iS 



THE CIVIL ENGINEER AND AUCHITECT'S JOURNAL. 



[FEBBnARY, 



astern." An aftei--bearin;^ for the sliaft may be fnrmeil by the 

 nietal-i-dil e, set up with a screw to tlie stern ; wliich rod wouhl 

 also form an additional stop for the propeller on the shaft in back- 

 ing astern. Or a rod nii^ht be attaclied to the upper and after- 

 part of the lioistinii-franie, and set u]) with a screw to the vessel's 

 stern ; and a small rod may be a|iplied at the aft-side of tlie hoist- 

 in^-frauie, for iriscrtintt a forelock in the end of the sliaft, to secure 

 the pr()i)eller iji I)ackiufr astern, which forelock would revolve with 

 the shaft on the pin at ,r. The surface of tlie rudder may be as 

 lar^e as that of the innnersed part of the common rudder, althoui;h 

 !is the pressure of the water on such a rudder would be once and a 

 half as great as on the common rudder, a nnich smaller surface 

 would be sufficient for steerinjj, and the lower part might be re- 

 duced. 



A large and very strongly formed rudder-band is fitted at the 

 ui)i)er p.^rt of the rudder, with a large hole through it, of a square, 

 hexagimal, or other form, into which the rudder-head r is fitted 

 f(U- turning the rudder ; the lower rudder-bands might also he 

 formed similarly, and the braces fitted with an internal ring, that 

 tiie rudder-head being extended downward as a substitute for the 

 rudder-pins, may revolve in the braces, whilst it is fixed in the 

 rudder-bands for turning the rudder. The rudder-head above the 

 upper rudder-baud is cylindrical, and ))asses through a metal cylin- 

 der with a stuffing-box-'. It then surrounds the propeller-shaft so 

 that the rudder may turn sufficiently in steering ; and it extends 

 to any convenient height to receive the tiller. Slu)uld the rudder 

 be carried away a temporary rudder could be applied, by taking up 

 the propeller, using sails only, and liaving the temporary rudder 

 prepared with braces to slide down the sternpost grooves ; by which 

 it would be held securely to the ship, its lower end being secured 

 with guys. 



The advantages to be obtained from this improvement are, the 

 maximum effect of the screw-i)ropeller in pnipelling ; the avoidance 

 of risk of serious damage from a vessel's grounding, and the pre- 

 servation of the strength, aiul the form, and the displacement of 

 the after-])art of a vessel. 



The claim is for the right of applying a screw-propeller and a 

 rudder conjointly to a ship or vessel in the positions above-men- 

 tioned, and' as shown in tlie engraving. The improvement in steer- 

 ing vessels consists also in applying a similar rudder to a ship or 

 vessel not jiropelled by a screw. 



Such a rudder could be either shipped or unshipped afloat, by 

 attaching a water-tight hose or cylinder to the rudder-head cylin- 

 der, so that the rudder-head r, with the rudder-pin or pins attached 

 to it, may be drawn up in unshipping the rudder, or replaced in 

 shipping it. The keel may extend under the rudder, as shown in 

 the engraving, to protect it in grounding. 



The advantages of such a rudder are, much less first cost, inde- 

 finite durability, through being abvays under water, being below 

 the impulsi-s of waves, so that tlie steering would be uniformly 

 steady, and without hazard to the helmsman, both when a ship is 



laden, and when she is light ; and it is quite below the reach of 

 shot. 



Another improvement in propelling vessels consists in making 

 that part of the immersed volume, which is abaft the vertical and 

 transverse plane in wliicli the centre of gravity of the vessel is, of 

 such a form, tliat the longitudinal staliility of the after-eud of the 

 vessel may be jiractically equal to that of the fore-end : — in order 

 that the pitching motion, so far as it may be caused by the form of 

 the immersed volume, may be prevented ; and that there may be 

 the least possilile resistance of the water to the propelling power. 

