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slightly, and being laid again in the balance, it rather out-weighed its -former counterpoise which had been lest inthe scale. From this experiment,which was two or threetimes repeated with the same event, I concluded, in thefirst: paper, published in the Philosophical Transactions,that platina does not lose of its weight in the fire :Mr. Marggraf and Mr. Macquer have since found, that itnot only does not lose, but really gains weight, and thatwhen the fire is long continued, the gain is very consi-derable.

8. Mr. Marggraf put two ounces of crude platina in ascorifying dish under a muffle, and kept up a strong firefor two hours, stirring the platina at times with an iron rod.He observed that no fumes arose; that when grown cold,the metal looked like shavings of lead run together, butblacker and without metallic lustre; and that its weightwas not diminished but increased, for it weighed twoounces and ten grains, or one part in ninety-six more thanit did at first.

9. He repeated the experiment with one ounce of pla-tina, in a covered crucible, placed on a proper support, ina melting furnace,which, by means of a long pipe for con-veying in the air under the ash pit, and a long narrowchimney on the top, gives the strongest fire of all the fur-naces in his elaboratory. The fire being kept up in itsgreatest vehemence between three and four hours, the pla-tina was found sticking together but not melted, andweighed five or nearer fix grains, that is near one part ineighty, more than at first. He takes notice that the grainswere pretty easily separated by a blow of a hammer; thatthose in the internal part of the lump were whiter than atfirst, but that they were still in their original form ; andthat some of them bore to be flattened on the anvil.

Ooo 10. Mr.

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