Account of the Effect of a Bitiuninous Shale. 
277 
Oxford clay formation, which underlies the coral-rag gravel. In the 
course of the ensuing summer the gravel, which had been thrown out of 
the cutting upon the land, being much esteemed, was all carted away, 
but liie shale was left undisturbed. Late in the winter, or early in the 
spring, an a])plication was made to me by tlie tenant of tlic land for au 
allowance for the expense of carting away the shale which encumbered 
it, when, accompanied by the bailiff, I repaired to the meadow in order 
to ascertain what was fitting to be done. I observed with interest around 
the edge of each heap a circle of dark green and luxuriant grass, such as 
would have surrounded a heap of rich manure. I also observed that 
the frost was breaking down the shale into powder. These circumstances 
I pointed out to the farmer as indicative of a fertilising property in the 
substance, and, recommending him to draw it out on his land imme- 
diately, I declined making him any allowance. A few months after- 
wards I learned that lie had followed my advice, with the excellent 
result of a heavy crop of hay and aftergrass, which I witnessed with 
satisfaction. He died not long after ; his occupation is now subdivided 
between contiguous tenants, and I am unable to give you more than this 
my general recollection. I may add that, when I was impressed with 
the fertilising properties of the shale, I also saw that it was bituminous, 
and found that upon placing a fragment in the fire, it emitted consider- 
able flame. I have now procured a lump of it, and have had it exa- 
mined by a friend, a very accomplished chemist, who informs me that a 
proximate analysis brings out the following results : — 
Combustible matter, chiefly bituminous . 206 
Silica 321 
Alumina . . . . . . 130 
Lime . . . . . .116 
Oxide of iron . » . . .109 
Magnesia ...... 5 
Carbonic Acid, &c. .... 73 
Water 40 
Phosphoric acid and alkaline salts, a trace. 
1000 
which may be taken as a near expression of its constituents. 
It seems to be very probable that this substance owes its fertilising 
properties mainly to the bituminous matter which enters so largely into 
its composition. It is not of unfrequent occurrence, and may be de- 
serving of attention. The bituminous shale so common in coal-mea- 
sures, when possessed of the property of breaking down by the action of 
frost, may be very useful upon gravelly soils. 
St. Jameses Street, London, 
March 31, 1843. 
