An Improved Plumbing and Levelling Instrument, applicable also as a Clinometer.
Year: 1893

page_text: COMPLETE SPECIFICATION.
An Improved Plumbing and Levelling Instrument, applicable also as
a Clinometer.
A communication from WILLIAM NISBETT, of 192, Shaw Street, in the City of
Toronto, County of York, Province of Ontario, Canada, Carpenter.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
The object of the invention is to produce a sensitive builders level without using
mercury, spirits or any other liquid, and it consists essentially of a disc journalled
in a block with a flat surface the said disc having a pointer or pointers pro-
jecting from its periphery, one side of it being weighted so that the pointer or
pointers shall be held in a vertical position; substantially as hereinafter more
particularly explained.
Fig. 1 is a perspective view of a level partially broken away to show the
invention.
A, represents a plain block made similar to the block used on all spirit levels.
B, is a disc fixed to the spindle C which is journalled in the hangers D projecting
from the plate E.
Instead of fixing the disc B to the spindle C the same effect will be produced by
journalling the disc itself.
F, is a pointer projecting from the periphery of the disc B. It is preferred to
use two pointers F as indicated as it will be easier to see whether the pointers are
perpendicular by glancing at them and the line G and thus observe whether the
surface on which the block A is placed is level. By marking the line G on the
glass H the angle at which the surface lies may be indicated by marking the different
angles on the said glass.
In the drawing is shown two discs B close to the glass H, on each side of the
block, but of course one disc might answer the purpose.
It will be observed that the lower half a of the disc is weighted or made thicker
and thus heavier than the other half, consequently the half a of the disc B will
always be on the opposite side and the pointer F can always be depended upon to
point exactly perpendicular.
By having the line I exactly at right angles to the line G, the improved level
may be used as a plumb, the pointer F then working in connection with the
said line.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondent and in what manner the
same is to be performed I declare that what I claim is ;-
1. A pointer suitably journalled in a block and weighted so that it shall always
remain in a perpendicular position in combination with a line formed on the block
or glass attached thereto substantially as and for the purpose specified.
2. A disc journalled in a block with a flat surface the said disc having a pointer
or pointers projecting from its periphery one side of which being weighted so that
the pointer or pointers shall be held in a vertical position substantially as and for
the purpose specified.
3. A disc B pivotted on the spindle C located within the block A the pointer F
projecting from the periphery of the disc B and a weight a formed on one side of

page_text: the said disc in combination with a glass H having lines G and I made across
its surface and at right angles to each other substantially as and for the purpose
specified.
This 10th of T... 1002
W. P. THOMPSON & BOULT,
Agents for the Applicant.