Engineers and Mechanics Encyclopedia 1839: Railways: William Harland

Two days after the last-mentioned contrivance obtained the privilege of the Great Seal, Dr. Harland, of Scarborough, also passed a patent for what may be denominated a steam phaeton, from the figure of the carriage given in the specification, of which the is a sufficient resemblance.

"The improvements contemplated by Dr. Harland, are stated, in his specification, to consist, first, in the construction of a boiler, by which a very large surface of the fire and flue will be placed in contact with the water, for the rapid production of steam; secondly, in the employment of a condenser, which, by its extensive surface, shall condense the steam by the influence of the atmosphere; thirdly, in a mode of fixing the working cylinder, without allowing it to vibrate in hollow arms or trunnions.

a-a represents the bed of the carriage; b1 and b2 the boiler, composed of two double cylinders, b1 containing the fire-grate and ash-pit, and the cylinder b2 containing another double cylinder; so that there are, in fact, three double cylinders, each full of water, and communicating with the reservoir and steam chamber c, which must be of sufficient capacity to keep the boilers supplied during the period of one stage, so that they be always full: d is the chimney; e a damper, by which the boiler b2 may occasionally be withdrawn in part front the action of the fire; f is a spherical vessel on the top of the reservoir, the object of which is to prevent the water thrown up with the steam being driven with the steam into the pipe g, which conveys it to the working cylinder h; this cylinder is secured horizontally to the bed of the carriage, and having guides extending from end to end, in which side-rods, attached to the cross on the piston rod, move, and carry with them the connecting rod k, which turns the crank l; this crank has on its axis a toothed wheel m, and revolves on bearings placed on the bed of the carriage. The carriage receives its impulse from the engine upon the hind wheels; the axis of these carry small tooth-wheels n, which gearing into m, receive their motion, and thereby turn round the naming wheels. Arrangements are made by the patentee for throwing the toothed-wheels m and n out of gear, and bringing into operation another pair of wheels on the same axles, when additional power is wanted; but the apparatus for this purpose is not brought into view in the engraving, to prevent confusion. At o an eduction pipe, leading to a series of tubes p, which are denominated the condensing chambers, and may be used, either alone or in conjunction with water, to condense the steam on leaving the cylinder; is a pipe for conducting the hot water and uncondensed steam into a globular vessel r, connected with an additional series of condensing pipes s, of an annular form, and connected with each other by short pipes; t, is a pipe for returning the condensed water from r to the boiler, by the aid of a small force pump, v is a forked rod attached to the steering wheel x, and descending into holes is the arms of the fore wheels, and having liberty to move up and down, according with the inequalities of the road; the vertical standard, upon which the upper steering wheel s is fixed, also forms the centre of motion to the arms of the fore wheels, and is thereby made to direct them in their course.

"The advantages contemplated by Dr. Harland in these arrangements, will, we fear, not be realised. In the construction of the boiler, there is nothing upon which we can congratulate him. The attempt to condense the steam has been long since abandoned by those who have had the most experience on the subject; it is evidently impracticable to carry sufficient water to effect even a tolerable condensation; the conducting power of the air is much too slow for the abstraction of the heat, and it should be considered that the air which is liberated from the boiling water, would require a pump to draw it off; which would add complexity to the machinery.

“With regard to the mode of fixing the cylinder, it differs but little from that adopted by Mr. Gurney. The mode of communicating the power to the wheels is extremely defective, for it will be observed, that the driving toothed-wheels m are (in effect) mounted upon the springs of the carriage, above the driven toothed-wheels n, by which means they will be continually liable to be thrown out of gear by the motion of the carriage, and the teeth will be liable to break from the same cause."

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