136 
THE MODEL ROOMS. 
of obtaining the salt is simple enough. Fresh water is intro- 
duced into a subterranean excavation in the saliferous deposit, 
and the salt is thereby dissolved out from the gypseous marl, 
forming a brine, which is conducted by means of pipes to the 
evaporation works. 
Several geological and topographical Models are also placed in 
the centre of the room. One of the most interesting of these is a 
geological model of the Isle of Arran, constructed by the late 
Sir Andrew "Ramsay, when a young man unknown to science, 
and exhibited by him at the Glasgow meeting of the British 
Association in 1840. A geological model of Arthurs Seat, 
Edinburgh, will also be found here. In the front of the fire- 
place, and under a screen of wire ropes on the wall at the end of 
the room, stands a large Model showing the geological structure 
of part of the south coast of the Isle of Wight, stretching from 
Bonchurch to Sandown Bay, and illustrating the nature of the 
Undercliff. With this model may be studied another, repre- 
senting the coast between Sandown Bay and Whitecliff Bay, 
showing the Chalk in an almost vertical position, with the 
overlying Tertiary series : both models of the Isle of Wight 
were constructed by the late Captain Boscawen Ibbetson. A 
geological model of Mont Blanc, and a topographical model of 
the Alps and the Plains of Lombardy, presented by the late 
Ur. Fitton, are also placed here ; while near the end of the room 
stands a model, showing the great landslip at Axmouth, in 
South Devon, which occurred on Christmas Day 1839, and was 
described by Conybeare and Bucklancl. At the base of this is a 
small model, by Mr. T. Gibb, representing a peat-moss in 
Lanarkshire, which slipped in August, 1861. 
Along the Northern Wall of this Boom, under the range of 
of windows looking on to Piccadilly is a series of Cases containing 
tools employed in various mining districts. Near the entrance 
to Room B. is a case devoted to tools employed by the colliers in 
the North of England. Close to this stands a case of tools used 
by the metal miners of Cornwall. The next Case is appropriated 
to Saxon tools, and the succeeding case to the tools used in the 
lead mines of Debyshire and Flintshire. These are followed by 
a series of Mexican tools, and these in turn by examples of tools 
employed in the collieries of South Wales. Then follows a case 
containing mining tools used in Flintshire, and also a set of 
Russian tools. Finally, there is a Case devoted to the tools used 
at Schemnitz, in Hungary, where the mines yield ores of gold, 
silver, lead and copper. 
From the Eastern Model Room, the visitor enters the second 
apartment (B.), which is devoted chiefly to illustrations of 
colliery workings. Immediately facing the entrance is a model 
representing the physical features of a coal district, showing 
the outcrop of the beds of coal, and how they are affected by 
faults or troubles. Next to this stands a model representing 
part of the lead- mining district of Alston Moor, in Cumberland; 
