IMPROVEMENTS IN MINING AND OTHER SIMILAR SAFETY LAMPS
Year: 1878

page_text: LETTERS PATENT to George William Smith, of Glasgow, in the County of
Lanark, North Britain, Civil and Mining Engineer, for the Invention of
IMPROVEMENTS IN MINING AND OTHER SIMILAR SAFETY LAMPS."
"
Sealed the 9th August 1878, and dated the 21st February 1878.
PROVISIONAL SPECIFICATION left by the said George William Smith at
the Office of the Commissioners of Patents on the 21st February 1878.
GEORGE WILLIAM SMITH, of Glasgow, in the County of Lanark, North Britain,
Civil and Mining Engineer.
"IMPROVEMENTS IN MINING AND OTHER SIMILAR
SAFETY LAMPS."
This Invention has for its object to construct mining and other similar safety
lamps in a novel and simple manner, and so as to render them less liable than
hitherto to be opened or otherwise tampered with by the miners when in use.
By one modification of the present improvements as applied to a "Davy" or
similar form of lamp, the short metallic cylinder forming the oil chamber at the
bottom of the lamp replaced by a series of rings of channel section lying hori
zontally on each other, and presenting the same outward appearance as the cylinder.
The vessel containing the oil or other hydrocarbon is fitted with a row of projecting
studs corresponding in position and depth to the channels or circular grooves in the
rings, and when the oil vessel is to be inserted into its place within the lamp the
rings are arranged so that notches or indentations cut in their inner peripheries
form a continuous vertical groove, and allows the studs to pass freely up to their
respective channels or circular grooves. By turning the rings and the oil vessel
slightly round the studs pass round into their corresponding circular grooves, and
retain the oil vessel locked to the lamp. Letters or numerals are stamped or marked
at intervals round the outer peripheries of the rings and round the bottom of the
oil vessel, those numerals or letters which occur opposite the notches in the rings
and below the studs on the oil vessel being in a known consecutive order vertically,
and the oil vessel can be withdrawn only when it and the rings are turned to form
the known order of letters or numerals, that is, back to the original position.

page_text: The improvements may be adapted to any kind of cylindrical lamp, and when
preferred a second series of similarly notched and grooved rings may be added on to
the exterior of the first series, and be arranged so that the oil vessel can be withdrawn
on turning it, and the rings to form a certain consecutive order of letters or numerals
determined upon when the vessel is inserted.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George William Smith in the Great Seal Patent Office on the
15th August 1878.
GEORGE WILLIAM SMITH, of Glasgow, in the County of Lanark, North Britain,
Civil and Mining Engineer. "IMPROVEMENTS IN MINING AND OTHER SIMILAR
SAFETY LAMPS."
My said Invention has for its object to construct mining and other similar safety
lamps in a novel and simple manner, and so as to render them less liable than
hitherto to he opened or otherwise tampered with by the miners when in use.
By my improvements, which are applicable to any cylindrical form of lamp, the
short metallic cylinder which usually forms the oil chamber at the bottom of the
lamp is replaced by a series of channeled or grooved rings, and these rings form
with the oil vessel fitting into them a permutation or number lock, from which the
oil vessel can only be withdrawn or unlocked when the rings and the vessel are
turned into positions in which certain letters or numerals marked at intervals round
their peripheries form a predetermined sequence of letters or number.
And in order that my said Invention and the manner of performing the same
may be properly understood I hereunto append a Sheet of explanatory Drawings,
to be herein-after referred to, and representing modifications of my improved safety
lamps.
In these Drawings the same reference numerals are used to mark the same or
like parts wherever they are repeated.
Figures 1 and 2 are elevations, and Figure 3 is a horizontal section of a miner's
safety lamp of the Newcastle pattern, embodying one modification of my improve-
ments.
In this modification the oil chamber at the bottom of the lamp is composed of a
series of rings 6 of channel or L section lying horizontally on each other, and
presenting the same outward appearance as the cylindrical chamber of an ordinary
lamp. These rings 6 are retained in their places vertically by a pair of fixed
rings 7, 8, attached to the lamp body, and are prevented from having lateral play
partly by checks turned or cut in the fixed rings, and partly by wire rods 9, which
hold these rings 7, 8, together. The vessel 10 containing the oil or other hydro-
carbon, and shown in Figure 2 removed from the lamp, is fitted with one or more
rows of projecting studs 11, corresponding in position and depth to channels 12
formed by the rings 6. When the oil vessel 10 is to be inserted into its place

page_text: within the lamp the rings 6 are arranged as shown in Figure 1, so that notches or
indentations 13 cut in their inner peripheries form a continuous vertical groove,
and allow the studs 11 to pass freely up to their respective channels or circular
grooves 12. On turning the rings 6 (or any of them) and the oil vessel 10 slightly
round the studs 11 pass round into their corresponding circular grooves 12, and
retain the oil vessel 10 securely locked to the lamp. Letters, or it might be numerals
or other symbols, are stamped or marked at intervals round the outer periphery of
each ring 6, and round a disc on the bottom of the oil vessel 10, those letters or
numerals which occur opposite the notches 13 in the rings and below the studs on
the oil vessel 10, being in a predetermined consecutive order vertically, and the oil
vessel 10 can be inserted or withdrawn only when it and the rings 6 are turned
or placed so as to form the known order of letters or numerals. In the present
instance the required sequence of letters forms the word PATENT, one of the
letters A, being stamped on the lower fixed ring 8.
Figures 4 and 5 are respectively an elevation and a vertical section of separate
parts of a lamp of the Scotch gauze pattern, showing another modification of my
improvements applied thereto. In this example the oil vessel 10 is held in a
chamber fixed to the lamp, and this chamber is locked by means of studs 11 on it
in the manner explained with reference to Figures 1 and 2 to an outer chamber
(Figure 5) similar to the oil chamber in Figure 1, but with the rings inverted.
In another modification of any improvements a second series of channeled or
grooved and notched rings is added on to the exterior of the first series, and may
be arranged so that the oil vessel can be withdrawn only on turning it and the
rings to form a certain consecutive order of letters or numerals determined upon
when the vessel is inserted. By this arrangement the opening word or number may be
altered from day to day, and the chance of a key word or number for any lamp being
discovered by the workmen will be greatly diminished; but for practical purposes
the combination of letters or numbers formed by the single series of rings are
sufficiently numerous to prevent any successful attempt at unlocking the lamps.
Having thus particularly described my said Invention, and the manner in which
the same is performed, I have to state that I do not restrict myself to the precise
details herein-before described or delineated, but that what I believe to be novel
and original, and claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
1. The arrangement and combination of parts forming a safety lamp, substantially
as herein-before described.
2. The adaptation of permutation or number locks for locking safety lamps, sub-
stantially as herein-before described.
In witness whereof, I, the said George William Smith, have hereunto set my
hand and seal, this Fourteenth day of August, in the year of our Lord
One thousand eight hundred and seventy-eight.
Witness,
WALLACE FAIRWEATHER, C.E.,
Patent Agent,
134, St. Vincent Street,
Glasgow.
GEO. W. SMITH. (L.S.)