AN IMPROVED TABLET FOR SHARPENING OF RAZORS, PENENIVES, SURGICAL INSTRUMENTS, CHISELS, PLANE IRONS, AND OTHER STEEL INSTRUMENTS WHICH ARE CAPABLE OF BEING SHARPENED BY WHAT ARE COMMONLY CALLED HONES, TURKEY STONES, AND WELCH STONES
Year: 1836

page_text: HIGHAM'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WARD HIGHAM, of Tavistock Street, in the Parish of Saint Giles in the Fields,
in the County of Middlesex, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eleventh day of January, in the sixth year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said John
Ward Higham, His especial licence, full power, sole privilege and authority,
that I, the said John Ward Higham, my exors, adñiors, and assigns, or such
others as I, the said John Ward Higham, my exors, admors, and assigns,
should at any time agree with, and no others, from time to time and at all
times during the terms of years therein mentioned, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of
Berwick-upon-Tweed, my Invention of "AN IMPROVED TABLET FOR SHARPENING
OF RAZORS, PENENIVES, SURGICAL INSTRUMENTS, CHISELS, PLANE IRONS, AND OTHER
STEEL INSTRUMENTS WHICH ARE CAPABLE OF BEING SHARPENED BY WHAT ARE
COMMONLY CALLED HONES, TURKEY STONES, AND WELCH STONES;" in which said
Letters Patent is contained a proviso, that I, the said John Ward Higham,
shall cause a particular description of the nature of my said Invention, and in
what manner, the same is to be performed, by an instrument in writing under
my hand and seal, to be inrolled in His said Majesty's High Court of Chan-
cery within two calendar months next and immediately after the date of the

page_text: said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Ward Higham, do hereby declare that the nature of my said Invention
and the manner in which the same is to be performed, are particularly
described and ascertained in and by the following description thereof, reference
being had to the Drawings hereunto annexed (that is to say):-
My Invention consists of improved tablets for sharpening of razors, pen-
knives, surgical instruments, chisels, plane irons, and other steel instruments
which are capable of being sharpened by what are commonly called hones,
Turkey stones, and Welch stones.
I now hereby describe the different processes of manufacturing them.
Figure 1 represents the face of one of my improved tablets; Figure 2
being an edge view of it. It consists of a slip or flat piece of plate glass of
about eight and a half inches long, one inch and a half wide, and an eighth of
an inch thick, more or less, or of any other convenient sizes or thicknesses,
shape, or form, and according to the use it is to be applied to; or I take
instead thereof double stout crown glass, of about the same size and thickness,
or I can employ crown glass of a lesser thickness; and for the sake of strength
I combine two slips or pieces together by means of cement, in the manner to
be described hereafter. This crown glass should be as even in its thickness
and as flat as can be conveniently obtained. If the edges are not cut true
and straight it will be necessary to use a fine flat stone, which may or may not
be attached to a wheel, and by the use of the said stone, aided by water and
emery or fine sand, I grind the said edges true in shape, by applying them to
the face of the stone, after which I use the same stone alone, and water
without the emery or sand, to grind and bevel the upper edge of the slip quite
smooth, or to a polish, and so thatno notches or inequalities remain on the
bevel edge. I next grind or roughen the surface of the tablet on the same side
as the edges have been bevelled. I procure for this purpose the best emery,
letting the same bo well ground and levigated, and then well washed over, the
same being applied with water and a glass mullar by moving the mullar about,
with but little pressure in all directions on the glass; the tablet being pre-
viously firmly imbedded upon any proper flat surface, as a table or work bench,
or a marble or stone slab, for instance, by means of plaster of Paris mixed with
water to a due consistence, as usual. The grinding must be carefully per-
formed, and be continued until the surface, or that part of it which you may
think proper to grind, is of a uniform gray appearance. The glasses being

