80 FERGUSON'S LECTURES. 



lies upon beams in the floor Y Y. The top part of the 



spindle above the bush is square, and goes into a square 



hole in a strong iron cross abed, called 



the rynd ; under which, and close to the 



bush, is a round piece of thick leather 



upon the spindle, which it turns round at 



the same time as it does the rynd. 



The rynd is let into grooves in the under surface of 

 the running millstone G (p. 79.) and so turns it round 

 in the same time that the trundle is turned round by 

 the cog-wheel D. This mill-stone has a large hole 

 quite through its middle, called the eye of the stone, 

 through which the middle part of the rynd- and upper 

 end of the spindle may be seen ; whilst the four ends of 

 the rynd lie hid below the stone in their grooves. 



The end T of the bridge-tree T S (which supports the 

 upper millstone G upon the spindle) is fixed into a hole 

 in the wall ; and the end 5 is let into a beam Q R called 

 the brayer, whose end R remains fixed in a mortise: 

 and its other end Q hang's by a strong iron rod P which 

 goes through the floor Y Y, and has a screw-nut on its 

 top at O ; by the turning of which nut, the end Q, of 

 the brayer is raised or depressed at pleasure ; and 

 consequently the bridge-tree T S and upper mill-stone. 

 By this means, the upper mill-stone may be set as close 

 to the under one, or raised as high from it, as the 

 miller pleases. The. nearer the millstones are to one 

 another, the finer they grind the corn, and the more re- 

 mote from one another, the coarser. 



The upper millstone G is inclosed in a round box H, 

 which does not touch it any where ; and is about an 

 inch distant from its edge all around. On the top of 

 this box stands a frame for holding the hopper k k, to 

 which is hung the shoe / by two lines fastened to the 

 hind-part of it, fixed upon hooks in the hopper, and by 

 one end of the crook-string K fastened to the fore-part 



