Reviews — Geological Survey of India. 371 



On the whole then, I am no clearer about Faulting, Jointing and 

 Cleavage than I was before, but have had some difficulty in avoiding 

 being puzzled on points which were perfectly clear before. Not 

 so with a paper of M. Hebert, some time ago, which Mr. Teall 

 refers to, but Mr. Fisher ignores. Though short, it had this point 

 clearly brought out — that vertical pressure tends to produce direct, 

 horizontal pressure reverse, faults ; by this their relations to the 

 districts in which they occur are clearly seen. I have been led to 

 examine this paper of Mr. Fisher because it was apparently induced 

 by the appearance of Mr. Teall's slate, on which I should like to 

 say a word (see woodcut p. 367). It seems to me that instead of 

 the several series of faults being formed, at different epochs, we have 

 a clear illustration of the complex surroundings of one fault — the 

 main one — when the compactness of the slate prevents its utter 

 degradation into fault rock. I have copied the lines of faults as far 

 as I can make them out, and it will be seen, that though the right- 

 hand vertical fault (a) is a little shifted, yet others are not ; the 

 faults of the " B" set bifurcate on the right, and those of " ^i " on 

 the left, and some appear to belong to neither set. In a word, they 

 are all a series of minor faults, the fragments fitting as best they 

 may, and the whole is very similar to those produced experiment- 

 ally partly by direct pressure and partly by twisting, as figured in 

 Daubree's Geologic Experimentale. It is to be noted that the 

 bisection of the angles between the minor faults is pretty nearly 

 perpendicular to the main one. Whatever the interpretation, the 

 beautiful figure was a valuable new-year's gift to geologists, and is 

 worthily placed as Plate I. of the new Decade. 



la E V I IB 'W S. 



Memoirs o? the Geological Survey of India, Vol. XX. Part 2 ; 

 OR, Geological Notes on the Hills in the Neighbourhood 

 OF the Sind and Punjab Frontier between Quetta and 

 Dera GhIzi Khan. By W. T. Blanford, F.R.S., etc.. Deputy 

 Superintendent, Geological Survey of India. (Calcutta, 1883.) 



THIS Memoir has a more than usual interest as being the record 

 of the last field-work undertaken hj Mr. Blanford before his 

 final retirement from the Geological Survey of India, after a service 

 of more than twenty-seven years, during which he has not only 

 enriched the publications of the Survey with a large series of 

 valuable memoirs, but has also contributed most largely to our 

 knowledge of the existing mammals, birds, reptiles, and land and 

 freshwater molluscs of India and the adjacent countries. 



The country of which the geology is described in this memoir is 

 inhabited by turbulent frontier tribes, through whose territory it is 

 necessary to advance with the protection of an escort, and in which 

 there are some districts where it would be impossible to travel with- 

 out a considerable military force. Under these circumstances, the 

 movements of the geologist are considerably hampered ; and as Mr. 



