Lessons on Soil

by Edward J. Russell

Fig. 4. Clay was plastered over a square piece of board and completely covered it. After drying for a week the clay had shrunk and cracked

You must have found out by now how very slippery clay becomes as soon as it is wet enough. It is not easy to walk over a clay field in wet weather, and if the clay forms part of the slope of a hill it may be so slippery that it becomes dangerous. Sometimes after very heavy rains soil resting on clay on the side of a hill has begun to slide downwards and moves some distance before it stops. Fortunately these land slips as they are called, are not common in England, but they do occur. Fig. 6 shows one in the Isle of Wight, and another is described by Gilbert White in The Natural History of Selborne.