THE MECHANICS' MAGAZINE. 'LONDON: FRIDAY, JULY 24, 1868. promptitude and precision the changes of tion of the ships may be neglected, and the UNIFORMITY OF SPEED IN SHIPS the orders issued by Count Bouet-Willaumez OF WAR. T would be well if the admiral in command in April, 1864, and afterwards practised suc- Iwo the English ironclad Channel fleet Channel. It was found that these orders led to precison of action at a time when the regu- Captain Bourgois refers to the difficulty were to institute experiments and evolutions The following is an illustration of the experiments respecting the advance per revolution, the co-efficients of advance of ships, and the efficiency of the engines : Let V N A = = velocity of the admiral's ship in Then we have V = NA 60 If n and a be the same quantities for any ship whose speed is the same (V), we have or It is often desirable, Captain Bourgois states, to know the co-efficients of advance of the ships of a squadron at the commencement of a cruise, as, for example, when it is supposed they will vary with changes of immersion, and the state of the ships' bottoms. The experiment is then restricted to one or two hours at most, and account is taken of the changes in the relative positions of the ships, which cannot be neglected on account of the short distance run. The following was the mode adopted :-Directly the signal for the commencement of the experiment was made, each ship's bearing and distance from the flag-ship were determined by observations. These observations were taken on board each ship, and on board the flag-ship they were made for each ship of the squadron. The means of the observations served to trace a of advance which equals the ratio of advance diagram showing with sufficient exactitude By means of trials over a measured dis- per revolution of the admiral's ship to that of the relative positions of the ships at the comtance, under the same conditions of sea, wind, the ship under notice. Hence, the relations mencement of the experiment. Similar obimmersion, condition of ship's bottom, and between these advances being known, the co-servations made at the conclusion of the speed, the relation between the number of re- efficient can be determined either by one ex-experiment furnished the elements of a second volutions per minute, and the velocity of the periment or by two distinct experiments on diagram, which was constructed on the first, ship's way, is determined. The admiral is the vessels compared, provided only that the thus enabled to translate and signal in num- same conditions of time, speed, velocity, imber of revolutions of his engines the speed mersion, and condition of ship's bottom are that he fixes for the squadron, and each secured. The only method which was found captain, by using the co-efficient of advance of to secure this identity of conditions for all his vessel, can determine the mean speed re- the ships of the squadron was to submit them quired for her engines. The speed of the at one time to the same experiment that is engines cannot be preserved with mathe- to say, to drive all at the same speed for a matical exactness, but the variations thereof certain time, and compare the total distance can be indicated by the height to which the traversed by each with the number of revolutwo black signal balls are hoisted in the rig-tions of the screw during the same time. If ging; and on the attention paid to this signal the co-efficients of advance are all that is reby the officer of the watch, the preservation quired, it is sufficient that the distance run of position principally depends. It is also is the same for each vessel, and that the the duty of the officer of the watch to deter- number of revolutions performed while tramine his position relatively to the leading versing this distance is observed for each vessel by the bearings and angular elevations vessel. The co-efficient for a vessel is, then, of her masts, and to regulate the speed of his determined by dividing the number of revoluengines by the changes he observes. It is tions of its engines by those of the admiral's essential that the engineers thoroughly under- ship. If, for example, in a squadron sailing stand the degree of influence exerted by va- in regular order, all the vessels signal each riations of the pressure in the boilers, of day at a fixed time, the number of revoluvacuum in the condensers, of the opening of tions performed since the last signal, on valves, and expansion, &c., on the speed of account of its long duration and the distance their engines, in order to perform with traversed, the slight changes of relative posi supposing the position of the flag-ship to have remained unaltered. This double diagram gave the exact change of position of each ship, with respect to the flag-ship, which had taken place during the experiment. In the most general case, when the time of the trial had not been too short, and the regularity of the order not much disturbed, the projection of this change of position on the common course gave a sufficiently close approximation to the difference between the distances run by the flag-ship, and that gone over by the ship under notice. Hence also the difference of their speeds during the trial was known. Beyond