Page:A History of Hindu Chemistry Vol 1.djvu/99

 life-time (see above p. lxxvi).

We have already had occasion to draw attention to the non-mention of metallic preparations, notably of those of mercury, in the writings of Vána and I'Tsing (p. li). But this is another apt illustration of the dangers of the argumentum ex silentio. In the Vrihatsamhitá of Varáhamihira (d. 587 A. D.) there is mention of iron and mercury among the aphrodisiacs and tonics; and this