WHEEL. 



Some of (kefe inventors even pretend that aU thefe ad- 

 vantages are combined in one axle-tree ; but the generality- 

 extend to the advantage only of retaining a fupply of oil, 

 and remaining perfeft to a confiderable length of time. The 

 common fort of axle-tree and box, which is moft generally 

 ufed, is fimple and cheap in comparifon with the others. 



Common Axle-tree. — The arms of the axle-tree are made 

 round, but rather of a conical form, flrongeft at the back or 

 flioulders, tapering to the linch end, which is fcrewed for 

 a nut, and alfo has a fmall hole for a linch-pin, which 

 prevents the nut from coming off: at the body-end is 

 a waflier or collar for the back of the wheel-ftock to wear 

 againft. The box is made of llieet-iron, proportioned in 

 fubftance to the weight or fize of the axle-tree, having the 

 edges of the plate, of which it is formed, vcelded in a ridge 

 which projefts on the outfide ; this fecures the box in the 

 nave of the wheel, and prevents it turning round therein. 



The nut which fcrews on the end of the axle-arm has a 

 broad face to lie flat againft the wheel, and is tapped or 

 fcrewed to receive the fcrew-end of the axle-tree. Each of 

 thofe nuts muft turn on the fcrew the fame way the wheel 

 goes, and muft have a notch for the linch-pin to pafs 

 through, for the purpofe of fecuring the nut from turning 

 off. 



The box is what, of the axle-tree, wears moft, and is fre- 

 quently obliged to be refitted to the arms ; otherwafe they 

 give to the wheel while in ufe an unfteady motion, and foon 

 exhauft their ftock of greafe. 



Thofe that are well fitted will contain their fupply for 

 about one week with regular ufe, or a journey of one hundred 

 miles. They wear at the rate of one fet of boxes to every 

 two fets of wheels, and require in that time to be twice or 

 thrice taken out of the wheels and refitted to the axle-tree 

 arms. 



Axle-trees with FriBlon-Wheels. — Thefe were invented by 

 Mr. Garnet, at leaft the beft kind, which are made in a very 

 ingenious manner. The wheel-box is made much larger 

 than the axle-tree, in fuch manner that the fpace all round 

 between them may receive a number of rollers which fill it 

 up. ( See a defcription in the article M.l'Lh-Work. ) Mr. Gar- 

 net had a patent in 1784, and for fome years manufactured 

 great numbers ; but being very expenfive, they fell into 

 difufe, although very complete. This invention has been 

 lately revived by Mr. Panter. 



The Patent Anti-Attrition Axle-tree and Box The pro- 



pofed advantages of this axle-tree are, eafe of draft by dimi- 

 nution of friftion ; the retention of oil to fupply a month's 

 ufe ; the eafe with which it is replenifhed without taking 

 off the wheels ; the great fecurity for the wheels, which it 

 prevents from coming off, and the carriage from over- 

 turning, if even the arm of the axle-tree fhould break ; and 

 their durability, and even improvement by wear. Thofe 

 axle-trees, if made with the fecuring-coUar, for the wheels 

 need no nut or linch-pin, as is generally ufed, but the wheel 

 may be taken off and put on as eafily as thofe on the 

 common principle. 



Thefe axle-arms are reduced at the bottom from a per- 

 it6t round, and grooved, to receive two fmall rollers, on 

 which the weight of the carriage is borne, and which greatly 

 facilitates the motion, in the fame manner as blocks of ilone 

 or timber, which require to be removed by the affiftance of 

 rollers. Thefe rollers form the outer circumference of the 

 axle-trees at bottom, which are reduced to give a bearing 

 only on them. A circular box or ciftern is provided to con- 

 tain a fupply of oil ; it is clofely fitted to the back of the 

 inner end of the wheel-ftock, and fixed by three bolts. 

 The oil is here contained within three circular receffee, and 



Vol. XXXVIII. 



oozes through fmall channels on the arm of the axle-tree, 

 which it feeds for a confiderable time. This oil-box is 

 made of caft-metal, and has a cap projefting behind over 

 the axle-tree, which prevents the dirt from getting into the 

 box. This axle-tree is alfo provided with what is called 

 the wheel-fecurity, or ftrap-wafher. It is an iron collar, 

 fitted on the external part of the wheel-flock, and confined 

 between the refervoir and ftock, lying as it were in a groove, 

 fo that the coUar cannot come off. This collar has two 

 lugs or ftraps extending backwards fome diftance along 

 that part of the axle-tree which is bedded in the wood-work, 

 where it is fixed by a nut-fcrew. By means of this ftrap- 

 wafher, the wheel is fecured to the bedded part of the axle- 

 tree ; and fhould the axle-arm vrithin the wheel break, the 

 wheel will continue to aft. 



The cap of this axle-tree is alfo fixed on the out- 

 fide part of the wheel-ftocks ; by the fame three bolts 

 which faften the oil-box, and by means of a fcrew-plug in 

 the cap, the axle-tree and refervoir are replenifhed with oil. 

 The box is of the fame form as the common box, only 

 made of a very hard durable metal, of a confiderable 

 thicknefs, and is made in proportion to the weight of the 

 carriage. 



Collinge's Patent Cylinder Axle-tree and Box. — Thefe axle- 

 trees have been a confiderable time in ufe, and their advantages 

 have been proved in the length of time they wear, in the filent 

 and fteady motion they preferve to the wheels, in the 

 advantage of retaining the oil to profecute a journey of two 

 thoufand miles without being once replenifhed ; and laftly, 

 they are very durable, and but little fubjeft to be out of 

 order. 



The axle-tree arm is made as perfeftly cylindrical as pof- 

 fible, and of a peculiar hard fubftance ; the middle of the 

 cyhnder is reduced, to contain the oil neceffary to feed the 

 axle-trees ; fo that the two bearings are at the two ends of 

 the axle, which has an internal fhoulder, againft which the 

 inner end of the wheel-box takes its bearings. Behind this 

 fhoulder is a deep groove for a wafher to preferve the 

 oil, and prevent noife in its ufe ; alfo a rim, or hollow 

 box, on the collar of the axle-tree, which overlaps part 

 of the inner end of the wheel-ftock to keep out dirt, 

 and anfwer the ufe of a cuttoo. The extreme end of the 

 arm is double-fcrewed, to receive two nuts for fecuring the 

 wheel : the one fcrew turns the way of the wheel ; the 

 other the reverfe, and is meant as an additional fecurity. 



The box is made of a very hard metal, nicely polifhed, 

 and fitted to the arms, having a circular recefs all round at 

 the end neareft the carriage, for containing there a fupply 

 of oil. The box is longer than the part which bears on 

 the axle ; and the projefting part beyond the bearing at each 

 end is bored out larger than the arm. The back projeftion 

 fits clofe to the rim of the collar, which it covers : the 

 fore one projefts outwards beyond the furface of the wheel- 

 ftock, and is fcrewed on the infide to receive the fcrew of 

 the cap. 



There are many other patents for axle-trees to wheels ; 

 but as few of them have come into ufe, we fhall only notice 

 Meflrs. Flight and Brook's patent axles. The axle is fixed 

 fail to the nave of the wheel, by palling through it. This 

 axle turns round within the wheel-box ; whereas in others 

 the wheel-box turns round upon the axle. 



The axle is cylindrical, and is received into a cylindrical 

 box or tube in the end of the iron axle-tree, which is firmly 

 bolted to the underfide of the timber of the carriage. To 

 hold the axle in its place, and prevent it from drawing out 

 of the box, the end of the axle is reduced to a knob or 

 button, which adheres to the end of the axle by a fmall 

 3 A neck. 



