Improvements in Circular Levels.
Year: 1894

page_text: Date of Application, 10th Mar., 1894
Complete Specification Left, 7th Dec., 1894-Accepted, 23rd Feb., 1895
PROVISIONAL SPECIFICATION.
Improvements in Circular Levels.
I, JAMES JOSEPH HICKS of 8 Hatton Garden, in the County of London,
Meteorological Instrument Manufacturer, do hereby declare the nature of this
invention to be as follows:-
"
The invention relates to that class of level known as the "circular level and
consists of a novel construction thereof whereby leakage is prevented and the level
thereby rendered permanently effective so long as it remains unbroken.
Heretofore such class of level has been made with a cylindrical metal body into
the upper part of which a glass face has been cemented, a small hole being left in
the body through which it is supplied with the required quantity of liquid to leave
a small air bubble after which said hole is closed; this construction has always been
liable to leak thereby rendering the level useless after a longer or shorter period
of time.
According to my present invention I construct a circular level as follows:-
I blow a glass chamber with a flat face, or it may be with a lens shaped face, and
with a small tube or splint through which the level is supplied with fluid, I then
seal the tube or splint by means of a blow pipe and afterwards mount the said glass
level in any suitable frame or holder.
Dated March 10th 1004
Improvements in Circular Levels.
1, JAMES JOSEPH HICKS, of 8 Hatton Garden in the County of London,
Meteorological Instrument Maker, 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 invention relates to that class of level known as the "circular level," and
consists of a novel construction thereof whereby leakage is prevented and the level
thereby rendered permanently effective so long as it remains unbroken.
Heretofore such class of level has been made with a cylindrical metal body, into
the upper part of which a glass face has been cemented, a small hole being left in
the body through which it is supplied with the required quantity of liquid to leave
a small air bubble after which said hole is closed. This construction has always
been liable to leak, thereby rendering the level useless after a longer or shorter
period of time.
According to my present invention I remedy this inconvenience by constructing
the body of the level entirely of glass, supplying the same with liquid, and sealing
the same by means of the blow pipe.

page_text: I will now describe, referring to the accompanying drawings, the preferred
methods in which I carry my invention into effect.
Figures 1, 2, 3, 4, represent in section the various stages of blowing a piece of
glass tube to form a high quality of my improved level.
Figures 5 and 6 are sertions of completed levels without their mounts and
Figure 7 is a section of a level in a suitable mount.
Figure 8 represents a side or edge view and Figure 9 a plan of a cheaper and
smaller level.
Figure 10 represents a side view and Figure 11 a plan of a slightly modified
form of my improved level.
Figures 12 to 17 represent various processes of treating a tube or cane of glass
in the production of the levels shown at Figures 8, 9, 10 and 11.
. I will first describe the preferred mode of constructing levels such as those
shown at Figures 5, 6, 7.
I take a glass tube a and, by means of a blow pipe, I melt the glass and close one
end a¹ thereof, as shown at Figure 1. I then flatten or nearly flatten the end a' as
shown at Figure 2, after which I blow on to such flattened end a rod of glass a³, as
shown at Figure 3, in order to enable the partly formed level to be manipulated at
a subsequent operation. I then at about the line a Figure 2, cut off sufficient of
the tube a to form the required level chamber, when it will appear as shown at
Figure 3, at which stage it is well annealed. For a high class level I then grind
and polish the inner face of the end a to a true and slightly concave form, during
which operation the partly formed level is held by the rod a³.
I next, by the aid
of the blow pipe, melt and draw down the cylindrical part a to the shape shown
at Figure 4, so as to form a finely perforated nipple a. The glass rod a' is then
cut off and the outer face of the end a' forming the top of the level is ground and
polished.
The glass chamber thus formed is then supplied through the nipple a' with the
required amount of liquid, after which the nipple a is fused and hermetically
sealed by the blow pipe, thereby forming the complete level as shown at
Figure 5.
I sometimes form the level shallower from top to bottom as shown at Figure 6.
If desired the grinding and polishing of the inner face of the end a may be
dispensed with.
A level formed as above described may-be mounted in a chamber b as shown at
Figure 7, the space between it and the bottoin of said chamber being filled with
plaster of Paris or other cement, and an open faced cap being placed over the
level and fitting tightly the exterior of the chamber b.
In constructing a level of the form shown at Figures 8 and 9, I proceed as
follows take a plain tube or cane of glass c and, by the blow pipe, I melt and
close one end c' and draw down a perforated splint c², as shown at Figure 12, I then
again melt and contract the splint as fine and as near as possible to its junction
with the end c', as shown at Figure 13, after which I melt the tube c at the line o³,
see Figure 13, and close it at that part as shown at Figure 14, after which I detach
the partly formed level from the tube c.
The bulb thus formed is again melted and blown out and turned about to
obtain an equal thickness of metal all over the same and to make it of a truly
globular form, when it will appear as shown at Figure 15, after which it is again
melted all over and flattened as shown at Figure 16 between two plane surfaces of
metal, porcelain, or other suitable material. Then, in order to give the level the
slightly curved face required as shown at Figure 17, it is again melted and the
operator breathes gently into the same, after which the unnecessary portion of
the splint is removed; the bulb c is then supplied with liquid through the small
nipple and the latter is sealed by the blow pipe.
In forming a level of the shape shown at Figures 10 and 11 proceed as above
described until the stage represented at Figure 15 is reached, when, instead of
flattening the bulb c on its sides, I flatten it on its end as shown at Figure 16*;

page_text: after which I again melt it and then gently breathe into it to give it a slightly
curved face, as shown at Figure 17^; the excess in length of the splint c
removed and the level finished as before described.
then
A level such as shown at Figures 8 and 9 or 10 and 11 can be provided with any
suitable mouut.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A circular glass level constructed by blowing a tube or cane of glass to the
required form of bulb or chamber provided with a finely perforated nipple,
furnishing said chamber with the requisite quantity of liquid, and subsequently
hermetically sealing the nipple by means of fusion, substantially as herein shown
and described.
2. A circular glass level constructed by blowing a tube or cane of glass to a cup
form, fusing to the bottom of the cup a manipulating rod or handle of glass, fusing
and drawing down the open end of the cup to form a chamber with a finely
perforated nipple, removing the said rod or handle, polishing the top of said
chamber, supplying said chamber through the nipple with the requisite quantity of
liquid, and finally fusing the nipple to hermetically seal the same, substantially as
herein shown and described.
3. A circular glass level constructed by blowing a tube or cane of glass to a cup
form, fusing to the bottom of the cup a manipulating rod or handle of glass, grinding
and polishing the inner face of the bottom of said cup, fusing and drawing down the
open end of the cup to form a chamber with a finely perforated nipple, removing
the said rod or handle, polishing the top of said chamber, supplying said chamber
with the requisite quantity of liquid, and finally fusing the nipple to hermetically
seal the same, substantially as herein shown and described.
Dated December 7th 1894.
Dated December 7th 1894.
J. J. HICKS,
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.