Improved Levelling Instrument, particularly applicable for Photographic Cameras.
Year: 1890

page_text: Date of Application, 27th Jan., 1890
Complete Specification Left, 1st Aug., 1890-Accepted, 24th Jan., 1891
PROVISIONAL SPECIFICATION.
Improved Levelling Instrument, particularly applicable for
Photographic Cameras.
I GEORGE JAMES HEATON of 2 Coburg Villas Albert Road, Old Windsor in the
County of Berks Photographic Artist do hereby declare the nature of this invention
to be as follows:-
-
The object of this invention is to produce a levelling instrument which shall shew
at a glance whether or no the surface to which it is applied is level in every direction,
such instrument being specially suitable for testing the verticality of the "swing
back" in photographic cameras, the said instrument being attached to the camera or
otherwise. According to this invention I take a metal pillar preferably square in
section having each face thereof accurately perpendicular to the adjacent faces and
its ends accurately parallel to each other and at right angles to the sides of the
pillar.
I next bore a hole longitudinally through the centre of the pillar which hole is of
two different diameters. In the lower fourth part or thereabouts of the length of
the pillar the hole is about one eighth of an inch in diameter and the remaining
three fourths of the length of the pillar has the hole through it about three eighths
of an inch diameter.
In the larger hole I insert a piece of glass tubing in the centre of which is
suspended by a few fibres of silk or other suitable material, a small rod preferably
of metal and about one eighth in diameter having the lower end thereof cut off at
right angles to the length of the rod.
I also firmly fix in the smaller hole concentric with the glass tube a similar rod
cut off at right angles to the length thereof, the upper face of which is just clear of
the lower face of the suspended rod.
The metal pillar is cut away except just at the corners, for about three quarters of
an inch so as to form sight holes, the contiguous faces of the two rods coming in the
centre of the "sight." On setting the instrument on a flat surface, if the surface
is level, the two rods will appear as one, but if the surface is not level the upper
rod will project beyond the lower one on that side of the surface which is below the
horizontal. Similarly if the instrument is held vertically against an upright surface,
say the focussing screen of a camera the position of the rods will indicate if the
surface against which it is placed is vertical.
Although I have specified the use of two parallel rods I do not bind myself to
these as I may use two rods with their contiguous ends pointed or other equivalent
means, such as two cups with their mouths nearly touching each other the lower
cup being fixed and the upper one suspended.
Dated this Twenty-fourth day of January 1890
COMPLETE SPECIFICATION.
Improved Levelling Instrument, particularly applicable for
Photographic Cameras.
I, GEORGE JAMES HEATON of 2 Coburg Villas, Albert Road, Windsor, in the
County of Berks, Photographic Artist, 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 this invention is to produce a levelling instrument which shall shew
at a glance whether or no the surface to which it is applied is level in every direction

page_text: such instrument being specially suitable for testing the verticality of the "swing
back" in photographic cameras the said instrument being attached to the camera or
otherwise. According to this invention I take a metal pillar preferably square in
section having each face thereof accurately perpendicular to the adjacent faces and
its ends accurately parallel to each other and at right angles to the sides of the
pillars. I next bore a hole longitudinally through the centre of the pillar which hole
is of two different diameters in the lower fourth part or thereabouts of the length
of the pillar the hole is about one-eighth of an inch in diameter and the remaining
three-fourths of the length of the pillar has the hole through it about three-eighths
of an inch diameter.
In the larger hole I insert a piece of glass tubing in the centre of which is
suspended by a few fibres of silk or other suitable material a small rod preferably
of metal and about one-eighth in diameter having the lower end thereof cut off at
right angles to the length of the rod. I also firmly fix in the smaller hole concentric
with the glass tube a similar rod cut off at right angles to the length thereof, the
upper face of which is just clear of the lower face of the suspended rod.
The metal pillar is cut away except just at the corners for about three-quarters of
an inch so as to form sight holes the contiguous faces of the two rods coming in the
centre of the "sight." On setting the instrument on a flat surface if the surface is
level the two rods will appear as one, but if the surface is not level the upper rod
will project beyond the lower one on that side of the surface which is below the
horizontal. Similarly if the instrument is held vertically against an upright surface,
say the focussing screen of a camera the position of the rods will indicate if the
surface against which it is placed is vertical.
Although I have specified the use of two parallel rods I do not bind myself to
these as I may use two rods with their contiguous ends pointed or other equivalent
means such as two caps with their mouths nearly touching each other the lower cap
being fixed and the upper one suspended.
And in order that my said invention may be the better understood I will proceed
to explain the same with reference to the accompanying sheet of drawings on which
Fig. 1 represents front view of a levelling instrument suitable for attaching to
photographic cameras constructed according to this invention.
Fig. 2 side view and Fig. 3 section of saine.
Fig. 4 front view of a levelling instrument for general purposes also constructed
according to this invention and
Fig. 5 side view of same.
The same letters denote the same parts in all the figures.
a is glass tube suspended rod c fixed rod dd caps of metal or other suitable
material firmly attached to the rigid back e. ff are holes for attaching level to
camera. In Figures 4 and 5 g is a square metal pillar band e suspended and fixed
rods respectively e sight hole h foot to enable the level to be used for levelling a
horizontal surface the back i being used for levelling vertical surfaces j silk fibres.
Instead of silk fibres I may use a very fine metal hook taking into an eye in the
suspended rod.
Having now particularly described and ascertained the nature of my said inven-
tion I declare that what 1 claim is,
The improved levelling apparatus substantially as described and shewn.
Dated this First day of August 1890
G. J. HEATON.