IMPROVEMENTS IN BORING AND SAWING ROCKS AND OTHER MINERAL SUBSTANCES, AND DRESSING STONE
Year: 1874

page_text: LETTERS PATENT to John Macintosh, of the Strand, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN BORING AND
SAWING ROCKS AND OTHER MINERAL SUBSTANCES, AND DRESSING STONE."
>
PROVISIONAL SPECIFICATION left by the said John Macintosh at the
Office of the Commissioners of Patents, with his Petition, on the
the 14th May 1874.
I, JOHN MACINTOSH, of the Strand, in the County of Middlesex, :
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN BORING AND SAWING ROCKS AND OTHER MINERAL SUBSTANCES, AND DRESSING
STONE," to be as follows:-
This Invention consists in the application of chilled or other hard
metal cutting nibs or points to the boring or drilling tools used for
boring rocks, such cutting pieces being applied also to saws and dressing.
tools for stone, the object being to substitute these cutters for the
:

page_text: diamonds at present in use as applied to the cutting tools. I propose to
form these cutters of chilled cast iron or steel, or of any other suitably
prepared hardened iron or metal or alloy. They may be cast in cold
iron moulds, and in some cases plunged into iced water for the sudden
abstraction of caloric.
In the tubular drill mortices or seatings are to be formed on the
cutting face and outer periphery for the reception of the stems of the
cutters, the edges of which will then project as may be required for
cutting or boring various descriptions of mineral. They may be made
of any suitable construction useful for cutting or grinding away the
rock or other substance to be operated on.
In some cases I propose to cast a circle of teeth in combination with
a ring to be inserted in a circular seating in the face of the borer.
For a conical pointed borer the cutter is formed with a socket to slip
on the rod of the borer, and for circular or plate or band saws the
cutters may be inserted in the periphery of the former, and between the
plates of the latter, and fixed in any suitable manner.
For cutting coal a series of drills may be used at the same time or the
SPECIFICATION in pursuance of the conditions of the Letters Patent, 20
filed by the said John Macintosh in the Great Seal Patent Office on
the 14th November 1874.
.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MACINTOSH, of the Strand, in the County of Middlesex, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 25
Letters Patent, bearing date the Fourteenth day of May, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Macintosh, Her special license
that I, the said John Macintosh, my exécutors, administrators, and 30
assigns, or such others as I, the said John Macintosh, my executors,

page_text: administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
BORING AND SAWING ROCKS AND OTHER MINERAL SUBSTANCES, AND DRESSING STONE,"
upon the condition (amongst others) that I, the said John Macintosh,
my executors or administrators, by an instrument in writing under my;
or their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately;
after the date of the said Letters Patent.
"
!!
· NOW KNOW YE, that I, the said John Macintosh, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
This Invention consists in the application of chilled or other hard
metal cutting nibs or points to the boring or drilling tools used for
boring rocks, such cutting pieces being applied also to saws and dressing'
tools for stone, the object being to substitute these cutters for the
diamonds at present in use as applied to the cutting tools. I propose to
form these cutters of chilled cast iron or steel, or of any other suitably.
prepared hardened iron or metal or alloy. They may be cast in cold
iron moulds, and, in some cases, plunged into iced water for the sudden
abstraction of caloric.
In the tubular drill mortices or seatings are to be formed on-the
cutting face and outer periphery for the reception of the stems of the
cutters, the edges of which will then project as may be required for
cutting or boring various descriptions of mineral. They may be made
of any suitable construction useful for cutting or grinding away the rock
or other substance to be operated on.
In some cases I propose to cast a circle of teeth in combination with
a ring to be inserted in a circular seating in the face of the borer.
For a conical pointed borer. the cutter is formed with a socket to slip.
on the rod of the borer, and for circular or plate or band saws, the

page_text: +
cutters may be inserted in the periphery of the former and between tho
plates of the latter, and fixed in any suitable. manner.
For cutting coal a series of drills may be used, at the same time, or
the circular or band saw.
The novelty and value of this Invention depends upon the two facts,-
that small portions only of fused or highly heated metal can bo
instantaneously and entirely deprived of their caloric; and that the
colder the medium they are chilled in the harder they become. Acting
on this knowledge I have succeeded in producing small nibs or cutters
of such exceeding density and hardness that they not only cut glass but
also the diamond, to supersede the use of which for boring rocks,
sawing, dressing stone, holeing, sawing, and cutting coal are the chief-
objects of my Invention: In making these nibs or cutters the method
I usually pursue is to drop or place a small quantity of fused or nearly
fused metal (principally iron) into moulds composed of iron or other
suitable material placed in a frigorific mixture of iced water, or in any.
of the well-known freezing.compounds which produce extreme cold,
according to the required degree of hardness and of the shape that may
be required.
In some cases the teeth of saws or the cutting surfaces employed
for the above purposes may be brought to a high temperature short of
fusion and then chilled as above described.
The method of applying the chilled nibs or points to boring, sawing,.
or cutting tools may be greatly varied without departing from the
nature of my Invention, and is so simple that any ordinary workman or
mechanic employed in constructing machines for boring, sawing, cutting,
or grinding minerals or other hard substances will readily understand
how to apply such nibs or points, therefore it is unnecessary to illustrate
the same by Drawings.
Having now set forth the nature of my Invention and the manner of
carrying the same into practice, what I claim is,-
First. The application of chilled or other hard metal cutting nibs or
points in place of diamonds to the boring, sawing, drilling, or cutting
tools used for boring, sawing, and cutting of rocks, coal, and other

page_text: mineral substances, and for dressing stone, substantially in the manner
and for the purposes herein-before described.
Secondly. I claim the improvements in boring and sawing rocks
and other mineral substances, and in dressing stone, substantially as
herein-before described.
In witness whereof, I, the said John Macintosh, have hereunto
set my hand and seal, this Fourteenth day of November, in
the year of our Lord One thousand eight hundred and seventy-
four.
Witness,
J. G. TONGUE,
Patent Agent,
JOHN MACINTOSH. (L.S.)
34, Southampton Buildings,
Chancery Lane,
W.C.