78 
FIRST REPORT -1831. 
Mr. Johnston gave an account of the Metal Vanadium and 
its ores. 
He stated that this metal was first observed, though without 
being distinctly made out, by Del Rio in Mexico 25 years ago, 
and afterwards rediscovered by Seftstrom, and nearly at the 
same time by himself, about the end of last year. He exhibited 
and described the mineral from Wanlock-head, in which he found 
it, detailed the process for extracting it, enumerated its most 
interesting properties when in the metallic state, and the charac¬ 
ters by which in all its states it may be distinguished from Chro¬ 
mium, the only other metal with which the analytical chemist is 
likely to confound it. He exhibited various compounds and 
salts of the metal, among which were some beautiful crystals of 
Vanadic Acid, which were transparent, of a brown colour by 
transmitted light, but reflecting a purplish tint. They were in 
the form of flat prisms of a high degree of lustre, and had been 
ascertained by Dr. Brewster to possess a refractive power ap¬ 
proaching that of the diamond, to have at least one axis of double 
refraction, and to belong to the prismatic system of Mohs. 
Mr. Witham read a paper on the general residts of botanical 
investigation concerning the character of the Ancient Flora, 
ivhich by its decomposition has furnished the materials of coal- 
seams. He described the discoveries which the art of slicing 
and polishing the fossil stems of plants had enabled him to make, 
concerning the internal structure of these large coniferous trees 
which especially abound in the lower part of the Carboniferous 
Series of Berwickshire; and stated that Geologists are now 
agreed that the plants of these ancient periods are of more di¬ 
versified and complicated types than a distinguished foreign 
writer supposed. 
The following Notice of a fact observed in the tor refaction of 
Yellow Copper Pyrites at Amlwch, in Anglesey, by Dr. Henry, 
was read by the Secretary. 
“ When on a visit, a few years ago, to the Copper-Mines and 
Works at Amlwch in Anglesey, a fact was mentioned to me by 
an intelligent superintendent of the processes carried on there 
(Mr. Joseph Jones), which struck me to be interesting and cu¬ 
rious. The poorer part of the ore (a native mixture of yellow 
copper pyrites with so much foreign matter as to contain only 
about 5 per cent, of copper,) is roasted in kilns on the spot, in 
order to expel a considerable part of the sulphur. The com¬ 
bustion, after the kiln has been once lighted, is supported by 
