840 Mr Whitelaw's Description of 



In order to get a very large pulley put into, or taken out of the 

 machine, the rail x must be taken away, by unscrewing the 

 bolts which fix its ends. In the bracket gg gg, each of the 

 parts which hold the pins i i has a slit in it, so that, by un- 

 screwing the nuts ?/ ?/, the pins may be shifted to any end of 

 the slits. One of these slits is seen in Fig. 2 ; it has a check 

 round it to receive a shoulder formed upon the pin. In the 

 frame II mm each of the parts which hold the bushes for the 

 pins i i, has a slit formed, so that the bushes can be fixed on 

 either end of it ; there are cutter holes placed so that the 

 bushes can have other positions, besides at the ends of the slits. 

 When the bushes are not fixed at any of the ends of the frame 

 II mm, a gib, as shewn in Fig. 2, is passed through a set of cut- 

 ter holes ; after this the brasses are brought up against it, and 

 fixed by means of the same cutter which fixes them at the ends 

 of the slits. By having the slits for the pins in the bracket 

 gggg, and the slits for the bushes in the frame II mm, allows 

 the rails upon which the bracket gggg slides, as well as other 

 parts of the machine, to be made much shorter than they could 

 be made without them, and some sizes of pulleys could not be 

 ground at all without these slits. The use of the slits in the 

 bracket gggg is to allow the mandril c c in every position to 

 work clear of the part of this bracket, which has an upright 

 direction in Fig. 1. The cutter holes in the frame II mm 

 must be fitted, so that, in whatever place in the slits the bushes 

 are shifted to, the rails II and mm will have an upright posi- 

 tion, in a view, as per Fig. 1 ; and when the pins i i are shifted 

 to the different ends of the slits, in the bracket gggg^ from 

 what they are shewn in the Figs., these rails of the frame II mm 

 must have an upright position, in a view, as per the side eleva- 

 tion. It will be seen that Fig. ^ is not a complete end view, 

 but is only intended to shew some of the parts. 



If the smallest speed of a cone was made in the form of a 

 pulley, with a flanch cast inside of its rim close to one end ; 

 and then, if the next larger speed was cast without arms, but 

 having two flanches, one at each end of its rim, the parts now 

 spoken of could be fixed together so as to form a cone of two 

 speeds, by means of bolts passing through the flanch on the 

 ^mall speed, and one of the flanches on the large speed. On 



