64

THE COLLIERY GUARDIAN.

July 14, 1916.

APPROVED SAFETY LAMPS.

In pursuance of section 33 of the Coal Mines Act,
1911, the Home Secretary has made an Order approving
certain new types of safety lamps, until further Order,
for use in all mines to which the Act applies, subject in
each case to the conditions specified in the schedule.
The schedules to the Safety Lamps Orders of August 26,
1913; March 16, 1914; July 1,1914; October 7, 1914;
March 16, 1915, and June 15, 1915—shall take effect
subject to the amendments set forth in Part III. The
term “ glasses of approved type ” means glasses of a
type approved for use with a flame safety lamp by an
Order made under section 33 of the Act.

The Order may be cited as “ The Safety Lamps Order
of the 15th May, 1916.”

Part L—Flame Safety Lamps approved, (a) for General
Use, (6) for use by Officials Only.

Messrs. Best's “ Excelsior ” Lamp No. 3.

This lamp, the general design
fig. 1, consists of the following
essential parts:—

(1)	Bonnet or Shield of
seamless steel or other suit-
able metal, furnished with out-
let holes and two rows of inlet
holes between 2 and 3 inches
from the bottom, of a total
area of not more than 2^ square
inches, protected by an external
baffle ring. The whole bonnet
is covered with “ Best’s Patent
Cooling Bonnet” or cap of
steel, or other suitable metal,
which is heat-insulated.

(2)	Bonnet or Middle Ring
of brass, steel, or iron, riveted
to the bonnet and provided
with 30 air-inlet holes each
T3g in. in diameter.

Pillars of brass, steel or iron,
four or more, so arranged that
a straight line touching the
exterior parts of consecutive
pillars does not touch the
glass.

Bottom Ring of brass, steel
or iron.

(3)	Gauze, of not less than

of which is shown in

Fig. 1.—Best’s
“Excelsior” No. 3.



28 S.W.G. steel, or best charcoal annealed iron
wire, 784 meshes to the square inch.

Internal Dimensions.

Height from shoulder of the base ring ... 4| in. ± | in.

Diameter at top ......................... 2 in. ijain.

Diameter at bottom ...................... 2|in. ±ygin.

Chimney.—Best’s perforated air-feed chimney of
brass, copper, or other suitable metal, with horizontal
perforated plate and a perforated cylindrical portion not
more than 1| in. wide.

Internal Dimensions.

Height from shoulder of base ring to hori-

zontal plate .......................... l|in. ± i in.

Height above horizontal plate when in position 21 in ± |in.
Diameter at top ......................... lin. ±/gin.

Diameter at bottom ...................... Ijin. ±jgin

(4)	Glasses of approved type, two, cylindrical in form
and within the dimension limits, and bearing respec-
tively the size marks specified below, arranged as
shown in fig. 1.

Inner glass	Outer glass.

External diameter... 37mm. £	j 57mm. | * imm

Height............. 45 mm. ±|mm. 67 mm. ±|mm.

Size mark ......... 37—45 *	57—67

(5)	Glass Retaining Ring of brass, steel or iron. The
ring carries a metal dome, which has a flanged seating
for the inner glass. A flexible washer is placed on the
base of the dome and forms the seating on which rests
the outer glass, the lower part of the dome being
perforated to allow air to pass to the flame.

(6)	Oil Vessel, of brass, steel or iron, of capacity
sufficient to provide the required light for the required
time. Fitted with a round burner about | in. in
diameter, or with a flat burner not more than | in.
Fitted or not with a pricker or regulator (together or
singly) ; provided or not with an electric igniter of
approved type.

(7)	Locking Device.—A. magnetic lock so constructed
that the bolt can be withdrawn only by means of a
powerful electro-magnet.

The strength of material and attachments throughout
the lamp must be not less than in the samples sub-
mitted for the official tests on January 19,1915, and
March 3, 1916. The lamp must be capable of main-
taining a light of candle-power not less than 0*30, as
determined by a pentane standard, all round in a
horizontal plane throughout a period of not less than
10 hours. The lamp must be made at the works of
Messrs. Best’s Safety Lamps Limited, at Providence
Works, Park Lane Mills, Leeds, and must be marked
with its name and the name of the maker.

Best's “ Gauzeless" Lamps No. 1 and No. la.

