!Pigs. 4 and 5 show two different applications of the invention from that snown .n .F7g. 2 ; for in these instances there is only one pulley, whilst the two fiont ar two back wheels of the carriage act the part of the other pulley. In Fig. 4, a is one of the front wheels of the carnage, which also acts as the larger pulley ; b is the smaller pulley, and is the only one around which the rope c d = es ; the wheels a, and the pulley b, being on the same axis g, which runs side to ride of the carriage, and turns in bearings affixed to the carriage. In this arrangement the point f, at which the wheels touch the rail, becomes the fulcrum on which the w' eel a turns ; and it will thus be evident that if the rope c d be drawn forward in the direction of the arrow, a similar effect will be produced as described in Fig. 2, and as shown in dotted lines in .F1g. 4. theless, if the wheels and pulleys a and b be of the same relative diameters u those in lig. 2, the carriage at lig. 4 would only be propelled at the velocity or seven to one, owing to the fulcrum, at which the wheels a turn, being remorred from the mean point f, Fig. 2, between the two diameters, and placed at the extreme end of a radiating line, drawn from the centre of the wheel a to the point at which it touches the railway. In Fig. 5 the rope is passed around the pulley a, which is the larger, whilst the carriage-wheels act the part of the smaller pulley b, the pulley a and the wheels b being on the same axis g. In order that the pulleys in this arrangement may stand at an angle for clearing the rope, the axle g is formed of three parts, connected by universal joints; and one of the wheels b thus travels a little forwarder than the other, and thus the rope will clear itself. And, it should be observed, that in both these arrange ments, the pulley around which the rope passes is to be made capable of being disconnected from revolving with the axle as described in Figs. 2 and 3. in the arrangement, Fig. 5, the fulcrum f, on which the wheels turn, is the point at which the wheel b touches the rail or road ; and the difference in the arrange manta, Figs. 4 and 5, is, that the power in IV. 4 is applied by the rope between the fulcrum f, and the centre g, of the wheels or pulley a b, where the weight to be drawn is attached ; whilst, in Fig. 5, the fulcrum is between the centre of the pulley and wheels a ; consequently, the arrangements differ in the order of leverage, and, in this instance, will be as six to one. In these two last arrange ments, the rope c d may be either an endless rope, as described in Figs. 1 and 2, or the rope may be single, and, taking a turn around the pulley a or b, is to be wound on a drum at each end of the distance, which is to be run by one length of a rope.
This invention has been recently tried on a piece of railway near the Regent's Park, and, we are informed, did not fulfil the anticipations of the ingenious patentee. The proposition, however, possesses merit, and may be very beneficially carried into effect for short distances.
In our, notice of Sir Charles Dance's carriage at page 173, we alluded to a i boiler that was Introduced into it in 1833. It is thus described by Mr. Gordon :— " In 1833 a patent was obtained by Sir Charles Dance and Mr. Field, for an arrangement of tubes, which was considered superior to Gurney's. The bent pipes of Gurney's boiler will be discovered upon reference to the figure, and the whole will be found to consist of two of Gurney's boilers, but without the sepa rators backed into each other. The coil-pipe J is here used, conveying the cold, or rather the cooler, water from the tank to E, from whence it rises to C, becoming heated in its passage upwards. Water pumped into D also ascends to B in the same manner ; and at B and C the steam from the two distinct boilers E C and D B, rises up to F and G, and is drawn off to the engines, whilst the cooler particles descend in the vertical pipes below C and B, to pass again over the fire with other water, going in the upward direction.
A tubular boiler for locomotive purposes, of considerable efficiency in the production of steam, was patented jointly by Mr. John Squire and Colonel Maceroni, on the 18th July, 1833. It consists of nine rows of upright cylin
drical tubes, each row containing nine tubes, so that there are eighty-one in all. In the middle of these the fire-place is situated ; and to obtain the requi site space for it and the fuel under combustion, a portion of the interior ranges of tubes are proportionably shortened, as well as three of the front tubes, to form a fire-door. All the vertical tubes are connected by means of small hori zontal tubes at the top and at the bottom; the upper being a steam communi cation, and the lower a water communication ; but as they are all open to each other, and the application of the heat cannot be precisely uniform in every part, a circulation of the fluid necessarily ensues. To avoid clinkers, and prevent the destruction of the fire-bars, the latter are formed of hollow tubes, filled with water, and communicating with the vertical tubes. The steam is conducted from the latter tubes, by means of small pipes entering the otherwise close tops of each, into a central recipient, from which the engine is supplied. The flame and heated matters being diffused round and throughout the whole series of tubes, of course produce a rapid generation of steam.
Having thus obtained the heart and vital fluid for locomotion, Messrs. Squire and Macaroni set about combining the sinews, bones, and joints, which com prise the entire machine ; of which the following cut will afford a tolerably cor rect ides.
This carriage, Mr. Gordon says, "is a fine specimen of indomitable perse verance," and that it is not uncommon to travel from 18 to 20 miles per hour by it. The engines are placed horizontally underneath the carriage body ; the boiler is at the back, and a winnowing blast is employed to excite the cainbus don of the fuel, the supply of which is regulated by an engine man, whlrhas a seat at the back for attending to it. The passengers are placed in the open carriage body, and their seats are formed upon the tops of the water tanks. There are two working cylinders 7 inches diameter, and 151 inches length of stroke. The steam-ways are 2* and 2f inches diameter. We regret that our space will not permit us to extend our notice of the operations of the highly gifted Colonel Maceroni ; but our readers who have not seen his Expositions and Illuaratiosu in steam locomotion (published by Effingham Wilson and George Hebert, 1835) may derive therefrom much useful information, as well as amusement.
In the course of this article, we have described a variety of ingenious con trivances for enabling locomotive carriages to pass over obstacles lying in the road, without injury resulting. The invention we have neat to notice is of that description, and is the subject of a patent granted to Mr. George Millichap, of Birmingham, and sealed on the 31st of March, 1834. The carnage is mounted upon three pair of wheels, whereof the foremost and the middle pair are situated in their usual places in four-wheeled carriages; but the additional third pair, herein alluded to, are quite at the back, and much nearer together than the others. The fore wheels are made to lock much in the usual manner, and above them is a framework, carrying toothed gear, by which the carriage is steered, when acted upon by the guide, through the medium of suitable levers. The axis which carries the middle of wheels, passes through projecting arms at the fore extremity of the principal platform or floor of the carriage, which platform rests upon the axletree of the hind wheels, about two-fifths of its length bum its bind extremity. Should an obstacle therefore present itself against the middle pair of wheels, (and a very formidable one is shown on the drawings of the specification,) it does not become necessary to lift up the whole weight of the carriage and load, but only rather more than the weight of the wheels, as the axletree of these acts like a hinge-joint, and the platform of the carriage yields to the resistance, by collapsing, or turning upon its joints. For the sake of illustration, a train of gear, of different speeds, are shown as worked by hand ; but the patentee observes, that steam power may be obviously communicated to it, in lieu of manual labour.