S. B. Christy— Genesis of Cinnabar Deposits. 463 
of dry distillation, ee as the effect of heat in presence of 
d if t h 
water. And if the temperature were great enough to have 
volatilized ne it is probable that these much more vola- 
tile hydrocarbons of the original organic matter would have 
disappeared, and we should have anthracite or — instead 
of bitumen, as we do in most of the cinnabar deposit 
In addition to this we have shown that the ‘oulphide of mer- 
cury at comparatively moderate temperatures is soluble in solu- 
tions of the alkaline sulphides, that increase of pressure aids 
rather than retards this solution, and that cinnabar is deposited 
‘from such solutions in the crystallized form when the tem- 
perature and pressure are slowly lowered. We have shown 
that by adding sulphydric acid to the mineral spring water, 
now existing in the neighborhood of one of the most noted of 
dap deposits, = were enabled to produce the same effects. 
arious reasons, which it is unnecessary to state here, it is 
woth: that this 8 se once —_— sulphydric as well as 
carbonic acid, and we have, consequently, in the case of the 
New Alm aden mine, sufficient cause at least for the | 
gad gases. Such a mixture of geen sotihiaes with min- 
i rib 
easily reproduced by any o of these methods. No other theory 
so well accounts for the intimate mixture of the two varieties ; 
for the amorphous product produpos by suddenly cooling the 
vapor presents an pai 9 appearance. 
inally, the almost universal peat eh of these deposits in 
metamorphic rather feast in - ipieous rocks, vipa well with 
the theory that these deposits as they exist in situ 
result of the action of solutions of alkaline parabens containing 
also alkaline su 
There are still many other points of interest in this connec- 
tion which are difficult to understand. Such, for sap are 
inexplicable upon either hypothe 
University of California, Berkeley, Dec., fe 
