An Improved Galvanometer-lamp, Stand, and Scale.
Year: 1895

page_text: Date of Application, 8th Jan., 1895
Con:plete Specification Left, 8th Oct., 1895-Accepted, 8th Jan., 1846
PROVISIONAL SPECIFICATION.
An Improved Galvanometer-lamp, Stand, and Scale.
We, HENRY FREDERIC WILLIAM BURSTALL, M.A., of 76 King's Road,
Camden Town, Civil Engineer, and JAMES JOSEPH HICKS, of 8 Hatton Garden,.
Meteorological Instrument Manufacturer, both in the County of London, do
hereby declare the nature of this invention to be as follows:-
The invention has for its object an improved arrangement and combination of
parts forming an improved galvanometer-lamp, stand and scale.
:
We employ a small electric lamp mounted in a telescopic tube provided with a
lens at one end mounted by a ball and socket or other universal joint on the top of
a telescopic upright, so that the lamp body can be adjusted and held at any
desired height and angle. On each side of the said telescopic upright we fix to
the base an upright fitted with a telescopic tube, on the upper ends of which
tubes is fixed or mounted a ground glass or other transparent scale, which latter
we prefer to fit with a rack and pinion to facilitate lateral adjustment thereof.
Dated this 8th day of January 1895.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.
We, HENRY FREDERIC WILLIAM BURSTALL, M.A., of 76 King's Road,.
Camden Town, Civil Engineer, and JAMES JOSEPH HICKS, of 8 Hatton Garden,
Meteorological Instrument Manufacturer, both in the County of London, 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 has for its object an improved arrangement and combination of
parts forming an improved galvanometer-lamp, stand and scale.
We employ a small electric lamp mounted in a telescopic tube provided with a
lens at one end mounted, by a ball and socket or other universal joint, on the top.
of a telescopic upright, so that the lamp body can be adjusted and held at any
desired height and angle. On each side of the said telescopic upright we fix to
the base an upright fitted with a telescopic tube, on the upper ends of which tubes.
is fixed or mounted a ground glass or other transparent scale, which latter we
prefer to fit with a rack and pinion to facilitate lateral adjustment thereof.
In the accompanying drawings Fig. 1 is a front elevation, Fig. 2 a plan, and
Fig. 3 a vertical cross section drawn on the line 3-3 of Fig. 1, showing a combined
galvanometer-lamp, stand and scale constructed according to our invention.
Fig. 4 is an internal view and Fig. 5 is a longitudinal section of the lamp and its.
holder separately.
a, Figs. 4 and 5, is a small electric lamp and fitting mounted in a tube b and
connected with terminals 6' 6', to which the ends of electric conducting wires c care.
D

page_text: connected. A tube 62 provided with a lens at 63, fits telescopically the tube b to
enable the light of the lamp a to be correctly focussed on to the galvanometer
mirror. The tube 6 is mounted, by a ball and socket or other universal joint d, on
the top of a telescopic upright e, which latter is also mounted at its lower end
on a hinge joint e¹ carried by the base f; by these means the telescopic tube
carrying the lamp can be adjusted and held at any desired height and angle.
On each side of the telescopic upright we fix to the base f, preferably by
means of a hinge joint 91, an upright a fitted with a telescopic tube g². On the
upper ends of these tubes 92 is fixed a carrier y³ in which is mounted, with
capability of sliding therein, a ground glass or other transparent scale h, which
latter we prefer to fit with a rack and pinion h³ to facilitate lateral adjustment
thereof.
The lower ends of the wires c c are attached to the terminals i i, to which latter
main electric conducting wires jj are connected.
The lens 63 has a line or fibre across it.
The apparatus is used as follows. The tubes 6 63 carrying the lamp a are so
adjusted as to throw the light and the image or shadow of the line or fibre across
the lens 63 on to the galvanometer mirror, and the scale h is so adjusted that the
image or shadow of the line or fibre thrown thereon by the galvanometer reflector
is coincident with the zero line of the scale; the extent of motion of the
galvanometer mirror is then ascertained by observation of the image or shadow
thereof moving along the scale on either side of the zero point.
We would here remark that the details of construction of the several parts
can be variously modified without departing from the peculiar features of our
invention.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
:-
1. In galvanometer-lamps, stands and scales, the peculiar combination and
arrangement of parts substantially as herein shown and described.
2. In galvanometer-lamps, stands and scales, the combination of a lamp carried
by a telescopic tube provided with a lens and mounted with capability of adjust-
ment as to height and angle on an upright, and a transparent scale mounted
on uprights with capability of adjustment thereon as to height and angle, the
various uprights being mounted on a suitable base, all substantially as herein
.shown and described.
3. In galvanometer lamps, stands and scales, the combination of a lamp
mounted in a telescopic tube provided with a lens, and a line or fibre across the
lens, a transparent scale, means for adjusting said scale endwise, means for
adjusting the heights and angles of the lamp tube and scale, and a base carrying
Baid parts, substantially as herein shown and described.
Dated this 8th day of October 1895.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.