Undulating or Hilly Ground. 303 
climate. On the shores of the Baltic, in the neighbourhood 
of Memel, I remember to have seen hills of sand about 100 
feet high ; but these I consider to be natural elevations of 
the ground, covered with sand, for I only found them at one 
point. 
The conditions required for the formation of sand-hills on 
a sea-board are, a flat coast, a scanty sea-chafed beach, and 
a stormy atmosphere. To those who are familiar with dif- 
ferent forms of beaches, localities will suggest themselves, 
where, owing to the want of one of the conditions required, 
there are no sand-hills. At our headlands, for example— 
Ardnamurchan, Point of Ross, the Ormshead—where the 
winds and waves play in their “ wildest and angriest moods,” 
sand can find no resting-place. Again, in the estuaries of 
the Dee, the Mersey, the Forth, and Morecambe bay, there is 
abundance of sand reposing on a flat sea-beach ; but in these 
places the winds have not force enough to detach the sand 
and carry it above high-water mark in sufficient quantity to 
form hills. 
_A question of interest in this inquiry, but which is not 
easily determined, is the supply of sand from the sea-board 
requisite for the maintenance of a belt of sand-hills. The 
_ ground on the landward side of such a belt shows that there 
is a transfer of sand to the inland, and when it meets a low 
wall it rises over it; where it meets a high fence wall, the 
sand is thrown back into a ridge about two feet from the 
base of the wall. If the quantity of sand annually carried 
inland could be ascertained, then, where the condition of the 
sand-hills are stationary, that would measure the supply 
from the sea-chafed beach. 
I fear that the view that the Pyramids were erected by the 
ancient Egyptians to stay the progress of sand from the 
Desert finds no support from the foregoing remarks ; for in 
their forms they approach to the sand domes which offer the 
least possible resistance to winds. And the masonry in the 
Pyramids, arranged as a series of dikes, these in time to 
become sand ridges, would check the advance of sand from 
the Desert more than if the materials were put in the form 
