The citizens of the United States of Notth America, who cultivate with success the employment of ma chinery, as we may judge from their numerous steam boats and other machines, both for naval and other purposes, appear to be the first persons who have em ployed steatite in the large way. It is not, however, used alone, but mixed with a small quantity of oil, suet, or tar. They commence by reducing it to a very fine powder, and then mixing or triturating it with the material intended to render it more unctu ous. The first experiments on using it were made at Lowell, in the state of Massachusetts ; and the coach men and wagoners have found it highly beneficial.
Mr. Moody, superintendent of the great iron works established upon the mill dam near Boston, has af forded us means of estimating the advantage to be derived from the use of this new mixture. In one of the works is a wheel of great size and weight, which makes from 75 to 100 revolutions per minute, and turns upon necks or gudgeons of five inches in diame ter. It has moved with this speed during three, and sometimes five, weeks together, without renewing the lubrication of the gudgeons. Nevertheless, Mr. Moody thinks it best to renew it oftener. The ma chinery, of which this great wheel forms a part, manufactures about 200,000 pounds of iron per month.
It is to chance, that we are indebted to the dis covery of this valuable employment of steatite, the use of which is now continually extending in the United States ; and will also, no doubt, be speedily adopted in Moleon's Reettiel Industriel.
.additions by the Editor of the Technological Reposi is also used in the United States to line furnaces with ; a type founding machine, sent from thence, and patented here, had a furnace of this kind. And the Editor lately saw, in the hands of Mr. Lemuel Wellman Wright, engineer, a cubic mass of it, a foot square, and which had been sent to him by an American friend. lle had sawn off a portion of this block, and exposed it to the heat of his fire for several hours ; after which it had assumed the ap pearance of a mass of mica, still, however, cohering together. The Chinese also make small portable furnaces of steatite.
The lapis ollaris, or potstone, is also another varie ty of steatite. Bishop Burnet gives the following ac
count, in his travels, of the mode of using it in Swit zerland. " There arc a sort of pots, made of stone, which arc used, not only in all the kitchens here, but also in those of almost all Lombardy, called Lavege. The stone feels oily and scaly, so that a scale adheres to the finger of any one that touches it, and it is somewhat of the nature of slate. There are but three mines of it known in these parts ; one near Chavcnnes ; another in the Valteline; and the third in the Orisons ; but the first is much the best. They generally cut it round in the mine, in masses of about a foot and a half in diameter, and a foot and a quar ter in thickness ; and they work it into shape in a mill, where the blocks of stone are driven about by a wheel, set agoing by water ; and which is so ordered, that he who manages it, turns the outside of the stone, first, till it is quite smooth ; and then separ ates one pot after another, by small and hooked chisels, by which means he makes a nest or pots, one within another; the outward and biggest one, being as large as an ordinary cooking pot, and the inward one, no larger than a common pipkin. These pots they arm with hooks and circles of brass ; and so they are used by them in their kitchens. One of these pots heats and boils sooner than any metal pot ; and yet the bottom is twice as thick as that of a metal one. It never cracks by the heat, nor gives any sort of taste to the liquor that is boiled in it ; but if it falls to the ground, it breaks, as it is very brit tle ; nevertheless, it is soon repaired again ; for they piece their broken pots so close, by sewing the broken parts together with iron wire, which completely fills the holes they make to receive it, that there is no breach made, although no cement is used. The pas sage to the mine is very inconvenient, for they must creep for near half a mile through a rock, which is so hard, that the passage is made not above three feet high ; and so that those who draw out the stones, creep all along upon their belly, having a candle fastened to their forehead, and the stone laid upon a sort of cushion, made for it upon their hips. The stones are commonly two hundred weight.''