main deck.
The "Bruce" is further fitted with a complete installation of electric
lighting, together with an electric search light; has Lord Kelvin's
deep sea sounding apparatus and compasses, also Caldwell's steam
steering gear and winches, Weir's evaporators and pumps. Alley and
McLellan's feed water filters, and Howden's forced draught. She is
steam heated throughout, and in every detail of the sanitary
arrangements the health and comfort of the passengers have been
attended to. Six lifeboats, having accommodation for 250 people, are
hung in davits. When fully laden she carries 350 tons of cargo in her
holds and 250 tons of coal in her bunkers.
The contract speed for the "Bruce" was 15 knots--and to obtain this
Messrs. Inglis fitted her with triple-expansion engines, which we
shall illustrate in another impression, having cylinders 26 inches, 42
inches and 65 inches in diameter, with a 42 inch stroke. Steam is
supplied from four boilers loaded to a pressure of 160 pounds per
square inch. When on the measured mile a mean speed of about 151/4 knots
was obtained with an indicated horse power of 2200, the engines
running at 90 revolutions per minute.
The vessel has arrived safely at Newfoundland, having performed the
voyage at a mean speed of very little under 15 knots, a most
satisfactory performance. She has been running some little time on her
route and been giving most satisfactory results.--We are indebted to
London Engineer for the cut and description.
* * * * *
HEAT IN GREAT TUNNELS.
One phase of the construction of tunnels through the Alps was recently
discussed by M. Brandicourt, secretary of the Linnaean Society of the
North of France, in the columns of La Nature. He showed that only a
few thousand feet below the eternal snows of that region so high a
temperature may be found that workmen can scarcely live in it. Nearly
all of the other difficulties encountered in those enterprises had
been foreseen. This one was a great surprise. It shows how the
interior heat of the earth extends above sea level into all great
mountainous uplifts on the earth's surface.
During the tunneling of Mont Cenis, says M. Brandicourt, the
temperature of the rock was found to be 27.5 degrees C. (81.5 degrees
F.) at about 5,000 meters (16,000 feet) from the entrance. It reached
29.5 degrees (86 degrees F.) in the last 500 meters (1,600 feet) of
the central part. The workmen were th
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