of the water, the whole being precipitated down a series of
falls, at each of which it is caught up again by new sluices of timber,
lined like the first, and so onward and downward many hundreds of feet
until the level of the river is reached, at a distance of about a half
mile or more from the mouth of the first tunnel.

At each of these new falls of 25 to 50 feet the process of comminution
begun in the first shaft is carried on, and a fresh portion of gold
obtained. Rude as this plan of saving gold appears to be, more gold is
procured by it than by any other method of washing yet devised for this
process of work, and the economical advantages obtained by it cannot be
surpassed, as it would be impossible to handle such vast quantities of
material in any other way, and we can compare the cost of washing and
handling a cubic yard of auriferous gravel by it as follows:

Dollars.
By manual labor with the pan 15.00
" " with rocker 3.75
" " with the long tom .75
By the hydraulic process .15

But this process, even if effective or profitable as a mining operation,
may be prejudicial to the interests of the general public, if conducted on
a large scale, as the vast quantity of material which it so suddenly
removes is merely shifted into the shallows beneath, to be redistributed
by every freshet to points lower and lower down until it reaches the
sea-coast, creating bars at the mouths of rivers in its course, and
changing the hydrography of harbors--as it has done with the Bay of San
Francisco by its silt.

The hills behind, torn up and washed by the gold miner, are abandoned as
desolate and irredeemable; and the costly canals, constructed with
peculiar conveniences for mining purposes, eventually fall into disuse
from being too expensive to maintain or alter for general agricultural
uses.--_Journal of Science._

* * * * *

THE TREATMENT OF CHOLERA.

From the host of remedies and suggestions that are now deluging the
European medical press, we select the following from Dr. Henry A. Rawlins,
in the _London Med. Times_, July 12. 1884:

The man suffering from cholera has been suddenly deprived by diarrhoea of
an enormous quantity of the fluid part of his blood. This loss is one of
simple transudation, increasing as the powers of life decrease. This
_sudden_ loss