We give engravings of the Churchill, a vessel lately built to the order
of Mr. Walter Peace, London agent to the Natal Harbor Board, by Messrs.
Hall, Russell, and Co., Aberdeen. She was designed by Mr. J.F. Flannery,
consulting engineer to the Board, for special service at Natal. The
Churchill has been constructed so as to be capable of towing into or out
of harbor over the bar in any weather, of acting as a very powerful fire
engine, of carrying a large amount of fresh water for the use of other
ships, of landing troops from transports which the harbor is too shallow
to admit, of recovering lost anchors and cables, of which there are a
large number off the coast, and of acting in time of need as a torpedo
or coast defense vessel; she was launched on the 16th August, and is
likely to fulfill all these requirements.
[Illustration: THE NEW STEAMSHIP CHURCHILL.]
The principal dimensions of the vessel are: Length between
perpendiculars 115 feet, breadth, extreme, 22 feet, depth of hold 11
feet, and maximum draught with full bunkers 7 feet 6 inches. There are
four water-tight iron bulkheads forming five compartments; the stern is
built very full to protect the propellers. Accommodation is arranged on
deck for the captain aft with two spare berths, mate and two engineers
amidships, while six white hands will occupy the forward forecastle, and
six Kaffirs the after one. For towing purposes she is fitted with one
main and two skip hooks secured to the main framing; towing rails are
placed aft, while bitts are put on one each quarter, will be seen by
referring to the deck plan.
The vessel is propelled by twin screws 6 feet 8 inches in diameter and
13 feet 6 inches pitch; these are of cast iron, have four blades, and
are driven by a double pair of compound inverted direct acting engines
(see Figs. 4 to 7) which are capable of developing 600 indicated horse
power, and whose cylinders are 19 inches and 34 inches in diameter with
a stroke of 2 feet. The condensers form part of the engine frame, and
have guide faces cast on for the crosshead shoes. They are fitted with
gun metal tube-plates, and each contain 516 tubes, 3/4 inch in diameter,
which have an exposed length of 6 feet 5 inches, and give a total
cooling surface of 650 square feet. The air and circulating pumps are
bolted to the back of the condensers, and are worked by levers from the
engine crosshead. Each engine has one feed and one bilge pump attached
to the air pump, and worked by the same lever. The plan of the engines
shows the pump arrangement very completely.
[Illustration: ENGINES AND BOILERS OF THE NEW STEAMSHIP CHURCHILL.]
The steam is supplied by two circular return tube boilers, 9 feet 6
inches in diameter and 10 feet long, with two furnaces in each. The
boilers, which are of steel throughout, except the tubes, are placed
longitudinally, and are fitted with two pairs of the Martyn-Roberts
patent safety valves. They have one steam dome between them. The total
heating surface is 1,700 square feet, the total steam space is 330 cubic
feet, and the working pressure 100 lb. per square inch.
The fire pump is a Wilson's "Excelsior," with 10 inch steam cylinder and
8 inch water barrel. This powerful pump is in a special compartment of
the fore hold, and will draw water from the bilge, sea, or either hold.
A steam windlass and a double-handle winch are on deck as shown. On
trial trip the engines of the Churchill indicated a maximum of 645.5
horse power, driving the vessel 10.495 knots per hour. The vessel is
remarkable for diversity of uses, for heavy engine power in a small
hull, and for general compactness of arrangement.--_Engineering_.
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