552 Report of the Judges of Implements at Norwich. 
by means of clamping screws, and the rotating stone or runner 
(e) to a rotating shaft ; the corn is placed in the hopper (a) or 
the top of the casing, and is thence conveyed to the eye of the 
fixed stone, through the shoot (b) and feed spout (c). This 
shoot is provided with a riddle, to prevent any substance other 
than corn from entering the mill ; but in case a hard substance, 
as stones or nails, should by chance not have been prevented, 
springs are supplied, to allow the stones to move apart, and 
make way for the hard substance to pass. On reaching the eye 
of the bed-stone, the grain comes in contact with a worm 
attached to the mill shaft, delivering it to the furrowed grinding 
surfaces, there reduced to the required consistency, and dis- 
Fig. 22. — Cross Section of Messrs. Jeffery and BlacJcstone's Corn 
Grinding Mill, No. 2321. 
charged into the case. The running stone (Fig. 22, e) in this 
mill is fitted with brushes, which act upon the internal surfaces 
of the casing ; and, by their revolution, keep a current of air 
moving round, between the stone and the casing, by which means 
the apparatus and the meal are kept cool, and the meal prevented 
from any adhesion, thus securing it against all harm which 
might be caused if it were not kept clean. The brushes, acting 
as lifters, also raise the meal as it is formed to the elevated 
spout (f), which is high enough to deliver into a sack, bin, or 
flour dresser, or any other receptacle on the floor of a mill. By 
