A NEW METHOD, DIRECTED BY MACHINERY, OF USING THE SCREW, BY WHICH ITS MECHANICAL POWER OR ITS MOTION IS ENCREASED
Year: 1809

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
STEERS, of the Inner Temple, London, Esquire, send greeting.
WHEREAS His present Majesty King George the Third, in and by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the First day of March instant, for Himself, His heirs and successors,
did give and grant unto me, the said Edward Steers, His especial licence, full
power, sole privilege and authority, that I, the said Edward Steers, my execu-
tors, administrators, and assigns, and every of them, by myself and themselves,
or by my or their deputy or deputies, servants or agents, or such others as I,
the said Edward Steers, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and at all times thereafter
during the term of years therein expressed, should and lawfully might make,
use, exercise, and vend, within England, Wales, and the the Town of Berwick-
upon-Tweed, my Invention of "A NEW METHOD, DIRECTED BY MACHINERY, OF
USING THE SCREW, BY WHICH ITS MECHANICAL POWER OR ITS MOTION IS ENCREASED;"
in which said Letters Patent there is contained a proviso obliging me, the said
Edward Steers, by an instrument in writing under my hand and seal, particu-
larly to describe and ascertain the nature of my said Invention, and in what
manner the same is to be performed, and to cause the same to be inrolled in
His Majesty's High Court of Chancery within one calendar month next and
immediately after the date of the said recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully appear.

page_text: NOW KNOW YE, that in complianco with the said proviso, I, the said
Edward Steers, do hereby declare the following to be a description of my
Invention of a new method, directed by machinery, of using the screw, viz:-
The new method of applying the mechanical power of the screw is, in the
first place, by the screw and nut being made to revolve together either in the
same or in a contrary direction. If they turn in the same direction, the one
somewhat faster than the other, an increase of power is obtained; if in a con-
trary direction, there is an increase of motion produced. In the second place,
the new method is by two screws placed opposite to each other, revolving
together in the same circular direction or in a contrary direction, their nuts
being fixed; or, in the third place, by their nuts revolving together, the screws
being fixed. The machinery necessary to direct the operation of this new
method must be such as will turn the screw and nut, or the two screws or
their nuts, one quicker than the other, in the same direction, or such as will
turn them in a contrary direction. There are various modes of producing
these effects, which an ordinary knowledge of mechanics will suggest. One
mode the following description and the annexed Drawing will explain :-
:-
The wheels A and B fixed upon the nut A and screw B (see Figures 1 and
2, are of the same diameter, but the wheel A has one tooth more than the
wheel B; they are turned by the same pinion C. Now suppose the wheel A
to have one hundred and one teeth, and the wheel B one hundred teeth, then
when the wheel A has made one revolution, the wheel B will have made
one revolution and the one hundredth part of another; consequently the
screw will have risen one hundredth part of the distance between two of its
threads, and the increase of power obtained by this new method will be in the
proportion of one hundred to one. Now suppose there be another screw D,
and nut E, revolving round a pin in the centre of the upper part of the screw
B, and suppose to the screw D be fixed a wheel having one hundred and
two teeth, and to the nut E a wheel having one hundred and one teeth, then
when they are turned round by the same pinion, as soon as the screw D has
made one revolution, the nut E will have made one revolution and the one
bundred and first part of another revolution, by which operation the nut
E will be lowered the one hundred and first part of the distance between
two of the threads of the screw. The turning of the two first mentioned
wheels then has the effect of raising the nut E the one hundredth part, and the
turning of the two last-mentioned wheels the effect of lowering the nut E the
one hundred and first part of the distance between two of the threads of the
screw; consequently, when the wheels are turned altogether once round the same
pinion, the effect is that of raising the end F the ten thousand one hundredth

page_text: part of the distance between two of the threads of the screw, and the increase
of power obtained by this new method will be in the proportion of ten thousand
one hundred to one. The two wheels in the small frame G, which is attached
to the large one by hinges, are to be used when it is required to produce an
increase of velocity; for this purpose the pinion C must be raised upon its
axis so as to be disengaged from the wheel A, and the wheels in the small
frame must be brought in contact with the pinion C and wheel A (see Figures
1 and 3), so that the pinion C may turn the upper wheel in the small frame,
and the lower wheel in the small frame turn the wheel A; the effect will be
that of turning the wheels A and B in contrary directions; the screw and
nut will move in opposition to each other, and the end F will rise by this new
method with increased velocity.
Figure represents two screws with their nuts placed opposite to each
other. Now suppose the screws to be turned by machinery similar to that
already described, their nuts being fixed; then if they be turned in the same
circular direction, one screw will advance and the other recede; or if the
screws be fixed and the machinery applied to the nuts, then one nut will
advance and the other recede; but as the motion of one will be quicker than
that of the other, they will gradually approach, and there will be an increase
of power produced, as was explained when the screw and nut were supposed to
revolve together.
In witness whereof, I have hereto set my hand and seal, the Twenty-
ninth day of March, in the year of our Lord One thousand eight
AND BE IT REMEMBERED, that on the same Twenty-ninth day of
March, in the year above mentioned, the aforesaid Edward Steers came
before our Lord the King in His Chancery, and acknowledged the Specifi-
cation aforesaid, and all and every thing therein contained, in form above
Owritten. And also the Specification aforesaid was stamped according to the
tenor of the Statute in that case made and provided.