55 
ANALYSIS OF A HYDEAULIC LIMESTONE CONCRETION FROM THE 
YORKSHIRE COAST, ^VITH REMARKS ON CONCRETIONS 
GENERALLY. BY II. 15. STOCKS, ESQ. 
In the lias of the Yorkshire Coast nodules of Hydraulic Lime- 
stone occur, these nodules when "burnt," form a good hj^draulic 
cement. The nodules are generally rounded, but flattened, grey 
and very hard, and contain the remains of ammonites, etc. 
Analysis of the Hydraulic Limestone of several localities have 
been made, but that from Yorkshire does not seem to have been 
examined. In continuation of my investigation into the chemical 
composition of various concretions, I have examined one of these 
from Sewerby, near Flamborough. A qualitative examination showed 
the presence of oxide of iron, alumina, lime, iron pyrites, sulphuric 
acid, carbonic acid, silicic acid and phosphoric acid. The estimations 
of the amounts of these constituents gave the following figures : — 
j Sowerby. 
Isle of 
i Sheppey. 
Ferric Oxide 
Ferrous Oxidk 
4-32 
ALU3IINA 
0-90 
O-3'.t 
Lime 
Soluble 
38-61 
37-ol 
Magnesia 
in 
0-79 
Silica 
Hydro- 
Carbonic Acid 
chloric 
31-7;) 
:i2-99 
Si LPHURic Acid 
Acid. 
Trace. 
Phosphoric Acid 
0-24 
Ferric Oxide \ 
2-90 
1-72 
Alumina 
Insol. 
11 (33 
4-32 
Lime 
iu 
n-().> 
Magnesia 
Hydro- 
0-37 
Silica 
chloric 
Hi -89 
Iron Pyrites ... 
Acid. 
1-87 1 
Water 
0-78 
Alkalies AND loss 
2-57 
0 <;."> 
100 00 
10000 