This lamp (fig. 2) is a modification of Best’s
“Excelsior” lamp No. 3, and differs therefrom only in
the following arrangements, whereby perforated plates
are used in substitution for the usual gauzes :—

(1)	Admission of air to the lamp-flame is through :—

(a) A perforated cylinder of copper 2 in. long and
not less than -^in. thick, the lower rim of which
forms a secure seating for the upper edge of the
outer glass. The perforated portions are arranged
horizontally and vertically. The horizontal portion
forms a cover to the cylinder, and is a securely
soldered ring not more than j in. wide and of external

diameter not more than 2 in., there being not more
than 400 perforations per square inch, each perfora-
tion being not more than 5% in. in diameter. The
vertical perforated portion is not more than 1 in. in
width, there being not more than 200 perforations per
square inch, each perforation being not more than
3~ in. in diameter ; and

(b) A perforated conical plate of copper securely
soldered to the base-plate glass tightening ring

poo OOO (

Fig. 2.

Best’s Gauzeless

Lamp No. 1.

10 0 000
)000

between the two glasses, not
less than in. thick, there
being not more than 200
perforations per square
inch, each perforation being
not more than in. in
diameter.

(2)	Passage of the products
of combustion is through:—

(a)	A parallel chimney of
copper not less than in.
thick, with a coned cap
screwed or otherwise attached
to the top, the lower rim of
the chimney forming a secure
seating for the upper edge of
the inner glass by means of a
spring compression device.
The total length of the
chimney is 4in., its interna]
diameter at the bottom J in.,
and its internal diameter at
the top of the conical cap
J in.; and

(b)	A horizontal perforated
plate of copper not more than .

2 in. in diameter, and not less
than s’q in. thick, attached to
the top of the chimney by a
conical fitting of copper to
which it is securely fixed in
such a manner that the distance between the plate
and the top of the chimney is f in. The number of
the perforations does not exceed 200 per square inch,
and the diameter of each perforation does not
exceed in.

The oil vessel may be fitted with either a round or a
flat burner, which may project above the dome or not.

In the case of lamp No. 1a which shah be used by
surveyors and officials only, the body of the lamp may
be of aluminium or other suitable metal, and the lock
may be non-magnetic of an approved type.

The strength of material and attachments throughout
each lamp must be not less than in the samples sub-
mitted for the official tests on April 3,1916. Each lamp
must be capable of maintaining a light of candle-power
not less than 0’30 as determined by a pentane standa* d
all round in a horizontal plane throughout a period of
not less than 10 hours. The lamps must have been made
at the works of Messrs. Best’s Safety Lamps Limited, at
Providence Works, Park-lane Mills, Leeds, and each
lamp must be marked with its name and the name of
the maker.

Messrs. J. H. Rothwell and Co.'s “A3,” “ B3,” “ C3,”
“ D3," and “ E3 ” Lamps.

These lamps are modifications of Messrs. J. H.
Rothwell and Co.’s “ A,” “ B,” “ C,” “ D,” and “ E ”

Gauze
~~Co^ered

HALF ELEVATION. HALF SECTION.

PLAN OF MIDDLE.

Fig. 3.—Rothwell’s Lamps.

Types A3, B3, C3, D3 and E3.

lamps,* respectively,
and differ from them
only in having addi-
tional air-inlet holes
in the bonnet, as
shown in fig. 3, pro-
tected by gauze and
by an outer cover
riveted to the bonnet.

The strength of
material and attach-
ments throughout
each lamp is not less
than in the samples
submitted for the
official tests on Sep-
tember 30,1915. Each
lamp must be capable
of maintaining a light
of candle-power not
less than 0*30 as
determined by a pen-
tane standard all
round in a horizontal
plane throughout a
period of not less
than 10 hours. The
lamps must have been
made at the works of
Messrs. J. H. Roth-
well and Co., at
Swinton, near Man-
chester, and each
lamp must be marked
with its name and the

name of the maker.

“ Prestwich Patent Protector OS ” Lamp.

This lamp is a modification of the “ Prestwich Patent
Protector” lamp,t and is similar to it in all but the
following respects:—

(1)	The Pillar Ring is provided with air-inlet holes of
total area not greater than 1’4 sq. in.

(2)	Pillars.—Four or more (one sliding), so arranged
that a straight line touching the exterior parts of con-
secutive pillars does not touch the glass.

