138 
THE MODEL BOOMS. 
models, but are now temporarily occupied by statistical diagrams 
bearing on our coal production, and by some large slabs of 
■stone showing ripple-marks, &c. 
Against the opposite wall is arranged a large collection of 
miner s’ safety lamps , transferred to the Museum by the Royal 
Commission on Accidents in Mines, under the chairmanship of 
the late Sir Warington Smyth. The collection includes most 
of the lamps which were practically tested by the Commissioners 
and referred to in their Report. 
In order to reach the Galleries the visitor should ascend the 
spiral staircase in the north-east corner of the first Model 
Room A. The arrangement of the Galleries is at present in a 
transitional condition — a remark which is applicable to the 
Model Rooms generally ; and hence the notice of the present 
condition of this section of the Museum need be but brief. In 
The Gallery of Room A., the Wall Cases are devoted to the 
display of a series of large specimens showing the successive 
stages in the manufacture of crown and sheet glass, with 
examples of the workmen’s tools. The Cases on the balustrade 
of the Gallery contain, at present, a series of Sopwith’s models 
illustrating geological phenomena, and some miscellaneous 
mining instruments. At the western end of this Gallery is a 
Glass Case filled with a large series of crystallographic models 
in wood and glass ; and there is also a small set of Mr. J ordan’s 
models in coloured cardboard. 
On passing to the Gallery of Room B. the visitor finds the 
Wall Cases on his left hand devoted to a large series of 
specimens, in course of arrangement, illustrating the use of 
clays in the manufacture of bricks. With these will be 
found a collection of fire-bricks and crucibles, illustrating the 
use of highly refractory materials, like the Stourbridge fire-clay. 
The fire-clays are commonly supposed to represent the exhausted 
soils of the coal-measure forests. A Bath brick is here exhibited 
by the side of a sample of the siliceous silt of the River Par ret, 
from which such bricks are made at Bridgewater in Somerset- 
shire. The bricks are said to be named after a Mr. Bath, who 
originally made them. There is also shown here a specimen of 
dliatomite, or diatomaceous deposit from the bed of a lake in 
Skye. This material consists of the minute siliceous cases 
(frustules) of the unicellular algae known as diatoms, and is 
employed as a refractory material for fire-proof structures, and 
has been used, as an absorbent for nitro-glycerine in the 
preparation of dynamite. 
The Cases on the Gallery-balustrade contain an extensive collec- 
tion of mineral phosphates, presented recently by Mr. Hoyer 
Millar, and a series illustrating the varieties and uses of borax, 
collected by Mr. Fleming, and referred to in a paper which he 
read before the Society of Arts in 1891. 
