1907.] Soil Maps. 53 



The sole agents for advertisements are Messrs. Laughton 

 and Co., Ltd., 3, Wellington Street, Strand, W.C., to whom 

 all communications relating to advertisements should be 

 addressed. 



There are two classes of maps issued by the Geological 

 Survey : (1) The " Solid " maps, which show the distribution of 

 the solid rock foundations, and (2) the 

 Soil Maps " Drift " maps, which show the super- 



ficial deposits of clay, alluvium, gravel, 

 &c, which overlie the solid formations, 

 as well as the solid formations themselves when not so covered. 

 The utility of these drift maps is becoming more widely known 

 to those interested in agricultural investigation, as they are of 

 especial value as a basis for the construction of soil maps. 



The Board of Education have informed this department that, 

 since 1901, the preparation of maps, both on the 6-in. and the 

 i-in. scale in England and Scotland, has been carried on so as 

 to provide for the issue of drift editions. 



For England and Wales a large number of drift maps on 

 the i-in. scale have been published. For Scotland, drift 

 editions of the I -in. sheets 13, 21, and 55 have been issued, 

 and drift editions are being prepared of all the sheets now in 

 progress. In the case of the i-in. sheets prepared before 1901, 

 where materials are available for a drift edition, the Geological 

 Survey is working towards the publication of such maps. 

 For coal field areas 6-in. maps were published, and on these 

 the drift deposits were shown by stippling. The coal field 6-in , 

 tnaps are now under revision, and the sheets published after 

 revision show the drift boundary lines ; copies of these sheets, 

 showing the drifts in colour, can be obtained from the Ordnance 

 Survey Office. Southampton, on payment of the cost of prepara- 

 tion. 



Except as regards our or two small areas of special geological 

 interest in Scotland, the publication of 6-in. maps is restricted 

 in both England and Scotland to mining areas ; but the manu- 

 script 6-in. maps or the field maps of all published 1- in. sheets 

 are available for reference or for copying at the offices of the 

 Geological Survey, (Jennvn Street, London, S.W., or 3 3. ( ieorge 

 Square, Edinburgh). 



