A History of Hindu Chemistry from the Earliest Times to the Middle of the Sixteenth Century A.D. v1.c13.2

v1.c13.2

'This combustibility of the diamond appears to have been observed at an early period, although the fact does not seem to have attracted the general attention of the older chemists, as statements of a contrary character are recorded by them. Thus, for instance, Kunkel states that his father, at the command of Duke Frederick of Holstein, heated diamonds in his gold-melting furnace, for nearly thirty weeks, without their undergoing any change. It is to Newton, however, that we owe the first argument which went to prove that the diamond was capable of undergoing combustion on account of its high refractive power, a property characteristic of the class of oily bodies. In the second book of his *Opticks*, Newton says upon the subject, "Again the refraction of camphire, oyl-olive, lint-seed oyl, spirit of turpentine and amber, which are fat sulphureous unctuous bodies, and a diamond, which probably is an unctuous substance coagulated, have their refractive powers in proportion to one another as their densities without any considerable variation." The conclusion to which Newton was led by theoretical considerations was experimentally proved to be correct in the year 1694-5 by Averami.