56 



and undulating country is not distinguished from fen-land. The 

 amount of alteration necessary would, however, be very slight 

 showing the real insignificance of these features on a large scale. 

 The watersheds of the different river systems are well shown by 

 this method. The land is in brown. The depths of the sea are 

 shown by contour lines, having the same interval, or about 42 

 fathoms, and the surface is coloured deeper in zones of 5,000 ft. 

 It shows well the shallowness of the North Sea, and even the 

 comparative shallowness of the S^agrerack in comparison with 

 the deep Atlantic basin some distance to the west of the British 

 Islands, and only broken by the submarine plateau which 

 culminates in the Island of St. Kilda. Accompanying the model 

 is a small map comprising the same area, which serves as an 

 index of localities. 



174. Geological model of the south-east of England, 

 and part of Prance, including the Weald and the Bas 

 Boulonnais. Founded upon the maps of the Ordnance, 

 Admiralty, and Geological Surveys, by "W.Topley, F.G.S., 

 Geological Survey of England and Wales, and James B. 

 Jordan, Mining Record Office. The topography by 

 John Bartholomew, F.R.G.S. Embossed by Henry F. 

 Brion, London. Horizontal scale. 1 in. to the 4 miles. 

 Vertical scale, 1 in. to 2,400 feet, or nearly nine times 

 the horizontal. Size, 34 in. by 18 in. 



E. 122. 1880. Published by E. Stanford. 



This model is constructed in a different manner from that by 

 which most models are made, in which the names, &c. are 

 marked on the modelling material itself. In this case the relief 

 of the country is first modelled on an unmarked surface, and 

 then an ordinary engraved and geologically coloured map, with 

 all the names of places and features that are usual on such maps, 

 is taken and pressed upon the surface when wet, so that without 

 tearing, it fits itself to the various elevations and depressions, and 

 thus partakes of the relief of the underlying model. There is an 

 index of colours, and the map is accompanied by a horizontal 

 section from the English Channel, near Seaford, to the Isle of 

 Sheppey, on the same horizontal scale as the model and vertical 

 scale, one half that of the model. The vertical sides of the 

 model are also utilised to indicate the geological section along 

 the boundary lines of the map. 



175. Model of the valley of the Thames, showing the 

 physical features and the geology, by James B. Jordan. 

 Constructed from contours drawn by W. Topley, F.G.S., 

 the geology reduced from the Geological Survey. Hori- 

 zontal scale, 4 miles to the inch. Vertical scale, 1 inch 



