T. RiGG 417 



Summary. 



The writer has cleinonstrated that the geological formations in this 

 district give rise to a series of related soils which exhibit this relation- 

 ship more closely in the mineral constituents than in the texture. 



This series of soils may be usually divided into two or more soil 

 formations having distinct characteristics which require different 

 agricultural treatment. Mechanical and chemical analyses have been 

 shown to define the soil formations very clearly, revealing striking 

 uniformity among samples taken from the same soil formation and 

 marking it ofi definitely from any other. 



The writer has found the geology of the district to differ in several 

 points from the unpublished draft sheets of the Geological Survey 

 Department. Reasons have been given for any change on the geological 

 map which the writer thinks desirable. 



The soil formations have been described and their agricultural 

 treatment correlated with the results of mechanical and chemical 

 analyses. 



Crop maps have been constructed showing the distribution of crops 

 over the various soil formations and the relationships between crop and 

 soil thus occurring have been described. The extent to which each 

 soil formation is used for market-garden culture has also been shown. 



The failure of the method of plotting the acreage of a crop indis- 

 criminately over the parish area, in the Biggleswade market-garden 

 district, has been demonstrated. 



In all county soil surveys where there are extensive " quarternary " 

 deposits, giving rise to variations in the soils overlying the geological 

 formations, or where numerous geological formations outcrop within a 

 small area, the writer would suggest that in addition to the ordinary 

 soil survey usually conducted one or two small areas of about 30 square 

 miles in country of typical variation should be minutely investigated 

 in the manner described above in the present paper. If this is done, 

 the author feels sure that many characteristics of soil and crop 

 relationships will be brought out which otherwise would escape notice. 



In conclusion, I have to thank Professor Wood for suggesting the 

 subject for research and for his helpful advice during the progress 

 of the work, and I wish also to thank Mr L. F. Newman who kindly 

 placed at my disposal his long experience of soil survey work. 



Journ. of Aario. Sci. vil 28 



