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He invented the art of making porcelain. A few simple observa– tions upon fragments of glass, porcelain, and pottery, convinced him that china was nothing more than a demi-vitrification ; now a demi-vitrification may be obtained. either by exposing a vitrifiable matter to the action of fire, and
withdrawing it before it is perfectThe same experiments, which
M. Reaumur was the first that reduced thermometers to a common standard, so as that the cold indicated by a thermometer in one place, might be compared with the cold indicated by a thermometer in another; in other words, he prescribed rules by which two thermometers might be constructed, that would exactly coincide with each other through all the changes of heat and cold: he fixed the middle term, or zero, of his division of the tube, at the point to which the liquor rises when the bulb is plunged in water that is beginning to freeze, he prescribed a method of regulating the divisions in proportion to the quantity of liquor, and not by the aliquot parts of the length of the tube, and he directed how spirits of wine might be reduced to one certain degree of dilatability. Thermometers construćted upon these principles were called Reaumur’s thermometers, and soon took place of all others. M. de Reaumur invented the art of preserving eggs, and of hatching them ; this art had been long known and practised in Egypt, but to the rest of the world was an impenetrable secret: M. de Reaumur found out and described many ways of producing an artificial warmth in which chickens might be hatched, and some by the application of fires used for other purposes; he shewed how chickens might be hatched in a dunghill; he invented long cages in which the callow brood were preserved in their first state, with fur cases to them to creep under instead of the hen’s bosom, and he prescribed proper food for them of such things as are every where to be procured in great plenty.