this each ship threw the log, and signalled the results obtained at close and regular intervals. The mean speed thus found, corrected by the above-mentioned difference, determined the speed of the flagship, free from the greater part of the errors of the log, and of individual mistake. The ratio of distance run to the number of revolutions during the time gives the value of the advance per revolution, and hence, as before shown, the co-efficient of advance may be de duced for the conditions of time, speed, immersion and state of bottom under which the experiment has been made. There is much other detail in the treatise before us, in reference to obtaining the uniform speed of ships by the means before described, but we cannot here go into the matter more fully. Vice-Admiral BouetWillaumez also instituted elaborate experiments with regard to the rolling of ships, turning, the management of their engines, and navigation in squadron, some of which we intend noticing in a future number of this journal. WIMBLEDON, 1868. THE meeting of the National Rifle Asso Tciation for the present year will, in some respects, be one of its most memorable gatherings. The insufferable heat under which the shooting has been carried on has been terribly trying to all, and, unfortunately, fatal to some. The power of the sun has also several times endangered the safety of the camp, fire having broken out in many places from causes totally inadequate to effect such results under ordinary circumstances. Notwithstanding these and other drawbacks the shooting has been decidedly good, and the various contests severe. The highest scorer for the Queen's Prize, Corporal Peake, of the 6th Lancashire Volunteer Corps, unfortunately used a wad other than that prescribed by the regulations, and so, after being chaired and feasted in triumph on Tuesday evening, was shorn of his honours on Wednesday morning by the council. The honour was then transferred to the next best scorer, Lieutenant Carslake of the 5th Somersetwhether rightly or wrongly we do not presume to say. All we can say is that those who informed against Mr. Peake and his unlucky wad at the last ought to have done so at the first, or even to have stopped the promising competitor in the early part of his career. But it is not so much with the routine business of the Association that we have to deal, as with the novelties in the way of new arms that were entered for trial. Of course, the direction of improvement at the present time lies chiefly in breech-loaders, and here we found several new friends, and many old ones a little better in some respects than when we last saw them. Including the Snider Enfield, the breech-loaders were represented by thirteen of their species. The Soper rifle was there and did well, and some there were who predicted for it every success. Then we have the Carter and Edwards, the Kerr, the Henry, an improved Berdan, the WalkerMoney, the Wilson, the Boucher, the Westley Richards, the "B. B.," the Cooper, the Newark central-fire, the Bissell, and the Metford rifles. Looking for a military rifle amongst these we should at once point to the Henry, the Kerr, and the Berdan as examples which had shown their fitness for this use. THE MILLWALL SHIELD. CROSS SECTION. 7. 2. One point struck us very forcibly, and that was the total absence of magazine or repeating rifles. And we were not alone in our surprise, for there were, to our knowledge, several inquiries about them. We had hoped to have seen the Spencer repeating rifle represented, for undoubtedly, now that the magazine can be shut off and the piece used as a simple breech-loader, this arm is the most effective of its class. We think it a pity the weapon should be lost sight of, and suggest to those who may take an interest in it that they should see to its proper representation next year. We are satisfied that it would prove admirable as an arm of war for cavalry which can go through infantry drill; the most remarkable results would attend its use, as, indeed, they did over and over again during the American war. Let those who represent this arm keep it before the public service, for we assert that within certain limits and under certain conditions it would prove a most valuable weapon for a portion of our forces. THE MILLWALL SHIELD. The Henry rifle was fired with wonderful THE only shield of importance remaining placed vertically, except above and below the porthole, where they run horizontally. To support these stringers are two box-girders, 12in. deep, placed horizontally, and on each side of porthole two similar girders occur at right angles. The whole are riveted to a 14-inch plate, and 34-inch bolts-on Mr. Parsons' system-pass through from front to rear, fastening the whole structure together. The stringers, the spaces between, and the girders, are filled in with wood, with the exception of the hollow part of the stringers on the right. The shield was originally designed in 1865, with the exception of the girders in the rear, which have been added by direction of the War Office during the present year. The advantage gained by the form of backing DIACRAM OF FACE success. This structure is known both as the The Millwall shield was ordered by the War Office authorities with the