page_text: then unmounted, is next to be coated or painted over with an enamel, the
composition of which will be described hereafter, and afterwards vitrified in an
enameller's surface under a muffle. In preparing the enamel, I take one part
by weight of the red oxide of the lead and two parts of flint glass for a flux,
let these be fused together in a crucible, and when sufficiently melted be
poured out into cold water; when dry, let it be pulverized and sifted and
ground. Then take the following brown oxide of iron, prepared by calcining
sulphate of iron in a crucible, and submitting it to a bright red heat till burnt to
a dark reddish brown; let it then be well and frequently washed in hot water,
and then well ground in cold water; when dry add one part by weight of the
prepared Bux to an equal weight of the calcined oxide of iron, mix these ingre-
dients well together, and repeat the grinding with the essential oil of turpentine,
adding also a little oil of spike lavender, till ground very fine, then paint or
coat the glasses with this enamel; when well dried the glasses must be sub-
mitted to a slight red heat in a fire made with coke or charcoal, when placed
in the enameller's furnace for vitrification, first, however, laying them upon an
even surface of whiting or finely washed chalk spread upon an iron plate;
when they are vitrified enough, but still having a matted surface, or being
prevented from flowing smooth, they must be suffered to remain in the muffle,
or in an annealling surface, and be slowly cooled therein, for the purpose of
annealling them. The enamelled faces of the glasses must then be ground
and finished with the emery and water, before described, and a glass muller to
an uniform even surface, and which is indispensibly necessary. The plate
glass will generally be thick enough in its own substance, but the crown glass
will need to be strengthened by being cemented to another piece of crown
glass by means of a cement composed of two parts of hard tallow, one part of
black resin, and one part, more or less, of beeswax, melt it together and
applied to the glasses when they are properly heated These glass tablets,
shown in front and edgeways in Figures 1 and 2, for their further support are
also to be mounted upon thin wooden slips, of a convenient size or shape, with
a similar cement, and they are also to be veneered around their edges with
slips of ivory, tortoise-shell, ebony, or any other wood, or be. covered with
leather, cloth, or paper. They will now be in a fit state to receive a composi
tion formed of two parts by weight of the oxide of tin, and one part of finely
ground flint glass, to which is added one part of the reddish brown oxide of
iron, all to be finely ground together, with a mixture of olive oil and hogs lard,
to the consistence of an unguent; when used it must be uniformly spread, cither
with a cork or a leather rubber, or the finger, uniformly over the surface of the
-

page_text: glass tablets, they will then be in a fit state for giving a very superior and
keen edge to razors, penknives, and surgical instruments, by using the tablets
for sharpening tho different instruments in a similar way as is generally done
by making use of the houe for that purpose. For giving a fine edge to chisels
and plane irons, and other steel instruments capable of being sharpened by the
bone, Turkey stone, or Welch stone, Figures 3 and 4, used by carpenters,
joiners, and cabinet makers, I use the same means as before stated, excepting
that in the composition or unguent I add one part of the before-mentioned
prepared emery; and the tablets may be made to any size, form, shape, or
thickness suitable to their intended purposes. They are to be applied in the
same way as is generally done on a hone, Turkey stone, or Welch stone.
I have thus described what I believe to be the best mode of forming my
tablets. The composition to be laid on the surface of the tablets, as before
described, may be conveniently held in a small bottle, Figure 5, furnished with
a cork, having a wire fixed in it, to take up a small quantity of the said compo-
sition. I can also apply my said compositions in the consistence of unguents
upon greyed or finely-ground glass, without enamelling, but not with so good
an effect as when it has been enamelled in order to give fine edges to razors,
penknives, surgical instruments, chisels, and plane irons.
I do not mean or intend hereby to claim as my Invention any of the various
methods which may have already been known and in use, nor the materials
employed; but only my improved methods of using them in combination for
the purposes herein-before described, and particularly the application of my
enamel upon a ground or greyed surface of glass, and the carrying the
enamelling process only so far as to fix the enamel thereon firmly, but to leave
it with a matted surface, instead of a smooth or polished surface as usual; also
the grinding of the said enamelled surface flat or even after the enamelling
has been performed; and also the application of my said unguents upon the
caid enamelled surfaces, or upon the greyed or finely-ground glass, without
enamelling it, in order to afford fine edges to razors, penknives, surgical
instruments, chisels, plane irons, and other steel instruments which are capable:
of being sharpened by what are commonly called hones, Turkey stones, or.
Welch stones.
In witness whereof, I, the said John Ward Higham, have hereunto set
my hand and seal, this Tenth day of March, in the year of our
Lord One thousand eight hundred and thirty-six
JOHN WARD (L.s.) HIGHAM.

page_text: AND BE IT REMEMBERED, that on the Tenth day of March, in the
year of our Lord 1886, the aforesaid John Ward Higham came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Tenth day of March, in the year of our Lord One thousand
eight hundred and thirty-six.