The Rowan tram-car consists of a body 31 feet long and 7 feet wide, resting on a two-wheeled bogie behind and on a four-wheeled bogie in front, this front bogie being the motor, and the whole has the appearance of a long railway carriage, somewhat in the form of an omnibus with a platform at each end, of which the front platform is occupied by the engine.  It requires, therefore, either a turntable or a triangle at the end of the line, so as to enable it to reverse its direction.

This motor is a steam engine of light and simple form, supplied with steam from a water tube boiler with very perfect combustion, so that no smoke escapes.  The boiler is somewhat on the principle of a Shand and Mason boiler; it is so built that It can easily be opened and every part of the interior examined and cleaned.

The peculiarity of the Rowan motor is the simplicity of the attachment of the engine to the carriage, and the facility with which it can be detached when required for cleaning or repair, viz., in five or six minutes.

The steam can be got up in the engine with great rapidity if a change of engine is required.  When, however, the engine is detached, the carriage loses its support in front, and is therefore not serviceable.  When necessary, the combined motor can draw a second ordinary carriage.

The motor by itself occupies a length of 9 ft. 8 in.  It has two horizontal cylinders; the four wheels of the bogie are coupled, and between the wheels the sides of the framing are rounded to allow two vertical boilers to stand.  These boilers have vertical tubes for the water, which are joined together at the top by a horizontal cylinder.  Each boiler, with its covering, is 1 ft. 9 in. in diameter.  The boilers stand 1 ft. 9 in. apart, thus affording space between them for the motive machinery, including the pump.  The crank axle is behind the boilers.  The levers, the injector, the access to the fire-box, a pedal for working the engine brake as well as a screw brake for the carriage, are all in front.  The brakes act on all six wheels, are worked by the driver, and the whole weight of the engine, car, and passengers being carried on these wheels, the car can be stopped almost instantaneously; and as over two-thirds of the entire weight of the car and passengers rests on the four driving wheels; there is always sufficient adhesion on all reasonable inclines, and the adhesion is augmented as the number of passengers carried increases.  Hence this car is adapted for lines with heavy grades.

A small water tank is attached to the framing; two small boxes for coal or coke, with a cubic capacity of about 31/2 feet, are attached to the plate in front of the bogie.  The covering of the boilers is in two parts, which are put on from each side horizontally, and screwed together in the center.  The removal of the upper part enables the tubes to be examined and cleaned.  The draught is natural; the base of the chimney is 3 ft. 2 in, from the grate; the height of the chimney is 5 ft. 2 in.