* See Colliery Guardian, October 10,1913, p. 737.

f See Colliery Guardian, September 26, 1913, p. 643.

(3) Dimensions of Gauzes.—

Outer gauze.

Height from shoulder of the
base ring ............... 4 in.	± 1 in.

Diameter at top............ 2|	in.	± |	in.

Diameter at bottom ...... 2| in.	± | in.

Inner gauze.

3| in. ± | in
1| in. ± t in’
If in. ± | in’

(4)	Glasses.—The lamp may be so constructed as to
be fitted with glasses 70 mm. ± J mm. in height.

(5)	Spirit or Oil Vessel.—Fitted with a flat or round
J to in. burner. Fitted or not with an electric
igniter of approved type.

The strength of material and attachments throughout
the lamp must be not less than in the samples submitted
for the official tests on January 10, 1916. The lamp
must be capable of maintaining a light of candle-power
not less than 0 30 as determined by a penfane standard
all round in a horizontal plane throughout a period of
not less than 10 hours. The lamp must have been
made at the works of the Protector Lamp and Lighting
Company Limited, at Eccles, near Manchester, and
must be marked with its name and the name of the

maker.

Messrs. Teale's Mueseler or Thornburry Lamps No. 6
and No. 6a.

The general design of this lamp is shown in fig. 4. It
is a bonneted Mueseler lamp with a double glass, a
gauze circle being fixed at the base between the two
glasses. The air-feed is through vertical or horizontal
holes, or both, in the middle ring. The lamp consists
of the following essential parts :—

(1)	Bonnet or Shield, of riveted steel, with a separate
securely-riveted crown, furnished with outlet holes
immediately below the crown, the lower edges of the
holes being not less than T3^ in. above the top of the
gauze. The lamp may also be fitted with a screw-off
bonnet locked by a sliding pillar.

(2)	Middle Ring, of brass, steel or iron, riveted to the
bonnet and provided with either vertical or horizontal
inlet holes, or both. A shut-off ring may be fitted.

HALF ELEVATION I HALF SECTION

I

w

Fig. 4.—Teale's Mueseler or Thornburry
No. 6 Lamp.

Pillars, oi brass, steel or iron, so arranged that a
straight line touching the exterior parts of consecutive
pillars does not touch the glass.

Bottom Ring, Qi brass, steel or iron.

(3)	Gauze of not less than 28 S.W.G. steel wire, 784
meshes to the square inch.

Internal Dimensions.

Height to shoulder of base ring........... 5|	in.	± | in.

Diameter at top .......................... 2	in.	± f in.

Diameter at bottom ....................... 2f	in.	± | in.

Mueseler Chimney, with horizontal perforated
diaphragm.

Dimensions.

Height above diaphragm, not less than 5 in.

Height below diaphragm, not less than in.
Diameter at top, not grea’er than j in.

Diameter at bottom, not gi eater than 1R in.

The lamp may also be used as a Mueseler lamp by
dispensing with the inside glass (see below) and pro-
viding the chimney with a horizontal gauze in place of
the perforated diaphragm.

(4)	Glasses, Qi approved type, two, arranged as shown
in fig. 4, cylindrical in form and within the dimension
limits and bearing respectively the size marks specified
below. Each glass provided with top and bottom
asbestos washers to ensure flame-tight joints with the
gauze, chimney and retaining ring.

Inner glass. Outer glass.
External diameter... 51 mm. £ 2. J j 70 mm. | j
Height ........... 60 mm. ± |mm. 60mm. ± fnim.

Size mark......... 51—60	70—60

The lamp may also be made to take glasses 62 mm.
(± | mm.) high, in which case the size marks of the
glasses are 51-62 (inner), and 70-62 (outer).

(5)	Glass Retaining Ring, Qi brass, screw-threaded to
fit the bottom ring. Furnished with slots protected by
a securely fastened horizontal gauze of not less than
28 S.W.G. steel wire, 784 meshes to the square inch.

(6)	Oil Vessel, Qi brass, of capacity sufficient to
provide the required light for the required time as
specified below. Fitted with a T5K—/(T-inch flat burner,
with or without a domed reflector. An electric igniter
of approved type may be fitted.

(7)	Locking Device.—Lead-rivet or magnetic lock of
any of the types previously approved for use with
approved safety lamps.