MR. H. B. WOODWARD ON THE SOILS AND SUBSOILS OF NORFOLK. 407 
which in old days had been contemptuously spoken of as 
“extraneous rubbish,” and which had been sadly neglected by the 
Geological Survey. Ilis work was carried on with equal vigour 
and enthusiasm in subsequent years by Searles Y. Wood, junior, 
who in 1865 had made a general survey of the Drifts in more 
than eight English counties, and a complete survey of Essex on 
the one-inch Ordnance Map. 
The Geological Survey had commenced its labours in the south- 
west of England in a region comparatively free from superficial 
deposits, and as their operations were extended towards the Midland 
Counties they found the solid geology to he so masked in places by 
Drift, that “Boundary wholly conjectural” or “Boundary every- 
where deeply hidden below drift” was inserted on maps published 
as late as 1865. This method called forth strong language from 
Wood, and no wonder when we know that the Drifts are sometimes 
from 100 to 250 feet thick. In such districts they have more 
influence on the land than tho so-called solid formations, and are 
then of far greater importance in reference to agriculture, local 
water supply, and sanitary questions. This is now fully recognized; 
but at the same time it must not he forgotten that in all these 
questions the solid formations, where they come to the surface, are 
of equal importance with the drifts. 
That the subsoils of Norfolk cannot be rapidly surveyed was 
the opinion of the older agriculturists, and we find that Wood’s 
first sketch survey was modified by the later detailed work which 
happily he induced Mr. F. W. llarmer tit undertake.* It is, 
perhaps, not surprising that the results of this work showed that 
Trimmer had failed to grasp the true sequence of the Drifts, as lie 
had grouped together the Cromer Till and the Upper or Chalky 
Boulder Clay as Lower Drift, and had placed the Contorted I h i ft and 
the mass of Glacial Sands and gravels as Upper Drift ; a difference 
of great importance in the elucidation of the structure of the 
county. 
In this connection 1 may mention that the Geological Survey 
commenced its labours in Norfolk in 1875, and closed them in 
1884, after a period of nine years, when no less than ten officers 
* A reduced copy of the geological map by Messrs Wood and Harmer 
was published by the Palseontographical Society in 1872. See Supplement 
to 8. V. Wood’s Crag Molluscs. 
D D 2 