view to obtaining three experiments at the expense of one shield. This is rather unfortunate. because it will not give correct data upon which to form an opinion of the merits of the hollow stringer principle, that being based upon the stringer being of the same depth as the thickness of the overlaying armourplate, the diameter of bolts and the thickness of skin-plates being in due proportion also. On this principle the 9-inch plate should have had a stringer 9in. deep, two skin-plates 14in. each, and 33-inch bolts. The 7-inch stringer should have had a 7-inch armour-plate, two skin-plates lin. each, and 34-inch bolts. The deviations were made on the score of economy by the War Office authorities, and of course we must accept them, although it should be fairly understood by the public how the matter stands. Much more practically valuable results would have been obtained had the shield been entirely covered with one thickness of plating-say 74in. or 8in. The weight of the shield is about 37 tons, but then it should be remembered that this includes the three laminated 1-inch plates, which weigh 1 ton, and are of little value to the target as regards its resistive strength. If, therefore, we take the Millwall shield as a 353-ton structure, we shall be correct for all practical purposes. As regards cost, it is about the same as that of the Gibraltar shield, which is the heavier structure of the two. It is, therefore, as against this shield that we must consider Mr. Hughes's structure, and looking at it in this light the Ordnance Select Committee decided to test it under precisely the same conditions of range and fire as was done in the case of the Gibraltar shield. The trial was carried out yesterday week at Shoeburyness, the following guns being brought to bear upon it at 70yds. range, viz., the 15-inch bore, 450-pounder American cast-iron smooth-bore gun of 19 tons 4 cwt. 2 qr. 261b., mounted on a wood garrison carriage on a wooden garrison platform; the 10-inch bore 400-pounder muzzle-loader, rifled in seven grooves, of 18 tons 3 cwt. 2 qr. 4lb.; and the 9-inch bore 250-pounder wrought-iron muzzle-loading gun, of 12 tons 4 cwt. 1 qr. Slb., rifled in six grooves, both being mounted in a similar manner. The powder used was rifled large grain, similar to that used against the Gibraltar shield. The official programme of the firing was as follows:-Round 1.-A 9-inch Palliser shot, head 1 D, charge 371b.; directed under and to proper right side of port. Round 2.-A 9-inch Palliser shot, head 1 D, charge 371b.; directed at proper left of port. Round 3.-A 9-inch Palliser shot, head 1 D, charge 371b.; directed at proper right top corner. Round 4.-A 9-inch Palliser shot, head 1 D, charge 37lb.; directed under and to proper left of port. Round 5.A 15-inch Rodman, solid shot, charge 50lb. (English powder); directed at proper left bottom corner. Round 6.-A 9-inch Palliser shell, head 1.5 D, charge 431b.; directed at proper right side of port. Round 7.-A 9-inch Palliser shell, head 15 D, charge 431b.; directed at proper left top corner. Round 8. --A 9-inch Palliser shell, head 15 D, charge 371b.; directed at proper left side of port. Round 9.-A 9-inch Palliser shot, head 15 D, charge 43lb.; directed to strike on No. 3. Round 10.-A 10-inch Palliser shell, head 1.5 D, charge 54lb.; directed to strike below port. At the conclusion of this practice, the committee will decide on whatever further experiments may be necessary. The 371b. charges give the equivalent to battering charges of 431b. at 400yds. The 54lb. charge is the equivalent to the full battering charge of 60lb. at 400yds. In the first round the shot struck the 9-inch plate (A) between three bolts, the penetration being 10in.; the shot broke off level with the face of the plate, leaving the head in the hole. The shield was slightly moved backwards; no damage whatever was done to the rear. The second shot struck the 6-inch plate (B) in a line between two bolts, and stuck in the plate whole. The indent made was 144in., the plate buckling in., and the shearing of four 1-inch rivets. Besides separating in. from the three plates of the the breaking of the edges of three cast-iron C section. Beyond the crushing of the india- washers, no further hurt was done to the rubber packing of three of the large bolts, shield. and the jambing off of a piece of one of This was the close of the official programme, the cast-iron washers, the rear was uninjured. so far as had been arranged. But at this The third shot struck the C section, hitting point the committee determined to submit the head of a bolt, which was knocked into the structure to a further test, and five a semicircular mass, and 80yds. to the front extra rounds were fired. The first of these of the target. The shot hole was 9in. in dia- was a large capacity Palliser shell, which meter, no fissures appearing. The projectile struck the lower edge of the 9-inch plate, rebounded 8ft. to the front, minus a small cutting out a circular notch without making portion of the rear end. A slight crack ap- any fissures. The shell burst under the peared in one corner of the outer 1-inch target, making a hole in the earth 5ft. by plate, and a small piece was broken out, 2ft. 6in. by 14in. deep, smashing the