The front page of our present Number exhibits an external elevation of this engine and its tender; but on a scale one-half less than our engraving of "The Novelty." The furnace A is two feet wide by three feet high, the boiler B is six feet long and three feet in diameter. The furnace like that of "The Novelty" has an external casing between which and the fireplace there is a space of three inches filled with water and communicating with the boiler. The heated air from the furnace is circulated through the boiler by means of twenty-five copper pipes of three inches each in diameter, which have their termination in the tall chimney C. FG are safety-valves; HH the steam eduction pipe. D one of the steam cylinders which have an angular inclination towards the wheels, and embrace like two arms the boiler between them. E one of the connecting-rods which give motion to the wheels; a, the slide of the piston of the cylinder seen in the engraving; and o, one of two escape-pipes. M is the part of the tender appropriated to the carriage of fuel; N the water-cask.

The performances of this engine indicate a very abundant and well sustained production of steam; but the extent of surface which it has been found necessary to expose to the heat, in order to obtain that effect, the great size of all the parts, and the quantity of fuel required — are faults which even a still more copious generation of steam would scarcely compensate. It is not by means of its heavy weight alone that such an engine would operate injuriously on the rails. The chimney from its great height — a height necessary to obtain that draught which in "The Novelty" is produced hy means of the air-forcing apparatus — gives a swaying motion to the engine from side to side; and the rails have thus a lateral as well as a longitudinal force applied to jerk them out of their places.

We observed in our first notice of this engine, (No. 322, p. 115) that it exhibited but a very partial fulfilment of the condition that it should "effectually consume its own smoke." As far as regards its performances on the first day of the competition, this statement was perfectly correct. It is only fair however to state, that in its more recent exhibitions there was scarcely any emission of smoke perceptible. We have heard that on the first day there was an accidental intermixture of coal with the coke; a circumstance which, if true, would sufficiently account for the appearance of smoke on that occasion.

(To be continued ir our next.)