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cury is directed to be added. I have continued thetrituration of an amalgam of gold, almost incessantly, formore than a week, and afterwards recovered the goldentire.

Kunckel imagines, that when glass is tinged red byCaffius’s precipitate or other preparations of gold, theparticles of the metal are not barely dissufed through theglass, but resolved into their elementary parts, so as nolonger to be reducible into gold again. He might indeedfail of recovering the gold; but though no means wereknown of separating so small a propotion of it from solarge a quantity of vitreous matter, it surely could notfollow that the gold was destroyed.

Some other processes, proposed for the destruction ofgold, have been already taken notice of. It has beenshewn, that the vehement heat, collected in the focus oflarge burning glasses, and the long continued action of agentle heat, do not, so far as can be judged from the factsas yet known, make any real change in it; and that themuch boasted volatilization of gold does certainly notdestroy it, since the volatilized gold may with eafie berestored to its fixity and all its former qualities.

Upon the whole, both the producibility and destructi-bility of gold continue still problems in chemistry. Iknow of no experiment from which the possibility ofeither can be inferred; and to demonstrate their impost!-bility is beyond the reach of experiments.

But though those, who have laboured the most ardentlyin these pursuits, instead of acquiring, have generallyexhausted riches,, and may on good grounds be presumedto have missed of their principal aim; yet justice requiresus to add, that their labours have not been altogetheruseless, and that many valuable discoveries, relative to.different subjects, have resulted from their enquiries. It

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