Reviews — Geology of East Africa Protectorate. 275 



Geology. — The geology of the Day Dawn district differs materially 

 from that of Cue, the granodiorite of the latter being entirely absent. 

 The whole area is therefore classed as greenstone, with its schistose 

 and altered forms due to hydration and the attendant forces, such as 

 compression, elongation, crashing, and shearing. The term greenstone 

 is meant to include not only the normal hornblende schists, amphibo- 

 lites, etc., but also the diorites, diabases, and andesites which occur 

 in this district, though they are generally so highly altered at the 

 surface as to render the delineation of their boundaries a very 

 difficult task. 



The amphibolites are highly foliated and hydrated near the surface. 

 A magmatic igneous intrusion occurs, composed probably of diabase, 

 the augite of which has been changed into hornblende and epidote. 

 The lodes of the district occur in the " igneous zone," in the " contact 

 zone," and in the " amphibolite zone," the principal productive 

 mines being contained in the contact zone, in which, though there 

 are only eight gold-bearing reefs, the production is 97 per cent, of the 

 total jdeld. 



Section II is devoted to a full description of the productive mines 

 of the district, and it concludes with two appendices containing 

 (1) a list of the Cue rocks, (2) notes on some typical Cue rocks, by 

 E. S. Simpson, F.C.S. 



This report is also well illustrated, 



"We must congratulate Mr. Woodward upon the ability with which 

 he has conducted the survey of this important mining area. He has 

 shown no less a grasp of the economic problems presented to him in 

 the course of his work than of the geological ones. 



A. H. P. 



IV. — Eepoet eelating to the Geology of the East Africa Peo- 

 TECTOEATE. By H. Beantwood Muff, B.A. Colonial Eeports — 

 Miscellaneous. No. 45, East Africa Protectorate. London : 

 H.M. Stationary Office, 1908. With map and 2 text-illustrations. 

 Price &d. 



WE welcome the publication of this important and interesting 

 report, which has been issued at a price that may be regarded 

 as exemplary. 



Mr. Muff was engaged between December, 1905, and September, 

 1906, in investigating the geology of the East Africa Protectorate, 

 mainly with the object of reporting on the prospects of obtaining better 

 supplies of water for drinking and other purposes. The region consists 

 of a long but comparatively narrow belt of country, extending from 

 the Island of Mombasa on the coast of the Indian Ocean to Port 

 Florence on Yictoria Nyanza, a distance of 580 miles as measured 

 along the course of the Uganda railway. 



This region comprises (1) the coastal helt formed of raised coral 

 rock and sands, followed inland by a mass of shales and underlying 

 sandstones, with occasional limestones, that dip towards the coast, and 

 are in great part of Jurassic and in part probably of Triassic age. This 

 coastal belt extends for 57 miles, and rises to over 1,000 feet above 

 sea-level. 



