Welsh Journals

Search over 450 titles and 1.2 million pages

TMF. BR I $ To b, A«A..Ll ] No. 9. Monday, May 7,". Ilalf-penny. Illustrate* SrtwU. DESCRIPTION OF MR. GTJRNEY's NEW STEAM CARRIAGE, BY MR. HERAPATHOF CRANFORD. " The present carriage dif¬ fers from the earlier carriage, in.several improvements in the machinery, suggested by ex¬ periment; also in having no propellers; and in having only four wheels instead of six; the apparatus for guiding being applied immediately to the two fore-wheels, bearing a part of the weight, instead of two extra leading wheels bearing little or none. No person can conceive the absolute control this ap¬ paratus gives to the director of the carriage, unless he has the same opportunities of observ¬ ing it which I had in a ride with Mr. Gurney. Whilst the wheels obey the slightest mo¬ tion , of the hand, a trifling pressure of the foot keeps them inflexibly steady, however rough the ground. To the hind axle, which is bent into two cranks, at right angles to each other, is applied the pro¬ pelling power by means of pistons from two horizontal cylinders. By this contrivance, arid a peculiar mode of admit¬ ting the steam to the cylinders, Mr. Gurney has very ingeni¬ ously avoided that cumbersome appendage to steam-engines, the fly-wheel, and preserves uniformity of action by con¬ stantly having one cylinder on full pressure, whilst the other is on the reduced expansive. The dead points—that is, those in which a piston has no effect from being in the same right line with its crank,—are also cleared by the same means. For as the cranks are at right angles, when one piston is at a dead point, the other has a position of maximum effect, and is then urged by full steam power; but no sooner has the former passed the dead point, than an expansion valve opens on it with full steam, and closes on the latter. Firmly fixed to the extremities of the axle, and at right angles to it, are the two ' carriers'—(two strong irons extending each way to the fel¬ loes of wheels.) These irons may be bolted to the felloes of the wheels or not, or to the felloes of one wheel only. Thus the power applied to the axle is carried at once to the parts of the wheels of least stress— the circumferences. By this artifice the wheels are required to be of no greater strength and