382 HIGHWAYS AND HORSES. 



a cylinder of the diameter of the intended ring of the 

 wheel, after which it was shaped, mortised, and fitted 

 to the spokes as before described ; such kind of wheels 

 are still made, but the boiling process greatly weakens 

 them, hence wheels so made are not much in common 

 use ; they are, however, neater and look much better 

 than any wheel which can be made by the common 

 method ; the drawn iron tire is always made use of 

 for such wheels. 



The boxing of a wheel and adapting the axle-tree, 

 is done usually by the coach or tire-smith. The box 

 for a wheel consists of a hollow, conical tube of iron, 

 furnished on its outside with two or three square 

 projections, which have the effect of giving it a key 

 when mortised through the nave of the wheel. The 

 box is w^ell polished on its Inside, and the axle-tree is 

 accurately formed to fit Into it, with sufficient play to- 

 admit of oil being introduced to modify the friction. 



The external ends of axle-trees, which pass through 

 the boxes, are generally formed Into screws to which 

 are adapted nuts of sufficient size to cover completely 

 the external edges of the boxes of the wheels, which, 

 with a llnch-pin that passes through the axle-tree arm, 

 completely secures the wheels to their work. The screws 

 upon which the nuts are fitted are cut reverse ways. 



The mail axle Is of a different construction, and owes 

 its safety to four bolts, which pass completely, first 

 through the iron shoulder on the axle,*and then through 

 the nave of the wheel and the outer plate, these bolts, 

 having a square shoulder on the inside of the nave,, 

 with screws and nuts on its front. The box is made 

 like other boxes, except that it and the nave are com- 

 pletely covered at their outer end with a solid and 

 broad cap of iron. The axle-tree, too, is formed to fill 



* This iron shoulder, of course, revolves into the nave. 