wooden whilst at another point all three plates were screen, the fragments of which were thrown split across. No damage was done at the 50ft. to the rear; no harm resulted to the rear, unless the starting of the 3-inch bolt- shield. In the second of these extra rounds, the head of which was thrown to the front, the shell struck upon the junction line of the and the jarring off the heads of three of the 9-inch and 6-inch plates in No. 6 shot-hole, countersunk rivets-be considered as such. the result being a hole 15in. by 10in., the The fourth shot struck the lower 9-inch plate head of the shell remaining in; a triangular between three bolts, penetrating 9 in., and piece of the 9-inch plate was split out, and rebounding 10ft. to the front. The plate the junction line of the plates was opened a buckled inwards around the shot hole, so that good inch. The rear was unhurt, except the bolt heads projected slightly. At the that a bolt was started about 14in. out and rear nothing was disturbed, except that a two cast-iron washers were chipped. piece of a cast-iron washer was broken away. next shell broke up in the gun, the langRound No. 5 was with the Rodman gun, the ridge marking the face of the target. Round shot from which struck the 9-inch plate (A) No. 4 was a shell which struck the 9-inch between three bolts, and rebounded 6ft. to plate just below the porthole, breaking out the front in a disfigured condition. There the front mould 4in., one piece, weighing was an indent of 3in. and a slight buckle, about 150lb., being thrown 2ft. to the front. half of one of the bolt heads being pressed The total indent was 22in. The face of the into the indent. At the rear the fittings for target was started from its fittings some 3in., keeping the target in position at the proper and the separation of the 9-inch plate along left side were much disturbed. A large block the line of weld was extended about 6ft. At of chilled iron, some 2ft. square, was lifted the rear seven rivets were driven off from the up, and the wood wedges jamming it tight angle iron attached to base plate, the angle were driven out. The bolt securing a strong iron being cracked through in two places at iron strap over this woodwork was broken off the rivet holes. The final shot-making, in and the strap knocked up. No damage what-all, fifteen that had been fired-was from the ever was done to the back of the target, except that the edge of one cast-iron washer was broken. The costly as they have been, will doubtless bear fruit one day, when careful investigation of the whole results shall have been made by competent and unbiassed judges. Rodman gun, and it struck the top of the porthole, making a hole 1ft. 3in. across, by 1lin. high, which extended inwards, gradually The next round was a shell, which struck inclining downwards for 14in., where the close to the horizontal junction of the 9-inch fragments of the shot glanced upon the inner and 6-inch plates midway between four bolts. edge of the portsill, battering it for a length The total indent was 12in., there were no of 20in; the angle iron of the lintel driven fissures; the upper arch of iron forming the down at proper right edge 6in., numerous edge of the plate was only lin. in thickness, fragments of the shot passing through the but yet was not broken through. The lower porthole. No damage was done at the back edge of the 6-inch plate over the shot hole of the target, but the whole structure would rippled up but was not broken. The head appear to have been lifted bodily up by this of the shell rebounded 1ft. to the front. shot, as the rear connecting plate of the struts The plates were, to a slight extent, sepa- was bent up about 6in. This concluded the rated from the backing. In the rear, the series of experiments, which cannot be proonly perceptible damage was, that one of the nounced otherwise than highly satisfactory 3-inch bolts which passed through the in every respect. Whether we consider the hollow stringers to the back of the face-plate splendid quality of the iron, or the successful was driven in lin. The shell from the resistance offered by the backing, we can seventh round struck near the top of the 6-only come to the conclusion that great credit inch plate midway between three bolts. The is due to Mr. Hughes. These experiments, head remained in the plate, the total penetration being 104in.. Two small bolt heads were jarred off from the laminated 1-inch plate, and a fine crack, 10in. long, was perceptible in the horizontal stringer at the top of the shield, no damage being effected in the rear. At the eighth round, the Palliser shell broke up in the gun, the head, and some fragments of the shell, marking the face of the target. The ninth shot struck upon the horizontal junction of the 9-inch and 6-inch plates, the hole disclosing one of hazardous, more full of trouble, uncertainty, the hollow stringers, which was much dis- and vexation, than the reclamation of land torted but not broken. The total penetra- from the sea. In many instances it has been tion was 12in.; a slight fissure was started, successfully accomplished, and in many it but no damage, beyond the starting of a has failed irredeemably. Not that the work bolt, was done in the rear. The final