456 =P. G. Sanford—Analysis of Gault and Greensand. 
analysis of the deposit. This I have been enabled to do throngh the 
kindness of the manager (A. Sheridan, Esq.), who was good enough 
to send me a series of samples of the earth, and the various products 
prepared from it. The Nutfield Fullers Earth is a heavy blue or 
yellow clay, with a greasy feel and an earthy fracture. The sample 
No. 1 contained 27-47 per cent. and No. 2, 29:56 per cent. of water 
before drying. 
No. 1. Buue Earrs. 
Dried at 100° C Insoluble Residue. 
Insoluble Residue = 59°96 per cent.= (SiO, = 452-81 per cent. 
Tron (Fe203) = | Dente) INGO A = PEGs A 
Alumina (Al,03) =—oitG \Fe,0; = 1:30 ,, 
Lime, CaO Sy CaO — 7 coo mmeny 
Magnesia, MgO = 1-41 (Ngo = O88, 
Phosphoric acid, P20, = 0°27 \ Soluble os 
Sulphuric acid, SO; = 0-°04/ im acid, 59-96 
Sodic chloride, NaCl = 0:05 
Alkalies, K.0 — 0-74 
Combined water = 14:27 
No. 2. YreLtow Earra. 
: Dried at 100° C Insoluble Residue. 
Insoluble Residue = 76:18 per cent.= {Silica = 59°37 per cent. 
Tron, Fe203 Soke AlO, = 10°05 ,, 
Alumina es alsyr7 Fe.03 = 3°86 ,, 
Lime, CaO = 4:31 CaO elt OMe 
Magnesia, MgO = 1:05 MeO = teres 
BOZ = 0°14\{ Soluble —- 
S03 = 0-°07/ in acid. 76°18 
Salt, NaCl = 0-14 
Alkalies, K,O = (Oss 
Combined water =P sag 
100-05 
V.—ANALYSIS OF THE GAULT AND GREENSAND. 
By P. Geraxtp Sanrorp, F.I.C., F.C.S., 
Metallurgical Laboratory, Royal School of Mines. 
HE sample of Gault, of which the analysis is given below, was 
obtained from the Clay Pits at Dunton Green, which I visited 
with the “London Geological Field Class” during June last. At 
this place the Gault rests upon a bed of reddish yellow sand (Lower 
Greensand), which is mixed in certain proportions with the Gault 
clay to form bricks. This sand, of which I also give an analysis, is 
very moist when first taken from the bed, but very rapidly becomes 
dry, upon exposure to the air, so that it afterwards loses very little 
more water at 100°C. The Gault, as taken from the pit, contained 
26:68 per cent of moisture, but upon ignition of the dried substance, 
in a muffle furnace, it becomes so hard that it will scratch glass 
easily. 
