Il6 MR. F. W. HARMER ON THE GLACIAL DEPOSITS 
Fig. 4. — Map showing the distribution of the Purple Clay (North 
Sea Drift), and of the Chalky boulder-clay of the East of England. — 
S. V. Wood, Jun. 
The arrows show the suggested direction of the ice flow. Reproduced by 
permission of the Council of the Geological Society. 