round is of a very diflicult character, or the materials of the series was a 10-inch shell, which of a very expensive description, but the water struck upon the covered portion of the 6-is the great enemy to contend against-the inch plate (C), entering the shot hole No. 3. difficulty to be overcome. In general, the reThe total penetration was 243in., the shell remaining embedded whole in the plate. It struck the shank of the bolt which was damaged in the third round, and drove it out through a 1-inch deal screen 30ft. to the rear. The narrow lining plate was driven out over a length of 4ft., and about 1ft. of the end of one of the hollow stringers was burst out by EMBANKMENT OF TIDAL LANDS. No. I. all the works that fall to the lot of the O engineer to execute, there are none more clamation is effected by enclosing the area from the sea by a long embankment or dam, with cross dams at intervals. Manifestly, it will depend upon the number of cross dams employed whether the land, if of large area, can be reclaimed in one or more years. The establishment of cross dams at intervals throughout the length of any enclosed portion chines were started at five minutes' intervals, and in of land is not in ordinary cases a work of eagerly coveted, as the soil is then virgin, gear, consisting of a Clayton and Shuttleworth absolute necessity so much as one of precau- and the names of intending tenants are sent 10-horse traction engine, a set of Smith's roundtion, in order that in the event of a giving into the proprietors months before the land about gear, two cultivators, a drum, rope porters, way of the main longitudinal dam, techically is ready for the willing husbandmen. Com- &c., making a train of 34 yds. long; fourth, Aveling termed a "blow," the inundation might be only monly, the demands for land exceed two or and Porter's engine, with Fowler's roundabout of a partial instead of a general character. three times the area available, so that the system and drum, a long string of porters, making It frequently occurs, from the peculiar shape proprietors are enabled to make some choice drawn by eight horses; and sixth, Hayes' set, also up a length of 54yds. in all; fifth, Howard's gear, and features of the land to be reclaimed, or selection of their future tenants. As all worked by a portable, and drawn by eight horses. that the construction of the cross dams, of them have some other land to farm in the The course was 500yds. long, and in front of the instead of being a secondary or subsidiary interior, not more than from twenty or thirty engines was a fence, which, though it had a gap operation, becomes one almost equal in mag- acres are granted to each. Evidently, the cleared in it, presented anything but a smooth pasnitude, cost, and importance to that of the proprietors set their faces against a few ob- sage into the next field, out of which a sharp right main dam or embankment proper. Under taining a monopoly at the expense of the many. angle turning through a 7ft. gateway led on to these circumstances it is preferable, bearing The usual conditions of occupation are that the high road. Close to this gate the road makes in mind that the construction of a long cross the tenant bear all the expenses of cultivation, another sharp bend, whilst a third leads through dam is a somewhat hazardous operation, and sowing, and reaping, and deliver into the another narrow gate into the trial field. The mathat it is not always certain to be exempt barns of his master half of the crop, in a the course of working the great convenience of the from the same casualties attending its more proper state to be sold in the market. Owing back-and-forward system, adopted in Fowler's important neighbour, to give two or more to the excessive fertility of the land reclaimed tackle, and also in some of Howard's, but not in that years to the proposed reclamation embank- in the Bay of Bourgneuf, the company have which he exhibited, was clearly seen. It only ment, and omit the consideration of cross stipulated from their tenants that in addition occupied twenty minutes with the double drum dams altogether. This was the plan adopted to the half profits they shall pay them an engine, and thirty with the clip drum, to get this in the reclamation of an extensive area of annual rent of 1s. 6d. per acre. There is no direct tackle into action from the moment it tidal land in France, in the bay of Bourgneuf, question but that on the whole the system entered the field. The superiority was still more which was recently brought to a successful of a clear annual rent, without the condition marked when work began, for the fixed points in termination. The area recovered was nearly of half profits, would be the most acceptable this plan of working are only two, the engine and 1,000 acres, and the works were commenced and the best in practice for both parties. the moving anchor, or the two engines, in the case more than two years ago. Moreover, the Another modification in the usual conditions requires at least three other fixed points besides where two are used, whilst the roundabout system subsoil was of a very compressible nature, introduced by the company is that it requires the engine or drum, and two of these must be and from this