OBSERVATIONS, 
7 ? 
§ 7 - 
Thefe properties fhew evidently the 
acid of tungften or wolfram to be me¬ 
tallic. If the fuppofition be true, that 
every fubftance of a metallic nature is 
capable of affording a regulus, we fhould 
exped to obtain one from this acid. 
Neverthelefs, Mr. De Luyart is the only 
perfon who has fucceeded in producing 
a regulus. My experiments have hi¬ 
therto failed, though I have attempted 
the redudion by different methods and 
different fluxes, both in common melt¬ 
ing furnaces, and even in thofe ufed for 
making porcelain at Berlin. 
I juft mention, that in thefe experi¬ 
ments I always made ufe of the yellow 
acid of wolfram ; for I fhould fear that the 
metallic globule obtained from the white 
unpurified acid, might be produced by 
a portion of iron and arfenic combined. 
