,
and passing through the volute, B, evaporates the salt water contained
in the chamber, C; the vapor thus generated passing through the pipe,
D, into the volute condenser, E, where it is condensed. The fresh
water thus obtained flows into the filter, from which it is pumped
into suitable drinking tanks.

[Illustration: VOLUTE DOUBLE DISTILLING APPARATUS.]

The steam from the boiler after passing through the volute, B, is
conveyed by means of a pipe to the second volute, H, where it is
condensed, and the water resulting is conveyed by means of a pump to
the hot well or feed tank. The necessary condensing water enters at J
and is discharged at K. The method of keeping the supply of salt water
in the evaporator at a constant level is very efficient and ingenious.
To the main circulating discharge pipe, a small pipe, L, is fitted,
which is in communication with the chamber, M, and through this the
circulating sea water runs back until it attains a working level in
the evaporator, when a valve in the end of pipe, L, is closed by the
action of the float, N, the regulation of admission being thus
automatic and certain. The steam from the boiler can be regulated by
means of a stop valve, and the pressure in the evaporator should not
exceed 4 lb., while the pressure gauge is so arranged that the
pressure in both condenser and evaporator is shown at the same time. A
safety valve is fitted at the top of the condenser, and an automatic
blow-off valve, P, is arranged to blow off when a certain density of
brine has been attained in the evaporator. The "Esco" triple pump
(Fig. 3), which has been specially manufactured for this purpose, has
three suctions and deliveries, one for circulating water, the second
for the condensed steam, and a third for the filtered drinking water,
so that the latter is kept fresh and clean.

The condenser and pumps are manufactured by Ernest Scott & Co., Close
Works, Newcastle on Tyne, and were shown by them at the late
exhibition in their town.

* * * * *

IMPROVED CURRENT METER.

Paul Kotlarewsky, of St. Petersburg, has invented an instrument for
measuring or ascertaining the velocity of water and air currents.

Upon the shaft or axis of the propeller wheel, or upon a shaft geared
therewith, there is a hermetically closed tube or receptacle, D, which
is placed at right angles with the shaft, and preferably so that its
longitudinal axis shall intersect the