Rock Island daily Argus. (Rock Island, Ill.) 1886-1893, 1892-10-10
HOW FLOUR Is MADE.
A JOURNEY THROUGH A MODERN
ROLLER PROCESS MILL

wheat Il First Broken by Rollers and
Gradually Crushed into Flour By Sew
oral Series OF Other RolIers-Separat-
ing the Fine Flour from Bran.
Let us enter a roller process mill and see
its devices for reduction and separation at
work. First of all we are shown the ma
chimes which, by means of sleeves and air
blasts, remove from the wheat its admix-
ture OF cookies, tares, ships and dirt. Next
come the securing machines, stoutly
framed and covered with cases OF perfo-
rated cast iron. These are fed from the
cleansers we have just seen, and their
duty is to cut off the head of the grain,
leaving it in a perfectly secured and pol
ished condition for reduction by the roll
ers Some millers prefer cases made of
very heavy rolled wire of square sections,
whose sharp. impinging edges exert a
greater effect than is possible with wire of
ordinary round form.
Cleaned and prepared, the wheat is now
ready for the first pair of rollers. These
are usually twenty-four inches long, nine
inches in diameter and bear twelve cor
rugations to the inch. In contour these
corrugations resemble the teeth Of a saw.
and vary with the kind of wheat to be
treated. For the hardest varieties of grain
they are not so sharp as for soft wheats.
To prevent their fnterlocking with each
other they wind around the rollers In a
gentle spiral. To avoid splintering the
bran they are no nearer than is absolutely
necessary to accomplish the work of each
reduction They are completely boxed in
so as to be breast high, and through lit
tie glass window the miller can see how
their work is going on. AS a rule the
rollers are Of chilled iron. tough enough
not to need recutting until after two to
five years use.
Porcelain rollers give satisfactory re-
suits, but their employment is limited
Chilled iron is easier to manufacture and
repair AS we watch the first pair of roll
ers at work we observe that one of them
revolves faster than it's mate, SO that a
grain of wheat caught on the projection of
slow roller is stretched out or unfolded
by the projection of the quick one This
action it is which opens the grain SO as to
shell ont the middlings without at the
same time making more than a trifling
quantity of flour. A point just here to
which the miller pays particular attention
is keeping these rollers at the right dis
tance apart. If too far from each other
they take no hold of the wheat. II too
near they mash it into flakes which resist
the rollers work.
When wheat has passed through the
first pair Of rollers the product is con-
Quoted to a scalping reel. This reel is
revolving cylinder, covered with wire, hav-
ing about 324 openings to the square inch.
AS the meal is carried up it's ascending side
the flour and middlings fall through. The
axis of the cylinder is inclined, and the
portions of wheat stock which cannot get
w ind hair
way to the cylinders end or tail, there
to be taken to second pair of rollers for
second reduction, in principal essentially
the same as the first. To the second pair
of rollers succeed others until fifth or
even a sixth pair is reached. Each pair
has more corrugations to the inch than its
predecessors, and has it's two rollers placed
nearer together.
In following the partly broken wheat to
the second pair of rollers we left behind
us for a moment the flour and middlings
due to the first pairs action. These two
products, the miller reminds us, were de
livered by the scalping reel as n mixture.
He now submits them to a boiling reel, q
frame clad with silk having hundreds or
thousands of apertures to the square inch.
This reel is cylindrical 4 form much pre-
ferable to the six sided shape of old pat
terms. Through its apertures the flour
readily passes, leaving the middlings in
the reel In this way scalping and boiling
reels follow up each successive pair of
rollers, their meshes gradually becoming
finer and finer How much finer depends
upon the character of the wheat and the
general conditions under which mill is
operated. AS q rule the silks run one
number or size finer at each reduction.
We are shown a variety of cloths, all of
European make, ranging from SO to 2S, 900
meshes to the square inch
The durability of these silks is astonish-
ing With soft wheat a reel will serve six
or seven years and remain in good condi-
ton. Wheat attracts moisture so readily
from the atmosphere that it's dampness
foretells a coming storm as certainly as a
falling baron ter. On muggy days boiling
is so much retarded that if possible the
miller slows down operations.
Under his guidance we now retrace our
steps to where we left the boiling reels de-
livering their middlings. We are now to
see what becomes of them. Mixed as they
are with particles Of bran, fiber and other
impurities, they go to a separator, con-
trived upon a principle as simple it is
effective.
In windy weather, if we inspect the dust
borne to the window sills at the various
levels of a tall building, we find a decided
difference in it's quality The dust which
has risen to the top story is much finer
than the dust deposited at the ground floor
The wind has carried light particles fur
ther than heavy ones This action is imi-
tated in the aspirators and purifiers of our
mill A sharp blast of air is directed
against the mixture of middlings, bran
and fiber. AS the finer and lighter frag-
ments can be blown further than the
heavier and coarser, they are separated
into their special boxes or chutes. Puri-
fiers are made in variety of designs. These