THE MAIL AXLE. 383 



the box and press up close to this iron cap. The round 

 iron shoulder is made and welded to the solid axle-arm ; 

 this shoulder works in the box of the nave. This and 

 the outer cap have four perforations, through which the 

 iron bolts are driven, and which also pass through the 

 nave of the wheel with their screws presenting them- 

 selves through the iron cap at its outer end. When these 

 bolts are all adapted and in their place, four nuts, of 

 about an inch and a quarter square, are screwed on to 

 them ; the shoulders of which are supplied by the iron 

 cap which secures the axle-tree in the box, and holds up. 

 the wheel more firmly to its work than any other plan 

 now adopted. By this method no dirt can penetrate 

 to impede the motion, or create friction, as the end of 

 the cone of the working axle is completely enclosed,, 

 and when once the wheel is put on and properly oiled, 

 it is found to go on in its work for a considerable time. 

 This axle is the celebrated "mail axle," which is used 

 in all coaches, mail phaetons, and properly built Stan- 

 hope gigs ; and, of all axles that have been invented, 

 none is stronger, less likely to get out of order,, 

 or more drag-like in appearance. This, and Col- 

 linge's patent axle, are about the only two axles in 

 general use. There are three parts in the axle, the 

 two arms which pass into the naves of the two wheels, 

 and the bed or centre part which connects the two. 

 arms. It is partly on account of the ingenious way in 

 which lubrication with oil is effected, that Collinge's. 

 patent axle is so much employed. Besides the me- 

 chanism for connecting the axle with the wheel, there 

 is the little cup for holding oil, and as the wheel rolls 

 along, the oil is pumped or drawn out of its receptacles, 

 and made to lubricate the adjacent surfaces. It must 

 be understood that there are three kinds of axles in 

 existence ; these are the common or plain axle, the: 



