On the Banger of Hasty Generalization in Geology. 435 
was found, on which Mr Geikie lays so much stress, and is in- 
deed the point d'appui of his whole argument. Instead of 
finding this bed to be of marine origin and distinctly strati- 
fied, as Mr Geikie has described it, we found it (as any one 
can determine the fact for themselves) to consist of two dis- 
tinct beds. The lower one, which rests on gravel, is evidently a 
marsh silt due to the overflowing of the Water of Leith, the 
remains of which may still be seen about 100 yards to the 
west. That this marsh existed not in the Roman age, but 
within the memory of the oldest inhabitant, is rendered highly 
probable, by the situation bearing the name of Puddock Hall, 
evidently from its proximity to the abode of frogs. That this 
marsh silt was deposited long posterior to the Roman occupa- 
tion, we shall endeavour in the sequel to prove. The silt 
stratum or lower portion of bed (5) contains no remains of 
animals nor pieces of pottery ; v/hen dessicated by exposure to 
the air, it separates into prisms perpendicular to the clay-bed 
below, and is thus easily differentiated from the upper stratum 
in which Mr Geikie found the so-called Roman pottery. 
The upper portion of No. 5 is distinguished from its lower 
congener by numerous vesicular coal cinders, evidently acted 
on by heat, and as the matrix shows no symptoms of fusion 
from internal heat or otherwise, I take leave to denominate as 
simply coal ashes. Side by side with the incinerated coals we 
found oyster shells, not all lying flat, as deposited in a bed, but 
at all angles to the horizon, precisely as any one may find 
them in a humus bed, where a farmer, knowing their worth for 
manure, had shot them in at random. Nor were the stones, 
as Mr Geikie has said, lying on their sides (as would have 
been the case if this bed had been a lacustrine or marine de- 
posit) but were arranged in as higgledy-piggledy a manner 
as the oyster shells. We, with the assistance of Mr Field's 
men, had no difficulty in supplying ourselves with from 
thirty to forty specimens of pottery, also bones of sheep, the 
common ox(Bos taurus), teeth of the same, and also of the horse. 
Only one evidence of the deer was found, and that was a tooth. 
Before entering into the further proof of this bed being of 
very modern origin, let us consider first the occurrence of the 
burned coal so largely sprinkled through its mass, and ask 
