44 ON THE CINNABAR MINES OF UPPER CALIFORNIA. 
In the preparation of collodion it is indispensable to avoid 
the presence of water, as this renders it less adhesive ; hence 
the ether as well as the alcohol should be pure and rectified. 
The parts to which the collodion is applied should be first 
thoroughly dried, and no water allowed to come in con- 
tact with them until all the ether is evaporated. — London 
Medical Gazette. 
ART. IX.— THE CINNABAR MINES OF UPPER CALIFORNIA. 
By the Rev. C. S. Lyman. 
The mine of New Almaden is situated a few'miles from 
the coast about midway between San Francisco and Mon- 
terey, and in one of the ridges of Sierra Azul mountain. 
The mouth of the mine is a few yards down from the sum- 
mit of the highest hill that has yet been found to contain 
quicksilver, and is about 1200 feet above the neighbouring 
plain, and not much more above the ocean. This hill ex- 
fends longitudinally in a north-westerly direction, decreas- 
ing in height ; and in various parts of it, for several miles, 
traces of the ore have been found, and some openings have 
been made which promise to be valuable. This range of 
hills consists of a variety of rocks, which I have not yet 
had an opportunity properly to study. The prevailing one 
is a greenish talcose rock, which seems to embrace the bed 
of ore at the New Almaden mine both above and below. A 
specimen from the rock immediately contiguous to the ore 
is contained in the box. The ore is interspersed through a 
yellow ochreous matrix, which forms a bed 42 feet in thick- 
ness, dipping northwesterly at an angle of about 45°. The 
richest ore is at present found in the upper part of the bed, 
the poorer ores being taken from the lower portion. 
This mine, known to the aborigines from lime immemo- 
