NEW TRAMWAY LOCOMOTIVE.

Otago Witness, Issue 1466, 3 January 1880, Page 20

NEW TRAMWAY LOCOMOTIVE.

The interest everywhere evinced in the tramway system as a means of locomotion ia very considerable, as is evident from the schemes formed not only for extending it in towns, but for introducing it into wide districts. One of the chief considerations of that interest is directed to finding a suitable substitute for horses as a draught power, for tbe working of the tramways by means of horses has been found not only inconvenient but expensive ; and those who are concerned in these undertakings, whether as proprietors or as acting on behulf of the public, have lately contemplated as likely their being able to dispense almost altogether with hordes,, and to put in their place steam-engines so constructed as to be perfectly safe as an important portion of the street traffic, and entirely free from any cause of annoyance or nuisance by noise or the discharge of smoke aud steam. Engines specially designed and constructed for the purpose have already been in use for some time in continental towns and various parts of the world, including some places in England, and they will probably before long everywhere supersede horses on tramways. Recently, Messrs R. and W* Hawthorn, of Newcastle, imported a tramway engine — Browne's patent — which has been at work on the Continent, and which is to be tried on the lines on thejNorth road ; and now Messrs Black, Hawthorn, and Co. , have designed and manufactured an -admirably compact engine, which possesses the negative qualities that are insisted upon by the Board of Trade. Last week the firm invited the several Corporations of Tyrieside and Sunderland to inspect a trial of the new engine, and the invitation was largely responded to, about 120 gentlemen being present. The engine has been designed with a view to secure the greatest attainable economy in working, viz., in the consumption of fuel, water, oil, maintenance, &c. The compound system has been adopted for the engine to secure the greater benefits ■derived by working the steam expansively, and thus attaining economy in the use of steam and fuel. A special feature in it is the employment of an improved condenser, patented by Messrs Black and Hawthorn,' for condensing the exhaust steam, and which at the same time admits of the same condensing water being used *>ver. and over again continuously, thus •obviating the necessity for" taking in new supplies of water for the condensing operation, which is no small expense and trouble in the working of some condensing tramway engines. The simple and substantial manner in which the whole engine has been got up, also the fact that it has been constructed both in material ■and workmanship equal to best locomotive practice, will go far to keep down expenses "for repairs. The cylinders are placed between the frames, and are seven inches and .12 inches diameter respectively, with a piston stroke of 11. The engine is direct acting, and has four wheels 24 inches in diameter, all coupled. The boiler is of the usual locomotive type, made extra strong, having copper firebox and brass tubes, with a working pressure of 1501b per square inch. The fire grate is arranged to burn coke with the aid of a natural draught of the chimney. The exhaust steam from the lowpressure cylinder is admitted into a tank having a great number of small tubes exposed to the air, and which may be called a condenser; it is placed above the boiler. The condenser when in working order is nearly full of water. The exhaust steam when entering it is condensed, and at the same time, by a cone jet arrangement, it causes the contents of the condenser to be circulated, and thereby to be cooled by coming in contact with the large exposed radiating surface. The engine was tried in steam for four hours consecutively, without any fresh water having to be supplied, and would have gone on much longer if it had been desired. There was no appearance of steam nor smoke, and the engine waa practically noiseless during the whole trial, thus fulfilling the Board of Trade requirements in those respects. The engine is short and 'compact, and runs very smoothly and steadily. It can be worked from either end, the driver sitting in front, having ah unobstructed •view before him. The engine is fitted with a very effective steam brake, which can also be worked by hand, and is •capable of bringing the engine to rest in a distance equal to its own length, or 10 ft., when travelling at a speed of six ■or seven miles an hour. All the working parts of the engine are hidden from view, and carefully protected from dust and dirt. A neat awning is provided for the driver. The engine will be fitted with a speed indicator and governor. It is expected that in a short time the engine will be tested on the Newcastle tramways. It is expected to take two loaded tramoars up a gradient of 1 in 80. Messrs Black, Hawthorn, and Co. hope to be able to effect many improvements in detail, which experience may suggest. The company seemed highly pleased with a trial which was very successful, and which apparently convinced all that it effectually disposes of every objection that may be raised to the employment of a locomotive engine on the tramway lines. — Iron.

The Appennine Railway reaches its highest point at an elevation of 617 metres above sea-level ; the Black Forest Railway ascends ■to 850 metres, the Semmering line to 890, and the Cauoisus line to 975 metres.

An English paper asserts that nineteentwentieths of the people in London have to go without fresh vegetables.