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to the Eailway.* But these are not solitary instances. Diu-ing 

 the past winter two sHps have taken place within the distance 

 of a mile, on the north side of the valley of the Frome, above 

 Stroud ; one was an old slip, which appears to have moved at 

 intervals for several years. In that instance also, a mass of 

 Fullers Earth is passing downwards into the bottom of the valley, 

 and at the time of writing these notes it is moving at the rate 

 of nearly half-an-inch per day. Its progress is registered in this 

 manner : — a tree formerly grew at the edge of the shp, and it 

 took root partly in the firm soil, and partly in that which had 

 slipped, but which had, apparently, for a time, ceased to move. 

 Eventually the sUpping was resumed, and the tree was, in 

 consequence, split into two parts, the root of the portion which 

 is in the firm ground now makes a groove along the side of the 

 moving clay, and by marking the clay close to the root, the 

 progress of the slip from day to day can be accurately measured. 

 P Slips from the Fullers Earth are so numerous that it is 

 scarcely possible to find a combe or hollow on a slope, capped 

 by that formation and the Great Oolite, in which there are not 

 one or more slips. Sometimes they are stationary, but frequently 

 in winter, after heavy rains and severe frost, they move a little 

 forward, until, in course of time, the masses reach the bottom 

 of the valleys, where they are eroded by the streams. A good 

 illustration occurs in the Shortwood Valley, above Nailsworth, 

 where, in 1845, an old sKp, some 25 to 30 yards wide, and of 

 considerable length, moved downwards, until its lower part filled 

 the bed of the stream, and so dammed it as to form a small 

 pond. Since this date the stream has been clearing out its 

 channel, and, as the work proceeds, smaller slips from the old 

 one periodically take place, so that the process repeats itself in 

 detail. In short, wherever the Fullers Earth is still in position 

 on the escarpments, a great portion of the slopes are at intervals 

 in a state of movement. 



* See notes in postcript, in which more detailed information respecting this slip 

 is given by Mr. G. F. Playne who has been observing it from the time when its 

 • recent movement commenced. 



