MR. H. B. WOODWARD ON THE 80ILS AND SUBSOILS OF NORFOLK. 413 
on a map would indicate 10 inches of line sandy loam, over 2 feet 
of gravel, over 4 feet of sand, full depth not proved. 
These German maps are, however, true geological or subsoil 
maps. They do not show the surface distribution of the soils, 
beyond what can be gathered from the numerous symbols marking 
points where trial holes or other observations were made. They 
are, however, of great value in showing the depth of soil, and 
also of the subsoils, so far as they would influence drainage 
and other agricultural operations. Undoubtedly maps of this kind 
are the most important that have been published, and, moreover, 
they are accompanied by detailed explanatory memoirs with 
analyses. 
Were a detailed map of the soils prepared, it would not, 
l believe, be so valuable by itself for appraising the agricultural 
capabilities of the land as a detailed subsoil map. The soil map 
would fail to give any idea of the structure of the ground and of 
the drainage. It would be easier to picture the general character 
of the soils from the subsoil map than to infer the nature and 
extent of the subsoils from the soil map. In estimating the 
capabilities of the land, the pervious or impervious nature of the 
subsoil is of the utmost importance. 
When acquaintance has been made with the character, thickness, 
and extent of the subsoils, and the way in which they have 
influenced the soil, with the extent of rainwash and the distribution 
of the underground water, then I think the geological surveyor 
may pass a rough and ready examination into the general agri- 
cultural characters of the land. He may even convince the farmer 
who cultivates a few acres that a geological survey may be useful, 
and that it is wrong to think that “ Government be allays a doin’ 
summut queer.” 
A detailed subsoil map on a scale of 6 inches to a mile, carefully 
and judiciously surveyed, should serve as a basis for special 
investigations of soils. On it the general characters of soils should 
be indicated, and where there is much landslipped material or 
considerable downwashes of the subsoils these should be marked. 
Sometimes downwashes of gravel from the uplands are of sufiicient 
importance to have shallow gravel-pits opened in them, or buildings 
may be erected on them- -and yet in ordinary geological maps, 
which profess to show the Drifts, this debris from higher grounds, 
