. & J. Stuart & Clydesdale, Limited, and
the results have been such as to induce him to introduce these into
vessels recently built by the company. It may be stated that the pipes
only burst at a hydraulic pressure of 3,000 lb. to the square inches.

The Tynwald was tried on the Clyde about a month ago, and on two runs
on the mile, the one with and the other against the tide, the mean
speed was 19.38 knots--the maximum was 191/2 knots--and the indicated
horse power developed was 5,200, the steam pressure being 160 lb., and
the vacuum 28 lb. Since that time the vessel has made several runs
from Liverpool and from Glasgow to the Isle of Man, and has maintained
a steady seagoing speed of between 18 and 19 knots.--_Engineering._

* * * * *

THE TREATMENT OF REFRACTORY ORES.

Mr. Jas. J. Shedlock, with the assistance of Mr. T. Denny, of
Australia, has constructed on behalf of the Metallurgical Syndicate,
of 105 Gresham House, London, an apparatus on a commercial scale,
which, it is said, effects at the smallest expense, and with the best
economical results, the entire separation of metals from their ores.
In treating ores by this process, the stone is crushed in the usual
way, either by rolls or stamps, the crushed ore being conveyed into an
apparatus, where each atom is subjected to the action of gases under
pressure, whereby the whole of the sulphur and other materials which
render the ore refractory are separated. The ore is then conveyed into
a vessel containing an absorbing fluid metal, so constructed that
every particle of the ore is brought into contact with the metal. For
the production of reducing gases, steam and air are passed through
highly heated materials, having an affinity for oxygen, and the gases
so produced are utilized for raising the ore to a high temperature. By
this means the sulphur and other metalloids and base metals are
volatilized and eliminated, and the gold in the ore is then in such a
condition as to alloy itself or become amalgamated with the fluid
metal with which it is brought into close contact. The tailings
passing off, worthless, are conveyed to the dump.

The apparatus in the background is that in which the steam is
generated, and which, in combination with the due proportion of
atmospheric air, is first superheated in passing through the hearth or
bed on which the fire is supported. The superheated steam and air
under pressure are then forced