PLATE 10 



Fig. 1. From right to left, cylinders 1, 2, and 3 maintained at 14 per cent 

 of soil moisture, and cylinders 4, 5, and 6 maintained at 16 per cent of soil 

 moisture. 



Fig. 2. From right to left again, cylinders 1, 2, and 3 maintained at 18 per 

 cent of soil moisture, and cylinders 4, 5, and 6 maintained at 20 per cent of soil 

 moisture. Part of cylinder 7 shoeing 22 per cent of soil moisture. 



[34] 



