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hitherto called Anthophyllite, and so given by Prof. Dana, 
was shown to be a new variety of Tremolite. 
He gave also the result of an examination of a rod of glass, 
four feet in length and two inches in diameter, formed by a 
stroke of lightning falling upon a bank of very white sand, 
near Fayetteville, N.C. The strangely-contorted fragments 
of the rod were silex, perfectly fused and almost pure. The 
only foreign body present was a trace of iron. Some of the 
sand in immediate contact with the fused silex was stained 
yellow by the same body. It remains to be determined 
whether the iron contained in the fulgurite, existed original- 
ly in the sand composing the bank, or was in any way present 
in the lightning discharge. 
Mr. WILLIAM FALKE read a paper on Physical and Vital 
Theories of Fermentation. 
Two fundamentally-different theories exist, to explain the 
phenomena of fermentation, one a physical or strictly azotic. 
theory, and the other the germ theory. The prevailing 
opinion, since the discovery of the yeast plant in 1837, by 
De la Tour, has been that ferments are living organisms, and 
that fermentation depends upon an exercise of the vital force. 
On the other hand, Liebig and others have sought to explain 
fermentation by so-called presence-action, on the ground that 
the ferment, being unstable, readily breaks up, and in so do- 
ing communicates molecular motion to the body in which 
the fermentation is effected. The necessity of the presence 
of oxygen is also a disputed point, and one of great impor- 
tance. Mr. Falke spoke of the exclusiveness of the vital 
theory, and proceeded to argue in favor of the physical view, 
strongly maintaining the doctrine of spontaneous generation. 
He quoted numerous writers who support this view, and 
described some of his own microscopic observations on the 
Torula cerevisve. 
Dr, ENDEMANN remarked that there are several varieties 
of Torula, with different capacities of fermentation, and spoke 
of the weighty evidence of Prof’ Wyman’s experiments on 
the side of the germ theory. 
