Modern Improvements in Corn-Milling MacJiinery. 107 
the meal to appear in a " flakey " condition rather than in the 
round and detached condition in which the millstone delivers it. 
If it were attempted to dress out the flour from this flakey meal 
by means of the ordinary reel, some of the " flakes" would pass 
out at the tail of the reel, although only a very slight friction 
was required to make them fall into flour. The invention of 
the " centrifugal " flour-dressing machine overcame the diffi- 
culty. It consists of either a cylinder or hexagon, of from two to 
four feet diameter, covered with silk cloth, revolving at a moderate 
speed, and having a central shaft furnished with arms to which 
blades or beaters are attached set within a short distance of the 
interior of the silk surface. These beaters revolve somewhat 
rapidly, and throw the meal to be dressed or sifted against the 
silk. The flour passes through the meshes, and the residue goes 
on to the tail of the cylinder and so out of the machine. The 
slight friction is sufficient to disintegrate the little flakes. As 
these cylinders are very much shorter than the old reels, much 
space is saved in the mill by their employment. 
An important point remaining to be noticed is the question 
as to the comparative amount of flour which can be extracted 
from a given quantity of wheat by one process or the other. 
Under the millstone system it may be said that about 75 per 
cent, of the original cleaned wheat was an average yield ; under 
the roller system practice varies very much ; in the best mills 
and from the dryest and best wheats 75 per cent, is to be 
obtained, but it may be said that from 68 to 72 per cent, has 
been the more general result. It must, however, be remembered 
that the 75 per cent, of millstone flour contained a proportion 
of what is now ranked as offal, and that the smaller percentage 
of roller-made flour is of much better quality than the mill- 
stone flour. 
Under the low-grinding millstone process, nearly the whole 
of the flour yielded by the wheat ground was of one quality, 
alterations of quality of flour being attained by varying the sorts 
of wheat employed. Under the gradual-reduction process very 
many qualities of flour are obtained from the same wheat. The 
best flours made from wheat even of cheap and inferior quality 
may be better than millstone flour made from the most expen- 
sive and finest wheats ; while from appropriate wheats a large 
percentage of fine flour selling at a high comparative price may 
be extracted, leaving the remainder equal in quality to the whole 
quantity of flour produced by the millstones. It is the better 
quality and higher value of the flour made by the gradual reduc- 
tion process that has induced mill-owners to expend in building 
and refitting mills sums that have been estimated at several 
millions sterling. The earlier adventurers, even with the draw- 