circumstance, together with the half crop to be delivered not in grain but hand-shifted anchors adjusted for every successive the great length of the bank, which was over in sheaves, and although the farmers are saved furrow of the implement. The hardness of the two miles, it was impossible to have finished the trouble of thrashing and winnowing the ground greatly retarded some of the operations. the reclamation in one year. The embank-crop yet they lose the straw as a recompense, The general results of these time tests, however, ment is represented in longitudinal section in which serves to pay the company for those will be found summarized in the accompanying fig. 1, where A B is the line of its summit, C D operations which are conducted by machine tabulated statement:power. Generally speaking, the land reclaimed is cultivated for a great number of years, and sometimes indefinitely, without the aid of manure, by the simple rotation of wheat and beans, which constitutes the invariable system of the country, but notwithstanding the antiquity of the custom it is susceptible of much improvement. With a FIG.I DEPOSI CLAY B D the level of high spring tides, and E F shows the level of the deposit made by the sea. Fig. 2 is a plan, and the enterprise was commenced by the construction of that view to prevent the impoverishment of the portion of the embankment D E which lay THE ROYAL AGRICULTURAL SHOW AT LEICESTER. sides all the winter, it was necessary to HE preliminary observations on the Leicester show in our last issue, and the notices which protect its inside slope by a stone facing, in THE a manner similar to that adopted for the have preceded them, fail to give an adequate idea of the waves. anchor, waggon, and rope porters, forming a train Results of Time Tests for Steam Ploughs, &c. Observations. Capital performance. Anchors gave much trouble by slipping. 8 f18 stone. 30 150 14 33 71 21 1 20 1 1r. 36 6 6 40 248 1 40 Fowler, with 8-horse traction engine and clip drum, and five-tine diagonal culti- min. h. min h. min a. p. .................... mainly in working The dynamometer trials consisted experiments on the strain required for Howard's single breast subsoil, working 18in. deep, and his four-furrow ordinary implement, and Fowler's deep two-furrow Kent breast plough, his light four-furrow Kent breast, and his five-furrow digging breast implement. Howard's four-tine cultivators and his four-furrow digging breast were also tested with the dynamometer, and also tine digging breast, and five-tined cultivator. This Tasker's three-tine cultivator, and Fowler's fourterminated the direct tests of tractive force required, which were conducted with the admirable three-pulley dynamometer constructed for the Royal Agricultural Society by Messrs. Easton, Amos, and Anderson, which was used at the Newcastle show. It consists of a long beam supported on a truck, Messrs. Richmond and Chandler's excellent chaff-cutter will be fully described and illustrated in our next. Besides this machine, Messrs. Richmond and Chandler exhibited about a dozen of their old chaff-cutters, for which they are justly celebrated, and which, we believe, will stand their ground for years yet. They also showed a variety of corn crushers, horse gears, steaming apparatus, turnip cutters, root washers, &c. and carrying on its upper face three horizontal hibited a fine 10-horse ploughing engine, as one adapted for raising water from wells of any depth, pulleys about 15in. diameter, grooved for the trac- of a pair, with single drums for working on and forcing it any height by means of single tion rope; the two pulleys at the extremities of Fowler's direct two-engine system. This machine, double, or treble barrel pumps. The larger sizes this beam are fixtures; that in the centre is besides being in the maker's best style, has the may be used in place of steam engines for watercarried on a pair of long steel springs, which press gear for driving the drum much simplified, the works in small towns and villages, as after the first it with a known force across the line connecting vertical shaft being worked directly by mitre outlay the water is raised free of further cost. the two end pulleys. This instrument is placed in gear off the crank shaft instead of being driven They are also adapted for thrashing, grinding, the line of the traction rope which is passed across through a counter shaft, as in Fowler's present chaff cutting, pulping, &c., as well as pumping the faces of the three pulleys, the centre one on engines. Respecting the latter, we may observe water for the supply of stock, and purposes of the spring deflecting it from the right line that it that the Leeds firm exhibited the two finest irrigation. It will be seen that from the peculiar naturally takes from the strain under which it traction ploughing engines ever constructed. construction of these wind engines considerably runs; the amount of this strain is measured by They are nominal 20-horse engines, weigh about more power is gained than with engines made on the amount of the deflection imparted by the 15 tons each, and have two speeds for driving the the old system. The whole force of the wind is known force of the springs on the centre pulley, winding drum. and