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The Geological Survey of England and Wales. 
In the Chalk area of Hampshire, Mr. Hawkins, by mapping out 
these horizons, has proved the general accuracy of the interpretation 
of the structure of that region given by Hr. Barrois. The uprise at 
Winchester is well marked, Lower Chalk being there brought to 
the surface. The folds traversing the Chalk in the western part of 
the Hampshire Basin, though more strongly marked than those 
of the London Basin, can only be satisfactorily made out by mapping 
the subdivisions of the Chalk. Some of the ruptures attendant on 
the plication of the rocks, so marked in Dorsetshire, are prolonged 
even into Sussex, and have been detected by Mr. Reid as far east 
as Eastbourne, where on the foreshore the Cretaceous strata are 
repeated by faults and overthrusts. 
It seems not impossible that the detailed and accurate mapping 
of the disturbances in the Chalk may ultimately give a clue to the 
depths of the underlying Palaeozoic rocks, a question of the utmost 
practical importance in regard to the tracing of coal-bearing deposits 
beneath the South of England. 
In 1891 phosphatic Chalk, closely resembling that which is 
commercially worked in the North of France and in Belgium, was 
noticed for the first time in this country by Mr. Strahan. The bed 
is exposed in a Chalk-pit at Taplow, but at present has not been 
detected elsewhere. 
The relations of the Gault and Upper Greensand have long been 
a matter of uncertainty. Mr. Bristow, the late Senior Director, 
believed that the two were really one formation, one being locally 
developed at the expense of the other. Mr. Godwin- Austen 
regarded the Upper Greensand as a shore-deposit, in part contem- 
poraneous with the Gault of deeper waters. Other geologists have 
expressed similar views. These opinions have received support from 
our recent Surveys. The upper part of the Gault becomes more 
sandy to the west, and was there mapped as Upper Greensand, 
the clay coloured as Gault in Wiltshire representing only about the 
lower third part of the Gault of Folkestone. This clay becomes so 
thin to the west that it cannot be separately mapped. 
Mr. Jukes-Browne makes three divisions of the Gault and 
Upper Greensand Series, which are now found to constitute really 
one formation : — 
3. Greensauds and Sandstone, and Chert-beds (Zone of Pecten asper). 
2. Buff Sands, Malmstones, and Silty Marls ; the last representing the 
Upper Gault (Zone of Ammonites rostratus). 
1. Lower Gault Clays (Zone of Ammonites lautus and Amm. 
interruptus). 
The Chert-beds of Wiltshire and Devonshire are local develop- 
ments in the Zone of Pecten asper. They are not found in Dorset ; 
but they attain importance in the Isle of Wight, and were there 
separately mapped by Mr. Strahan. 
In the neighbourhood of Devizes the subdivisions of the Upper 
Greensand are well marked. The lower one, or “ Malmstone,” 
contains, especially in the lower part, colloid silica in the form of 
small round globules and sponge spicules, sometimes to the extent 
