gether. Brake blocks of cast iron are used in some cases, and are found to be preferable to wood. The brakes are set by winding a chain in connection with them on an upright barrel having a handwheel at the top. In cases of emergency it has been proposed to work the brakes by a friction wheel which may be instantly pressed down on the driving wheel of the engine. A cord is carried along the top of every carriage of the train to a large gong bell placed on the engine. This cord is formed in lengths equal to the length of a carriage, and the pieces are connected together by metal snaps. A small shaft led along the top of each carriage, with square or triangular ends and sockets and universal joints would be an equally simple arrangement. It is not found practically in America that there is any trouble in connecting the cord to the new carriages when a change in the carriages takes place.

The American railway carriages are of much larger dimensions than those employed in this country. The bodies are commonly made about 45 ft. long, 9 ft. wide, and 7 ft. high. The carriages are open from end to end, and at the end doors are placed, opening upon platforms protected by railings, and establishing a passage between one carriage and the next adjoining. From the platform stairs descend, by means of which passengers enter or leave the carriages. The seats are ranged on each side of a central passage; and the backs of the seats are made to turn either way. On the roof of the car

riages ventilators are placed; and there is a stove to warm the carriage in winter, and a supply of drinking water. To prevent the dust from arising, a canvas curtain has been introduced outside the wheels on some lines, extending from the carriage floor to the ground, whereby the dust is prevented from being sucked up by the motion of the train. In other cases jets of water propelled by a centrifugal pump, moved by a friction roller resting on one of the wheels, have been introduced in an air space on each side of the carriage, through which the air is admitted; and the air is thus cooled and freed from dust by the same operation.

The carriage rests at each end on a truck or bogie, the wheels of which are as far apart as the distance between the rails, so that the plan of such a truck forms a square. India rubber springs have been tried, but the result has not been satisfactory; and plate or volute springs are now usually employed.

In all the American locomotives, the internal fire box is considerably smaller at the top than at the bottom, so that the sides are much inclined, whereby the escape of the steam from the surface of the metal is facilitated, and the overheating of the plate prevented. The fire boxes are almost universally of iron. The tubes of the boiler are generally of copper-few iron or brass tubes being in use, except that in engines using anthracite coal iron tubes are used to diminish the wear caused by the hard particles of coal carried up by the draught, and which

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copper cannot so well withstand. The general proportions of the American locomotives do not differ materially from those prevailing in England. On the whole, however, the blast pipes require to be smaller, and the draught more intense for engines burning wood, to maintain sufficient vividness of combustion; and the disposition now is to place the tubes farther apart than formerly, as has been long found in this country to be expedient. In some engines it has been found that an increased supply of steam was obtained by removing some of the central tubes; and the tubes are never placed closer than of an inch apart.

There is frequently a blast pipe from each cylinder. These pipes terminate at about the level of the lowest row of tubes, and suspended over them is a pipe entitled a petticoat pipe,' about 8 in. in diameter, which reaches nearly to the base of the chimney. This pipe being generally made conical, has a petticoat configuration. The object of this arrangement is to equalise the draught through the different rows of tubes, as when the blast pipe is carried up to the level of the top row of tubes, the greatest draught will be through them.

STANDARD FORMS OF ENGLISH

LOCOMOTIVES-BROAD

GAUGE ENGINES.

The most powerful class of engines constructed for the broad gauge is that of the Great Britain and