Engineers and Mechanics Encyclopedia 1839: Railways: W. Carpmael
A variety of novel combinations of mechanism for steam carriages were patented on the 6th December 1835, by Mr. W. Carpmael, of Crawford-street, as the agent of a French gentleman.
In the space which we can devote to notice it, it would be quite impractical to convey an intelligible idea of the numerous ingenious contrivances the specification sets forth; we shall, therefore, merely state, that the boiler consists of two parallel rows of large vertical tubes for the water, so placed in a quadrangular case, as to divide it into three compartments, the middle one of which is the largest.
In this middle chamber is put the fuel, coals; and in the two small chambers in the other sides of the two rows of tubes, is put another kind of fuel, coke. The combustion of the coals is excited by a fan-wheel, placed under the grating of the coal chamber, and the smoke and other inflammable matter that escapes from this fire-place is conducted between the tubes and over the coke fires, by which arrangement the smoke and carbonaceous matters will, it is fairly presumed, be inflamed, and the caloric thus extricated be beneficially employed in the generation of steam.
The steam chambers, consisting of capacious horizontal tubes, close up the tops of each of the furnaces; and the steam is conducted through regulating valves and pipes to the engines situated in the bed of the carriage frame.
Note: W. Carpmael was a Patent agent.