is registered by a pencil (in the usual way for such instruments) marking a waving line on a strip of paper, to which clockwork gives a uniform movement. The back strain of the slack rope is at the same time measured by the ordinary spring balance dynamometer, an average being taken of its indications, and that average deducted from the gross force shown to be indicated by the long dynamometer on the hauling rope. We shall publish the results of these experiments in due course. On the whole, these are unquestionably the most important and conclusively favourable trials of steam ploughs that have ever taken place. The harrow and roller experiments also showed how completely amenable to the power of steam these implements have become. We will now turn to the implements which form the subject of our illustrations, and which of course were exhibited in the implement yard. Mr. Marsden exhibited an improved Blake's stone crusher, which we illustrate at page 68. It is an arrangement for crushing small stone or gravel (which has been previously broken) into dust or sand. The eccentric shaft is Among the steam engines may be noticed a placed lower in proportion to the rest of the novelty in the way of price, viz., a 2-horse hori machine than in the case of the large breaker; one zontal engine, of good London make, by Messrs. toggle or knuckle joint plate only is used, and this Hayward, Tyler and Co., for the sum of £18. works in line with the lower extremity of the Some credit must be due to them for accomplishmoving face, thus the motion is purely a grinding this object, which, it may be inferred, has rewithout vertical movement at that point, which quired a great amount of care and thought in dealso has its surface corrugated with two or three sign and workmanship. A similar engine, on a long ridges, and thus tends to pulverize any sub-plain vertical boiler, is likewise exhibited by these stance passing through it. The stones introduced makers. They also exhibit a 6in. rotary fire enare previously broken, and should not exceed a gine. This is a novel arrangement of the already walnut or egg size, in which case they are gradually well-known California pump, the handiest of all reduced as they descend between the faces, and can be discharged in a fine sand if required. The machine is merely a smaller size and a slight modification of that which has proved so useful, but as such it has its special sphere of work, for it will grind ores and provide building sand in many a locality where it is not found. Messrs. S. Owens and Co., the hydraulic and general engineers, of Whitefriars, exhibited two double-acting horizontal steam donkey feed pumps, of novel design, for feeding boilers, supplying tanks, &c., which were in action. We also observed one of Mr. J. Bernays' patent centrifugal pumps delivering 700 gallons of water per minute. This firm also exhibited a small centrifugal pump mounted on a barrow, which has been specially designed for the use of the natives in India, to enable them to irrigate small plantations and farms. A variety of useful hydraulic appliances of their well-known speciality were also exhibited. utilized at the outside circumference of the circle described. The shutters of which it is composed are self-acting, and should the wind come with great force they feather and allow it to pass through without damage to the structure. Messrs. Warner also exhibited a Noria, or chain pump, double-acting pumps for ordinary purposes, be-in which were several constructive novelties. The cause of the ease and rapidity with which the buckets attached to the endless chain which runs valves can be got at. The guide for the piston rod, over the drum are made to deliver upon both which consists of a flat bar rigidly joined to the sides so that no water is lost, and consequently same and sliding in suitably notched lugs cast on the whole motive power used in raising it is made the under side of the pump barrel, has now tho- available. The Noria is suitable for raising water roughly stood its trial, and is found to wear very from a well or tank, when it has only to be deMessrs. Aveling and Porter's combined trac- well, while affording as good a guide as could be livered at the surface, and is, therefore, particution engine and portable crane is illustrated, wished. The pump is intended to be worked larly adapted for irrigating lands upon a low level. in side elevation at page 70 and in end eleva- either by hand or by steam power, and is mounted From its simple, yet strong construction, it retion on the opposite page. It presents several on a strong and neat wooden frame with iron axles commends itself for the colonies where repairs features of novelty, the principal of which and four wooden or iron wheels, the forewheels are difficult, and where skilled labour for the erecis the combination of a steam crane with a having locking gear and pulling handle. It may tion of other hydraulic machines is costly. The locomotive engine for common roads. The crank also, when required, be arranged for being drawn whole of the Noria is made of iron, and the chain shaft drives directly a counter shaft immediately by a horse, and seems well adapted as a very port- and buckets so constructed, that it