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weight of grain; or afford ten pounds of wheat, per day, leaving sufficient for seed.
Peas and beans yield in the same proportion. Turnips and carrots are a productive as potui. toes! but parsnips actually double the weight of potatoes !
Oos-Mr, Middleton well observer, " that every acro Would support its than well, on vegetanle food i tør, says he, only let him change his diet to one meal por day, of anlımai food, and he will require the produce of foar acres !". The same author observer also, "thar the marth, or nepriament of a potatoe, in one fourth of its entire weigbli aud that the quantity of March, or nutri ment, on an acre of potatoes, in four timer greater than in an nere of wheat!" "Those, who seek further infor mation on agricultoral subjects, should coneult Poung's Farmer's Kalendar; a work whicla vught to be found in every farm-house,
IV, Metallurgy. 66. Before man could till the ground, digit, hoe it, or plough it, he required the aid of some thing harder than the ground itself; that is to say, he wanted iron or metals. Without iron, he could buve no very useful, sharp instrunient --such as the spade, hoo, plough, soythe, or sickle.
07, llence, till they had discovered the means of obtaining and working iron, men were found to depend for food, on the spontaneous prodao: tions of the earth, and on the flesh of animals. Tholy writ tells us that Tubal-cain (or Vula cau), was the instructor of all those who before the food, worked in brass and iron., 1
038. Viewing the metals in ordinary, usc, we consider them common praductions; but oo art is so curious, as that of extracting metals from the carth, or ore in which they are buried or concealed ; and no discovery or invention was ever more wonderful.
69. Metals are very seldom found in a pure state; but perhaps the first discoverer, having found some metal in a detached or pure state, was led 10 niake experiments on those lumps of shapeless and coarse, but heavy earth; which consist of a mixture of earth and metal, and which are called ores.
70. Gold-dust is frequently found in the sand of rivers; whither it is washed by the rains from the mouutains. This itself might lead to the discovery of metals. Much of the gold used in England, is collected out of the rivers in Guinca, on the coast of Africa. 1 71. Workers of metals, imitate nature wlien they beat and wash their ores; and, having cleared them, in that way, of much of the eartli, they then burn them in various ways; and, at length, get the metal by itself in a pure state.
72. No one, on looking at most of the metallic ores, would suspect them to contain metal : They are, apparently, the ronghest, coarsest, and least desirable stones, or earths; but, on being broken, repeatedly washed, and burnt, (or, roasted, as it is caliud,) they yield Gold, Silver, Copper, Iron, and other nietais.
--786. These ores are found in the veing of mountains, or between the struta, or divisions
of rocks : generally beneath the surface of the ground; and the pits or wells, dux in spaich of the ore, are called mines. The well itself, is called the shaft of the mine. Pits, tion which atoue only in extracted, ale called stonequarries.
74. The deeprat mines are in Hungary, and are about three-quarters of a mile below the surface. Many mines are like towns under ground; oud many miner's pase their whole lives in them. The wont of tiesh air, and the influx of water, prevent mives from sinking deeper.
76. All the substances which form the ground oud earth, are called minerals. Clay in a mineral; all stones are minerals: coal is al mineral : chalk, and, in short, whatever is not aninial or vegetable, is called mineral,
70. The study of minerals has been nietho. dised, and called the science of mineinlogy. In this, as in many other branches of science, little more, however, hun been elected, than to uituin a mystcuntio classification and pomen. clature.
77. All minerals, i.e. all earths, koils, stones, und metals, aro scientifically divided into four clasaca. 1. Forthy Miucralga, being all sucli, as are vold
of taste and smell, light and brittle; as mill. stone, dint or silex, clay, sand, crystula, mpat, eypeim, niabaster, chalk, stonen, cotucliane, Jasper, topuxes, sapphires, tubics, chevalis,
and dimnionda. II. Suline Minerals --being suchi, # have a
pungent taste, and are heavier, softer, and partly transparent; as common salt, alunn,
nitre or salt-petre, and borax. Ill. Inflammable Minerals--being lighter, brit
tle, opaque, and never feeling cold; as coals,
sulphur, black-lead, and amber. IV. Metallic Minerals--being heavier, opaque,
cold, ductile, capable of being drawn into wire, and malleable, capable of being worked into shape. These consist of gold, sil. ver, &c. : see paragraph, 622, for other particulars.
78. Many metals exposed to the air become dusty; that is to say, they imbibe a part of the air called oxygen, and the rust is called an oxide. If melted and heated on a fire for a considerable time, they also imbibe oxygen from the atmosphere; and turn into substances called oxides: the process is called oxidation.
79. If 10 lbs. of lead be melted and heated in this manner, it will be converted into an oxide called red lead; and the red lead so produced, will be found to weigh 11 lbs., the additional pound arising from the imbibed oxygen.
80. Oxides may be converted into metals again, by depriving them of their oxygen. In the example of red lead, if it be burnt again with powdered charcoal, the charcoal will detach the oxygen from the oxide, and the lead will be obtained again in its pure state: this process is called reduction,
81. Modern chemists consider the whole earth as inetallic; and all the different earths to be
nothing more the various oxides, or rusts of metals, produced by the continued action of the air and water on them; and capable, by suitable means, of being reconverted into meials !
82. Platina is the heaviest of all metals, being 23 times heavier than water; but it is a modern discovery. The colour is light grey, and it cannot be melted in ordinary tires.
83. Gold is 19 tiines heavier than water; and the most valuable of all the metals. It is so malleable, that an ounce of it will gild a silver wire 13,000 miles in length; and it may be beaten into leaves; 300,000 of which, are only the thickness of an inch.
84. Silver is 11 times heavier than water: and next to gold in beauty; such is its ductility, that it may be drawn out in wire finer than a hair,
85. Mercury, or Quicksilver, is 14 tinues hicavier than water; and is remarkable for being liquid like water; and for not becoming solid except in cold greater than that which renders water solid,
86. Copper is 9 times heavier than water; and is found in great abundance in the nines in Sweden, and also in the isle of Anglesey. It unites well with other metals; and forms a variety of useful compounds.
37. Iron is 8 times heavier than water; and is the most useful, and, in England, the most abundant of all the metals. It mixes with the animal, vegetable, and mineral kingdon. It is melted with more difficulty than gold, silver, or copper; and it usefully strikes fire with fint.