 This is of especial importance in screw-propelled vessels, because 

 pitcliing raises the screw above the waters surface. 



The equal staliility of the fore and the after-ends of a ship, is 

 obtained by making the area of the load-water section abaft the 

 above-mentioned vertical and transverse plane, eipial to the area 

 of the remaining part of the same water section, on the fore-side 

 of the same plane ; and the moments of those areas, from the same 

 vertical and transverse plane also equal; and by forming the lower 

 horizontal sections m- water-lines in a similar manner ; or so that 

 the cubic contents of the immersed volumes, on eacli side of the 

 same vertical and transverse plane, and the nujments of the same 

 immersed volumes from the same plane, sliall likewise be equal, 

 the one respectively to the other. A vessel of remarkably beauti- 

 ful form may thus be produced. As the propelling power of the 

 wind on the sails always depresses the fore-end of a ship, when it 

 impels her onward, just as it depresses the lee-side, when the wind 

 acts obliquely, it appears contrary to the dictates of reason and of 

 science, that ships should have, as they commonly have, less sta^ 

 bility at the fore-end than at the after-end. By nuiking the stability 

 equal at both ends of a ship the pitching would be reduced to the 

 least possible degree, the propelling power would produce greater 

 speed, the decks or gnu-platforms would be kept more nearly in 

 their horizontal positions, and the dangers and discomfort and ex- 

 pense of " wear and tear," in rough weather, would be materially 

 diminished. 



The claim is for making ships or vessels of the form above de- 

 scribed, so that the longitudinal stability of the foi'e-end may be 

 practically equal to that of the after-end. 



LOCOMOTIVE ENGINES. 



Thomas Russell CKAJiPTo>f, of Adam-street, Adelphi, engi- 

 neer, for " Improvements in locomotive enyines." — Granted June 19 ; 

 Enrolled Dec. 19, 181.7. 



The improvements relate to the construction of the locomotive 

 engine. 



'riie first improvement consists in introducing two pairs of 

 driving-wlieels, one pair to be placed behind the fire-box, and the 

 other pair forward, in such manner that the weight of the boiler 

 and machinery may be borne equally by each pair of driving- 

 wheels. By this arrangement, the adhesion of the wheels upon 

 the rails will be more uniform. The two pairs of driving-wheels 

 are to be connected on the side by rods in the usual manner, or 

 connected separately to the driving cylinders, or in any other con- 

 venient manner. The mode preferred by the patentee is shown in 

 the seventh improvement. If it be desirable to construct the 

 engine with six or more wheels, the patentee proposes to ])lace 

 them between the two pairs of driving-wheels, but recommends 

 that they should bear but little of the weight, by the employment 

 of light elastic springs. 



The second improvement is in the construction of the fire- 

 boxes, for tlie reception of the axles of the driving-wheels, the 

 driving-wheels of the locomotive engine being placed more forward 

 than the back of the fire-box. If large wheels are to be used, a 

 recess is to be formed transversely in the upper part of the fire- 

 box for the axle ; and for smaller wheels, a recess is to be formed 

 in the lower part of the fire-box : this latter arrangement divides 

 the fire-bars into two parts. By either arrangement, the heating 

 surface of the interior fire-box is increased, and the evaporative 

 power of the boiler augmented. 



The third and fourth improvements consist in such arrangement 

 of the various parts of the locomotive, that the axle of tlie fore or 

 leading wheels may have outside bearings, and the axle of the 

 drawing or after-wheels behind the fire-bo.x, inside bearings. 



The fifth improvement consists in placing the eccentrics for 

 working the valves on the outside of tiie driving-wheels, by elon- 

 gating the axle some distance through the boss of the driving- 

 wheels ; the crank-pin, instead of being fixed to the boss of the 

 driving-wheel, is fixed to a suparate crank fastened to the end of 

 the elongated part of the axle, leaving sufficient space between 



