The front wheels of the carriage have separate independent axles, which turn horizontally upon a perpendicular column affixed to the fore framing. To guide the carriage, the steersman sitting in front turns a vertical spindle, the lower extremity of which carries two arms, that, by connecting rods attached to the separate frames of the two fore wheels, places them in the oblique direction required according to the curve of the ;cad. Each of the fore wheels being thus made to turn on its own centre, renders the action of guiding exceedingly easy.
The boiler is situated quite at the back of the carriage, and it is judiciously formed of a large cylinder, with a series of small tubes passing through it for the furnace flues. The lower part of the boiler is divided by perpendicular par titions, to prevent the water from leaving it uncovered during the ascent or descent of hills or inclined planes, or from the effects of other disturbing causes. To regulate the admission of the steam to the cylinders, and its exit therefrom, a species of three-way cock is employed; this is placed under the control of the guide, so that he may diminish or increase the quantity, and, by a further turn, shouldt be desired to stop the carriage suddenly, allow the steam to blow off. The steam from the last-mentioned cock next passes through a " distributing cock," and then enters each cylinder through passages on its trunnions, regulated by a cock fixed on each, which admits the vapour alternately on each side of the pistons, as the cylinders vibrate on their centres. The steam which is forced out of the work ing cylinders by the back stroke of the piston., is conducted through a pipe into a chamber, which the patentee calls the heating chest; wherein is also received the steam that blows off from the safety valve. There is a vessel connected with the boiler, containing a float, by means of which the amount of water forced into the boiler is regulated. This pump is worked by a lever, acted upon by a cam, that revolves upon the crank shaft. The water for the supply of the boiler is forced by the pump through a long winding tube in the heating chest, by which the temperature of the fluid becomes considerably heated before it enters the boiler. There is also a float in the boiler, connected with the water way of the pump, which, as the water rises in the boiler, closes the supply valve, so that if the pump continues in action, no more water can be injected, but it will be returned through the cold water pipe. There are two water tanks, one on each side of the carriage, next to the hind or propelling wheels, and between these tanks is the coal-hole.
The introduction of railroads and other facilities of transport has for many years past occupied the attention of the citizens and legislature of the United States of America, and every improvement made in that country of a decided or specious character, soon after makes its appearance here, under the pro tection of the great seal. Amongst the many ingenious men who have imported themselves along with their inventions, is Mr. Rae Winans, of Vernon, in New Jersey, whose patent is dated the 28th of May 1830, and is entitled, " Certain improvements in diminishing the friction of wheel carriages, to be used on rail or other roads." Mr. Winans proposition for effecting this desirable achievement, is a very ingenious modification of various other abortive plans (which, in the language of mechanics, and for the want of a more suitable term, is denomi nated) on the same principle. Mr. Winans suspends the weight of the carriage on the interior of a set of friction wheels, whose peripheries extend considerably beyond the axes on which they turn. One of the advantages pointed out by the patentee is, that in cases of slight turnings, or (inequalities in the railroad, the pivots resting on the peripheries of the friction wheels will pass a little backwards or forwards, and thus permit the wheels to accommodate themselves to the rails. Some comparative experiments on the friction of the axles of these carriages were instituted by the Manchester and Liverpool Railway Company, under the superintendence of Messrs. Hartley and Rastrick, of which Mr. Wood has given us an account, which we are induced to insert in this place, as it tends to throw considerable light on a subject upon which much study and ingenuity has been wasted.
The carriages tried were the several contrivances of Messrs. Winans, Brandreth, and Stephenson, and were of the following construction. In Mr. Winans' carriage the axles, projected through the naves of the wheel, were made to run upon the interior of the periphery, or inside of the rim of the friction wheels. The body of the carnage No. 1 of the experiments, consisted of a platform, with four cast-iron wheels, each 20 inches diameter, which ran upon the rails; the axles of these projected through the naves, the ends being 1 inches in diameter, and 2 inches long, and rolled upon the inside of the rim of four friction wheels, S inches in diameter, which friction wheels were sup ported by a journal, 1 inch in diameter, and 11 inch long. No. 2 did not differ from this in construction, except the travelling wheels, which were in this case 30 inches in diameter, and case hardened.