can readily be behind it, which is at the same time the shaft of able fire engine, or as a steam pump. It is a ques-lengthened as the water sinks in the well or tank. the winch barrel. From this counter shaft a pitch tion whether a rotary motion is not less distressing Messrs. Warner also exhibited a large selection of chain drives the main axle, or rather one of a to the arms and chest than the ordinary up and their pumps and garden engines, their quadrant pair of bevel wheels of a "jack-in-a-box" motion down pump-handle action, which ought only sluice valve, which we described and illustrated on that axle, which gear, though strong, is worked to be resorted to when rotary motion cannot con- some months since, also their provincial fireinto a very small space between the firebox and veniently be used. A 24in. California pump, with engine, a new pattern and one calculated to meet the off-driving wheel. The bevel next the fire- rotary motion on an iron tank, is another adapta- the requirements of small villages, gentlemen's box is keyed fast on the axle, and that outside tion of this useful pump for smaller occupations mansions and farms. It is comparatively light, next the off-wheel is in one with the wheel; the and premises. To be a valuable agricultural ma-portable, and easily removed from place to place motion of both wheels is therefore under ordinary chine, the water may, by means of a two-way by two men. The pumps are of equal capacity to circumstances equal, but when unequal resistance cock, be drawn either from the tank itself, or by the London Brigade fire-engines; but being contakes place a certain play is allowed (as in all hose from a pond or cistern. Another useful apcases where this gear is used) between the driving plication of the California pump with rotary mowheels. As it would be inexpedient to leave the tion is exhibited by this firm in a 24in. pump on engine always at the mercy of this compensating frame, to be worked by hand or power. Still arrangement, the near wheel is releasable, as in another useful arrangement is their force pump on all Aveling's engines, from the axle, by with- barrow for farm or garden purposes. Among the drawing a pin in the box, and the off-wheel can numerous hydropults, or whatever the various be clamped on to the axle-supposing such a names of practically the same thing may be, a course necessary to get out of a hole-by placing novelty in the arrangement for working such pumps a clutch on the outside of the wheel over the may be mentioned, called the model garden engine, grade pin, and catching the spokes of the wheel. with lever and vibrating fulcrum standard. It is The winch barrel moves free on the counter certain that this motion is easier and handier than shaft till thrown into gear at the same time that the direct pull and push action ordinarily used the locomotive motion is thrown out, when only in these little pumps. The same principle is apthe crane is required. The hoisting chain passes plied to the iron cottage pump of this firm, a neat under the boiler and up over the gib which is and ornamental article, and very cheap. We also simply formed of two T-irons, and pivoted on a noticed the American pitcher pump, as used for ball and socket joint capable of turning in any Norton's patent tube well-boring apparatus, and desired direction. The steering chains are taken which may be worked at a good speed with little reversely on to a horizontal shaft under the boiler, labour, as the stroke is rather short. The water which is worked by a worm and pinion, which can easily be let out of the barrel to prevent can be managed from the footplate. So convenient freezing. are all the arrangements that the whole is under the control of one boy, who did excellent service with the engine both in the trial field and the show-yard. Messrs. Aveling and Porter also ex structed with a longer leverage, eight men will throw as much water to as great a height as twelve men working the double-barrel 5-inch brigade engine, viz., fifty-five gallons of water 90ft. high. The tank containing the pumps is filled with water to keep it steady and firm when in use, is readily removed from its carriage, and the engine can be worked as soon as the hose pipe is connected to it. The trials of the horse ploughs were carried on under difficulties, owing to the baked and hardened soil upon which they had to operate. The manufacturers who competed were:-Messrs. J. Cooko and Co., Lincoln; E. Page and Co., Bedford; R. Hornsby and Son, Grantham; James and Frederick Howard, Bedford; W. Ball and Son, Rothwell; and Ransomes and Sims, Ipswich. The work done by Messrs. Ransomes and Sims' plough was straight and cleanly cut; that by Messrs. Howard's plough was extraordinary for soundness and accuracy to the eye; while that done by Messrs. Cooke's plough was well-turned and good. These Messrs. Warner and Sons, of Cripplegate, Lon-ploughs, however, are only for exceptional work, don, exhibited their new annular sail self-regulating wind engine, the principle of which will be seen by the accompanying cut. These engines are and the expenditure of horse-power required must either resolve itself into a fancy outlay, or if any profit on their use be required, they must be used |