The saw is of great antiquity.
known to the Egyptians and other early nations, and traces of
its early use have been discovered in nearly every country where
the arts and sciences have made the least progress. In
England, Sheffield, the metropolis of our manufactures in steel,
has had the saw-making almost entirely to itself, many hundreds
of skilled and intelligent artisans being continually employed
in this important branch of industry.
In former times, there was little variety in the
shape of the saw, which in general appearance strongly resembled
the bow-saw used by the carpenters.
At the present day, however, the different kinds
of saw-such as the cross-cut-saw, pit-saw, frame-saw,
ripping-saw, hand-saw, panel-saw , compass-saw, and sash-saw are
almost endless; the making of each kind of saw forming, as it
were, a distinct trade or occupation.
The common description of saw is made of rolled
iron plates, hammer hardened, and planished upon an anvil,
whereby they attain the requisite degree of stiffness and
The better kinds of saw are made of shear or
cast steel. The steel, which has been prepared in thin sheets,
is cut, as shown in our first illustration, into strips of the
required size, which after the edges have been smoothed and
leveled by careful filing, are handed to the grinders to roughly
prepare them for cutting the teeth.
Much has been said respecting the unhealthiness
of the grinding processes, but the saw-grinding is stated to be
far less detrimental in its effects upon the health of the
workers than are the other descriptions of grinding.
Dr. J. C. Hall expressly states saw-grinding to be
a comparatively healthy occupation. “The men,” says he, “stand
at their work, and, consequently, the lungs are not so
compressed as when the grinder, sitting on his horsing, bends
forward for many hours each day in other branches of the trade.”
The real danger-one, in fact, from which none of the grinding
processes are exempt-consists in the flying of the grindstones. The stone, while revolving at a fearfully rapid rate, will
sometimes fly in pieces, the fragments crushing and destroying
everything in their way.
These accidents occur from flaws in the
stone, or from the defective manner in which it is fastened on
the axle. Fixing the stones on the axles by means of iron
plates, instead of wooden wedges, which are liable to swell from
moisture or the heating of the iron axle, is considered to be
the best safeguard against such accidents.
In America the same
processes are performed by machinery; but, according to Mr.
Ibbotson, a Sheffield manufacturer, the operatives of the town
will have nothing to do with work thus prepared. If this
statement be true, it is to be regretted, because it will
gradually give the foreign workman an immense advantage over the
When the strip of steel has been ground smoothly
on both sides, it is given to a workman, who, by means of a
die-cutter in a fly-press, rapidly cuts the teeth, one or more
at a time, with astonishing precision. This process forms the
subject of our second illustration.
After one of two subsequent
minor processes, the saw is again hardened and tempered, and
then it is handed to a grinder to be ground for the second time.
The grinding, both on this and the previous occasion, is
performed with the assistance of water, which prevents the
particles of dust rising from the stone, as in razor or knife
grinding. But whether the process be wet or dry, the grinder is
exposed to the danger of inhaling air laden with fine dust while
“hacking” or “razing” the grindstone.