| |
A
is the stock, made of wood or any other suitable material,
in the upper edge of which is secured a spirit-vial in the
ordinary way in making the common level. B is a metallic plate
made in the form of a right angle, intersected at each end
thereof by a circle-plate, B', said circle-plate being struck
from the point b, near the angle of the plate B, the face
of which is divided into fractional parts or degrees up to
a quarter of a circle or a right angle. C is a tube, in which
is secured a spirit-vial. D is a traverse-bar, made in any
proper or desired shape and secured upon and moves on the
pin or screw at a point, 1). Upon the inside of this bar D
is secured the spirit vial or tube C, by means of a fixed
pin or screw, c, at one end, and by an adjustable set-screw,
d, at the other end. E is a bolt, the head of which is fitted
into the slit in the circular plate B', so as to move freely
therein, the screw of which passes through the traverse-bar
D, and receives a thumb-nut, F, the object of which thumb-nut
and bolt is to hold the outer end of the traverse-bar D, through
which it passes, firmly at any fixed point on the circular
plate B'. (T are hubs fixed nearly at the ends of the circular
plate B' so as to allow it (the plate B') to move or traverse
a quarter of a circle as nearly as may be. A depression, H,
is cut in the stock A, of the desired shape to allow of the
traverse of the tube C, and depressions are also cut for the
thickness of the plates B B' to secure more perfectly against
any movement of the device, and the said plates are secured
therein by screws.
Now, when this instrument is made, first place the traverse-bar
down firmly against the hub G-, in a parallel line with the
stock, and then adjust the spirit-vial or bubble in a level
position and secure it by the set-screw d. Then the instrument
is ready to be used for either a plumb or a level, or to be
used at any other angle desired within ninety degrees of a
circle, by simply loosening the thumb- nut F and moving the
traverse-bar to the desired point and again securing it in
that position by the said nut.
I believe I have shown the nature, construction, and operation
of my improvement so as to enable others skilled to make and
use the same.
What I claim, therefore, and desire to secure by Letters
Patent, is—
The employment of the right-angle and circular plates B B',
traverse-bar D, and tube C, in combination with a spirit-level
stock, substantially in the manner as and for the purpose
described.
FREDERICK A. TRAUT
Witnesses:
A. B. GILLETT,
JEREMY W. BLISS.
|
|
