed shall be recognized in the construction of contracts, and in all legal proceedings, as establishin, in terms of the weights and measures now in use in the United States, the equivalents of the weights and measures expressed therein in terms of the metric system, and the tables may lawfully be used for computing, determining, 212 |