A NEW OR IMPROVED MANUFACTURE OF IRON FOR TRAMWAY WHEELS OR TYRES
Year: 1872

page_text: LETTERS PATENT to George James Cross, of New Cross, in the County
of Kent, Engineer and Founder, for the Invention of "A NEW OR
IMPROVED MANUFACTURE OF IRON FOR TRAMWAY WHEELS OR TYRES."
Sealed the 30th July 1872, and dated the 2nd February 1872.
PROVISIONAL SPECIFICATION left by the said George James Cross at
the Office of the Commissioners of Patents, with his Petition, on
the 2nd February 1872.
I, GEORGE JAMES CROSS, of New Cross, in the County of Kent,
Engineer and Founder, do hereby declare the nature of the said Invention
for "A NEW OR IMPROVED MANUFACTURE OF IRON FOR TRAMWAY WHEELS OR
TYRES," to be as follows:-
The object of my Invention is to utilize certain irons which have not
heretofore been suitable for the manufacture of tramway wheels or tyres
alone, owing to the difficulty of obtaining the necessary chill and the
liability of the wheels or tyres to crack or split, particularly in the

page_text: winter, when made of the ordinary Scotch or English irons; but by my
Invention I manufacture wheels or tyres for tramways on ordinary roads
above ground, or below ground in mines and pits, from known materials,
by using and combining them in a judicious and particular manner, as
hereafter described, and in this way I am enabled to materially reduce
the cost of manufacture, and at the same time to make use of materials
that are comparatively cheap as compared with the best Swedish or
American pig irons which have been heretofore considered indispensable
for the purpose.
According to my Invention, and in order to make one tramway wheel,
I take 168 pounds of hard white pig metal iron, known as Thornaby and
Linthorpe white pig metal from Middlesbro', or other hard white metal
possessing similar qualities, and 112 pounds of soft pig iron, known as
Calder No. 1 soft pig iron, or soft scrap cast iron, or other soft pig iron
in or about the same quantity as the Calder pig, and possessing similar
qualities to Calder No. 1; these are smelted together, well mixed, and
then run into an ordinary chill box.
.I have found by experiment that the above proportions cannot
with advantage be materially varied to any, very. great extent; for
example, I have found the mixture to be useless for the manufacture of
tramway wheels or tyres if I rise or fall 10 pounds beyond the propor-
tions above given of either the hard or soft pig metal before mentioned,
for by increasing the quantity of soft iron I lose the "chill," and when
I exceed the quantity as aforesaid in hard white pig iron the wheel splits
or cracks.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George James Cross in the Great Seal Patent
Office on the 2nd August 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
JAMES CROSS, of New Cross, in the County of Kent, Engineer and
Founder, send greeting.
i
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of February, in the

page_text: year of our Lord One thousand eight hundred and seventy-two, in
the thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said George James Cross, Her
special licence that I, the said George James Cross, my executors, admi-
5 nistrators, and assigns, or such others as I, the said George James Cross,
my executors, 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
" A NEW OR
IMPROVED MANUFACTURE OF IRON FOR TRAMWAY WHEELS OR TYRES," upon the
condition (amongst others) that I, the said George James Cross, 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 George James Cross, do hereby declare
the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings,, that is to say :—
The object of my Invention is to utilize certain irons which have not
heretofore been suitable for the manufacture of tramway wheels or tyres
alone, owing to the difficulty of obtaining the necessary chill and the
liability of the wheels or tyres to crack or split, particularly in the winter,
when made of the ordinary Scotch or English irons; but by my Invention
I manufacture wheels or tyres for tramways on ordinary roads above
ground, or below ground in mines and pits, from known materials, by
using and combining them in a judicious and particular manner, as here-
after described, and in this way I am enabled to materially reduce the
cost of manufacture, and at the same time to make use of materials that
are comparatively cheap as compared with the best Swedish or American
pig irons, which have been heretofore considered indispensable for the
purpose.
'

page_text: I
weighing say nearly two cwts., of the dimensions shewn at Figure 1 and
Figure 2, which are respectively end view and cross section drawn one-
fourth of the natural size, I take 168 pounds of hard white pig metal
iron, known as Thornaby and Linthorpe white pig metal from Middlesbro',
or other hard white pig metal possessing similar qualities, and 112 |
pounds of soft pig iron, known as Calder No. 1 soft pig iron, or soft
scrap cast iron, or other soft pig iron in or about the same quantity as
the Calder pig, possessing similar qualities to Calder No. 1; these are
smelted together, well mixed, and then run into an ordinary chill
box.
I have found by experiment that the above proportions cannot with
advantage be varied to any very great extent; for example, I have
found the mixture to be useless for the manufacture of such tramway
wheels or tyres if I rise or fall 10 pounds beyond the proportions above
given of either the hard or soft pig metal, for by increasing the quantity
of soft iron I lose the " chill," and when I exceed the quantity as
aforesaid in hard white pig iron the wheel splits or cracks.
Figure 3 is an end view, and Figure 4 a cross section of a tram wheel
of different proportions to the one just described, and weighing say one
and a half cwts. only.
I find that the following would be the proper mixture in order to pro-
duce the results before named with reference to Figs. 1 and 2, as
desirable, viz. -140 pounds of hard white pig metal iron, known as
Thornaby and Linthorpe white pig metal from Middlesborough, or other
hard white pig metal possessing similar qualities, and 140 pounds of soft
pig iron, known as Calder No. 1 soft pig iron, or soft scrap cast iron, or
other soft pig iron possessing similar qualities as Calder No. 1. These
are smelted together, well mixed, and then run into an ordinary chill
box.
From the foregoing it will be seen that the pattern of the wheel and
the substance or thickness of the various parts of the same very
materially affect the quantity of each metal, but that at the same time
the mixture for each particular pattern of wheel is confined within very
narrow limits.
And having thus fully described the nature of this my Invention, and
the mode of carrying the same into effect. I declare that I claim. casting

page_text: tramway wheels of mixtures of soft and hard Scotch or English irons
possessing the qualities herein described, all substantially as and for the
purposes set forth.
In witness whereof, I, the said George James Cross, have here-
unto set my hand and seal, this First day of August, in the
year of our Lord One thousand eight hundred and seventy-
two.
GEORGE JAMES CROSS. (L.S.)