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had a very good fusion, but which, from a small blow of ahammer upon a steel anvil, fell into powder. Mr. Macquerappears therefore, in this utmost effort, to have producedno other effects than those which I had obtained; and histrials concur with the others in proving, that the best ofthe common furnaces, and melting vessels, will themselvesmelt sooner than the platina included in them.

VI. Platina exposed to the jire in contadl with the burning fuel,

As the power of fire, upon metallic as well as earthybodies, is remarkably promoted by the immediate contactof the burning fuel, and the impulse of air upon the sub-ject, platina was exposed to its action in those circumstances.Mr. Scheffer seems to regret that he had not some poundsof the metal for a trial of this kind, but the process may bemanaged in such a manner, that a very little quantity canbe made to suffice.

A crucible, having a bed of charcoal in it, was laid onits fide among the fuel, in a good blast-furnace, with itsmouth towards the nose of the bellows; and on the char-coal were spread four ounces of platina. The fire was ve-hemently urged for above an hour; during which an in-tense white flame passed through the crucible, and issuedat an aperture made for that purpose in the end. Greatpart of the crucible was vitrefied; but the grains of platinaonly superficially cohered and became brighter, withoutseeming to have at all softened or altered their shape.

The experiment was several times repeated and varied:common lalt, whose fumes promote the vitrification of thecrucibles themselves, was thrown on the fuel before themouth of the vessel, and its fumes strongly impelled uponthe platina: the lumps of platina which had undergonethe preceding operations, were dropt, before the nose otthe bellows, into violently-excited charcoal and sea-coal

fires,