154 ABSENCE OF WATERFALLS 



by the mountain lake or tarn, or by the elevated bog 

 (acting like a sponge), reposing on high table lands. These 

 resources are very frequently caused by a succession of hard 

 beds, forming as it were the edges of the basin and 

 husbanding the supply. If there is no hard rim the edges 

 are in course of time worn away ; and so, on the other 

 hand, if there is only one hard line or ridge, the water 

 falls as from the sides of the roof of a house, and there 

 is no constant supply. The Malvern Hills are an illustration 

 of the latter state of things. The principal rock syenite 

 is hard enough, but as the hills are the result of one 

 line of abrupt elevation (dividing Gloucestershire and Wor- 

 cestershire on the east and south from Herefordshire on 

 the west), and of subsequent denudation, the rain water 

 flows off at once from the axial line, and there are no 

 natural store-houses for streams, and no waterfalls, and 

 the district is scantily supplied with water, as most resi- 

 dents and visitors become painfully aware. On the higher 

 ridges of North Staffordshire, although there is no such 

 axial line, the sandstone edges of the original basins have 

 been weathered down, and there are few elevated natural 

 pools to be met with none of any large size. For an 

 example of a natural basin keeping up a constant supply 

 of the mechanical power water to saw through and 

 scrape away the softer materials in its course, I may refer 

 to Llyn Conwy, a lake which probably no member of the 

 North Staffordshire Field Naturalists' Club ever saw, as 

 it lies in a remote district, out of sight of any road, and 

 possesses no attraction beyond those incident to a sheet 

 of water with wild, weather-beaten boundaries. It is the 

 parent of my dearly-beloved river Conwy, and is a natural 

 basin on table land at a very considerable elevation, with 

 its edges formed by the igneous rock. If, therefore, I 

 were compelled to answer the question myself in concise 



