722 Report on Implements at Preston. 
There were four exhibitors of novelties in small flour mills 
for hand or horse power. Although these implements are of 
little use to an English farmer, unless they can be also used for 
kibbling or coarse grinding for cattle, they are of great value to 
colonists and to small farmers in France and Italy, and are still 
used to some extent in the remote districts of Scotland, Ireland, 
and Wales. The chief characteristic of Messrs. Nicholson and 
Sons "Sampson" Corn Mill, No. 172, is that the concave as 
well as the cone of grooved steel revolves. Their rotation is in 
the same direction and on the same spindle ; a sun and planet 
gearing causes the cone to make 400 and the concave 57 revolu- 
tions per minute. This would be equal to 343 revolutions of 
the cone, if the concave were stationary. The concave can be 
made to revolve in the opposite direction, and one would have 
supposed that the same result might be obtained with less 
power by driving the cone at 300, and the concave in the oppo- 
site direction at 44 revolutions per minute. The ma.kers, 
however, state that a much softer sample of flour is obtained by 
making the concave follow than by keeping it stationary, or 
making it revolve in the opposite direction. The revolution of 
the concave prevents any undue wear of any part of its surface. 
The wear is thus regularly distributed over the whole surface 
of both the grinding parts. These mills work easily, and since 
the abolition of the oppressive grist-tax in Italy, many of them 
have been sent to that country, fitted with hand gear, for domestic 
use among the peasants. 
As a general rule stone mills are horizontal, and metal mills 
are vertical ; it is singular that the two sorts of new mills 
that remain to be described are both of them exceptions to this 
rule. In No. 454, Messrs. Jeffery and Blachstone's " Stamford " 
Stone Mill, the stones are vertical. Hitherto there has been a 
serious objection to vertical stones from the caking of the flour 
upon the casing of the mill, often to the extent of one ^inch in 
thickness, where it was liable, if left, to ferment, in consequence 
of the heat developed in the grinding, and subsequently to drop 
off and spoil the meal. This is obviated in the new mill by 
fitting the brushes on the back and on the periphery of the 
running stone ; these act upon the internal surface of the 
casing, and by their revolution keep a current of air moving 
round between the stone and the casing. These brushes not 
only act as fans to keep down the temperature, but also serve as 
lifters to raise the product as it is formed to a spout sufficiently 
high to deliver it into a sack or flour dresser standing on the 
floor of the building. The exhibitor stated that linseed can 
now be satisfactorily ground by this mill. 
In Messrs. Richmond and Chandler s Corn Crusher, No. 2220, 
