Year: 1886

page_text: I, WILLIAM WILSON HULSE of the Ordsal Tool Works, Salford, in the County
of Lancaster, Engineer, 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:-
These improvements relate to Spirit Levels for use in the manufacture and
erection of machinery and other constructional work. The spirit levels are made
so as to be as applicable for testing vertical lines and surfaces as for testing
horizontal ones, without the intervention of squares or other separate appliances;
and provision is made for readily ascertaining the extent of small deviations from
vertical and horizontal positions. In the accompanying drawings Figs. A, B, C, D
illustrate one modification of the present improvements; Figs. A and B are both
side elevations; the former shews the spirit level 1 applied to a vertical object 2,
and the latter shews it applied to a horizontal object 3; Fig. C is an end elevation
projected from Fig. B, and Fig. D a plan projected from Fig. A. It will be seen
that in this arrangement the spirit level has two limbs standing at right angles to
each other, one vertical and the other horizontal. The bubble tube 4 is situated in
the horizontal limb and is graduated with divisions such that each one corresponds
with a prearranged unit of inclination as for example, the one thousandth part of
an inch per foot of length. The vertical limb is shewn with a groove formed in it
for facilitating the application of the Spirit Level to vertical round shafts and the
like. The horizontal limb may also have a groove formed in it. Other devices
equivalent to the groove may be adopted in some cases. Fig. E is a side elevation,
and Fig. F an end elevation of another modification of the present improvements.
In this case the level is formed as a rectangular frame, presenting two horizontal
and two vertical surfaces for application to the work. The bubble tube 4 is shewn
situated in the upper horizontal bar of the frame; other arrangements of the
bubble tube may however be adopted according to circumstances.
For example it may be fixed in the lower bar of the frame so as to be convenient
for testing the underside of horizontal objects, or there may be a bubble tube in
each horizontal bar, or there may be two bubble tubes fixed in one of the horizontal
bars, (one at the top and the other at the bottom side) in such a manner that
observations can be taken whether the level is turned one way up or the other.
This modification is also applicable to the arrangement shewn in Figs. A, B, C, D.

page_text: Sometimes instead of having two bubble tubes in one bar, a single bubble tube
may be employed so formed as to give correct readings whether the level is placed
one way up or the other. When desired the bubble tubes may be made adjustable
by setting screws as is usual. In some cases the Spirit, instead of being contained
in one or more glass tubes, may be placed in a chamber (made in the level) covered
in at the top and bottom with glass, carefully formed on the inside, with the degree
of curvature required for the proper action of the bubble. The bubble will float
against one or other of the glass covers (both of which are graduated with
divisions as described for the tubes,) according as the level is placed one way up
or the other.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. A spirit level constructed substantially as shewn in Figs. A, B, C, D, and
W. LLOYD WISE,
Agent for the Applicant.