AN IMPROVED MANUFACTURE AGRICULTURAL AND OTHER IMPLEMENTS
Year: 1874

page_text: LETTERS PATENT to Frederick Curtis, of Boston, in the County of
OF
Suffolk, and State of Massachusetts, in the United States of
America, for the Invention of "AN IMPROVED MANUFACTURE
AGRICULTURAL AND OTHER IMPLEMENTS."-A communication from
Archibald Mac Martin, residing at New York, in the County
and State of New York, in the United States of America.
Sealed the 30th October 1874, and dated the 6th May 1874.

page_text: "IM-
sincerely declare that I am in possession of an Invention for an
PROVED MANUFACTURE OF AGRICULTURAL AND OTHER IMPLEMENTS," which
Invention I believe will be of great public utility, that it is a communi-
cation to me from Archibald Mac Martin, a person resident at New York,
in the County and State of New York, in the United States of America,
and I do hereby declare the nature of the said "Invention for Improved
Manufacture of Agricultural and other Implements," to be as

page_text: requisite when properly extended in length and reduced in thickness to
secure a blade firmly to a handle, and is avoided the labor incident to
that manufacture in which riveting and welding an independent jaw or
lip to the main body of the implement is necessary, as heretofore; but
what is also of great importance is obtained an entire implement com-
posed of one homogeneous piece of metal.
In these experiments it has been governed by a well known fact that
steel is very difficult to weld at any temperature with whatever adjuncts,
and that two pieces cannot under any circumstances be welded together
except at such a high heat as need not practically be used in rolling or
forging articles of any degree of thinness. Therefore after having
produced the lips in rough as stated, the steel may be licated to the
requisite degree for subsequent manipulations without danger of their.
becoming welded when hammered or rolled together.
Having roughly fashioned the block of metal to the form shown in
Figure 3 of the Drawings, the next preceedure is to reheat the blank and.
then to reduce the whole to the requisite degree of thinness required
for the sum of the two jaws, which latter, though in reality sundered and
independent, is treated as a solid prong while reducing, and afterwards
spread them apart.
The blank at the termination of the last described manipulation will
present the appearance shown in Figures 4 and 5 of the Drawings, the
dotted lines in the latter figure representing the conical socket in the
blade, and the line e the separation of the jaws or lips c, c, the said
socket remaining substantially intact throughout the subsequent
treatment.
As the jaws c, c, have now been reduced to the minimum general
thickness and the blade a must be further reduced, it is desirable to
effect this and the former reduction of the blade in as speedy and
economical a manner as possible; and to reach this end hammering,
which is tedious and expensive, is preferably avoided, and recourse to
rolling is had, which effects the result with rapidity and perfection. For
this purpose a pair of rolls f, f, is employed mounted in suitable
standards g, g, and projecting at one end beyond the latter, as shown at
h, h, in Figure 6, in order to be free and unencumbered by the standard,
and to be able readily to introduce this object at any desired augle or
position.

page_text: The preliminary rolling of the blank up to the stage shown in Figures
4 and 5 may be effected between the portions f, f, of the rolls; but as
the blade a is to be further reduced in thickness, and it is essential that
no further reduction of the shank or the swell about the socket & should
take place, the unencumbered ends h, h, of the rolls are employed to
complete this final reduction of the blade, and the said blade is passed
through the rolls at an oblique angle to its longest plane, and work
closely up to the swell or boss which enclosed the socket, as shown by
the diagonal lines in Figure 7 of the Drawings, this rolling being done
uniformly upon each side of the boss or from both sides of the blade, by
which means the triangular form of such boss is preserved.
If it were found in practice that the combined thickness of the two
jaws need be no more than the thickness of the blade, then the last-
named reduction would not be necessary, and the original reduction
would be carried far enough through ordinary rolls to correspond to the
desired thickness of shovel blade. But that the sum of the thickness of
the jaws may be if necessary considerably greater than that of the blade
(as is generally the case in all kinds of shovels), this additional reduction.
is provided for.
It may further be found in practice desirable and economical to
produce two blanks in one piece, as shown in Figure 8 of the Drawings,
and separate them on the dotted line, cach half being then treated as
herein-before described, or also to produce a double blank as shown in
Figure 9 of the Drawings, and after splitting the two tongues roll the
whole out at once to the general thickness required for the double thick-
ncss of the jaws, after which the double blade can be cut in two and
each half treated as before described by the oblique rolling operation.
It will also be apparent that the comparative strength of either jaw
may be varied with reference to that of the other, by simply causing the
original separation of the projection on the blank, as well as its corre-
sponding extension into the body of the blank, to be made on one, or
other side of the medial plane. This relative strengthening of one of
the jaws would extend also to the junction of this jaw with the shovel
blade, and thus the scope of strengthening the otherwise weak points is
almost unlimited. By this method is produced an implement which
possesses great strength in what is now its weakest part, viz., at the
point where one tongue or lip is welded to the blade.

page_text: Although this Specification refers to the production of a shovel, it has
been for the purpose of explaining this mode of procedure, as it will be
apparent that the principle of this Invention is applicable to various
other implements, and it is desired in no sense to be restricted either in
detals of method of carrying out such. Invention or in the particular
article in which it is to be exemplified, so long as it is restricted to what
is believed to be its primary feature, that is, producing shovels and
kindred articles by forming their two lips or handle enclosing jaws from
the blank from which the blade is produced, or otherwise taking
advantage of the fact that steel or "homogeneous metal" once separated
will not weld together again at temperatures requisite to working it up
by forging or rolling.