48 
of the hill, we should find the permanent level of the water in the 
well nearer and nearer to the surface, until next the river the 
water level and the surface might actually coincide. These are no 
fanciful theories, but are based upon a very large body of facts, 
and they hold good just as much in one part of the kingdom as in 
another. 
Local application. (1). Water Supply West of the Eden :—Near 
Penrith there are two types of rock-structure, which give rise to 
very different results so far as water supply is concerned. On the 
Keswick side of the Northern-Western Railway, there is a large tract 
of country over which most of the rain that falls is got rid of either 
by evaporation or by overflow. The rocks consist of rapid alter- 
nations of pervious beds and other strata more or less impervious, 
and consequently the water does not percolate far down through 
them before it is thrown out to the surface as springs. Over such 
a country as this, the chances of meeting with a good water supply 
by means of wells sunk into the so/id rock, are much too uncertain 
to be worth serious consideration. 
But between the North-Western Railway and the River Eden 
there is a large tract of country over which the rock is of a very 
different nature. The tract of hilly ground running northward 
from the Eamont, past Lazonby, consists of the Penrith Sandstone. 
This rock, which is not less than a thousand feet in thickness, 
overlies the impervious rocks just mentioned, and is tilted in such 
a manner as to bring its highest beds down along the River Eden, 
while its middle beds form much of the high ground of Penrith 
Beacon, and the hills to the north-west, and its base comes out 
near the North-Western Railway. The beds overlying it are 
impervious to water, or practically so. The Penrith Sandstone 
thus forms a thick sheet of pervious sandstone, enclosed between 
the impervious series below, and the equally impervious series of 
marls east of the Eden. 
The Sandstone itself is highly pervious to water, and as there 
are no beds of clay in it, or anything to stop the downward perco- 
lation of water, nearly every drop of rain that falls upon it begins 
to soak downward into the rock directly it falls, and is not arrested 
