28 
MR. SOPWITH's model OF THE FOREST OF DEAN. 
Mr. SOPWITH said, he regretted that he could not exhibit 
the model on the table, so that it might be well seen by all 
present, but he would endeavour to explain it. It repre- 
sented the Forest of Dean, in Grloucestershire, on a scale in 
which each five inches represented a mile. The surface was 
divided into square miles, to measure the extent, and shew 
the relative position of the places. The various colours re- 
presented the enclosures, the villages, towns, &c. The ends 
and middle were parted, to represent the sections of the 
strata. They shewed the old red sandstone, of which the 
thickness was considerable, and which was overlaid by the 
mountain limestone and coal beds, of which the commence- 
ment was here seen. To shew the structure of the forest from 
North to South, Mr. Sopwith exhibited the section of the 
centre of the model, where the beds of coal were represented 
by black lines. The outcrops of the various seams of coal 
were shewn on the surface, and the sections of them in the 
North and South position. In constructing drawings, two 
portions were made apparent ; but from above the model, 
they might see the stratification on both sides. The surface 
of the model was made to come off, to shew the situation of 
the different seams of coal. The portion first taken off re- 
presented the part of the surface, with the rocks down to the 
first vein of coal. When this portion was removed, the 
upper seam of coal was disclosed. The first seam being 
taken off, disclosed another seam under it, which also was 
removed, and so on to the lowest bed of coal, where was 
shewn the outcropping and under strata, with the lines of 
the water levels. This exhibited a continuous bed, about 
six miles in one direction, and three or four miles in the 
other, forming a basin of coal. He would now say a few 
