By A. J. Jukes-Browne, B.A., F.G.S8. 319 
an explanation of these I must direct attention to the sections, 
Section 1 shows the natural order of the strata which lie beneath 
Devizes. Beds of rock are not generally vertical masses, but layers 
or courses which run one under another, and are continuous, hori- 
zontally or obliquely, for a great distance underground. Thus 
bed @ in the diagram, which is called the Kimeridge Clay, and 
comes to the surface between Seend and Poulshot, would be found 
under Devizes if anyone made a boring down to the level at which 
it occurs, and a geologist can generally estimate the depth at which 
any such bed can be found. 
The other section before you is one through Morgan’s Hill, and 
shows the successive beds of Chalk of which ‘it is composed, the 
lowest of them resting on the same bed of green Sand which comes 
to the surface round Devizes and Bishops Cannings. 
The rocks in the immediate neighbourhood of Devizes belong to 
the Cretaceous System, and for the purposes of description they may 
be dealt with under the following names, in descending order :— 
7. Upper Chalk. 3. Malmstone, 
6. Middle Chalk. 2. Gault. 
5. Lower Chalk. 1, Ironsands. 
4, Greensand. 
1.—Ironsands. The lowest beds of the system are the brown 
pebbly Sandstones of Poulshot and Rowde, with the outlying patch 
at Seend. The pebbles in these beds are chiefly small rounded bits of 
vein-Quartz which have been derived from much older rocks that lie 
to the west of Wiltshire. Fossils are rare in them, and they would 
have been credited with few organic remains if Mr. W. Cunnington 
had not been careful to collect from the cutting made for the road 
up Seend Hill in 1849, This is an excellent instance of the useful 
work which a local geologist can accomplish, and the geological 
members of every local Natural History Society ought to consider 
it their duty to record and collect from all such exposures while they 
are fresh and clear. If they do not, valuable and interesting facts 
are lost to science, for the banks become obscured with earth and 
grass in the course of a few years, when the geologist who then 
