Reviews — Prof. Judd — On Volcanoes. ^ 561 



6. lo-neous Eocks. — Four colours would suffice. All colours to be 

 bright, deep and glossy — 



Basalt and Greenstone Dark Carmine. 



Trachyte, Felstone, etc Permanent Scarlet. 



Granite Vermilion. 



Modern Volcanic Rock Light Orange. 



7. The letter-notation of the formations should be based upon the 

 Eoiaan alphabet for sedimentary rocks, and upon the Greek 

 alphabet for eruptive rocks. The monogram of a formation should 

 be formed, as a rule, by the Initial Capital of the name of that 

 formation ; the subdivisions to be distinguished in addition to this 

 Initial Capital, by the initial small letter of the name of the sub- 

 division, by a numerical exponent or by both. The figures of the 

 numerical exponents to be always given in chronological order, — 

 1 representing the first or oldest subdivision. Example : 



J. Jurassic. 



Jl Lias, 



Jl- Middle Lias. 



8. This Committee approves of the proposal to issue a Geological 

 Atlas of Europe, under the authority of the Congress. 



Signed, A. C. Eamsat, President of the Committee. 



W. ToPLEY, Secretary. 



la IE "V" I IB "VT" s. 



I. — Volcanoes : What they are, and What they Teach. By 

 John W. Judd, F.E.S., Professor of Geology in the Eoyal School 

 of Mines. 8vo. pp. 382. With 9G Illustrations. (London : C. 

 Kegan Paul & Co., 188L) 



THE book before us possesses a twofold interest : firstly, as the 

 work of an ardent and rising geologist who has been favoured 

 ■with peculiar advantages, both of education and opportunity, for the 

 study of volcanic phenomena ; and, secondly, as having been written 

 at the inspiration of the most accomplished exponent of Vulcanology 

 in this country, the late Mr. G. Poulett-Scrope. If his venerated friend 

 and master in Geology could have been spared to enjoy one additional 

 pleasure before he passed away, nothing, we feel sure, could have 

 enhanced his happiness more than to have lived to see the issue of 

 the present volume by his friend and disciple Prof. Judd. Certainly, 

 in Mr. Poulett-Scrope's case, the dictum of Mark Antony must be 

 reversed, and we may indeed say of him, " The good he did lives 

 after him." 



It is only within the last hundred years that any rational or 

 intelligible views with regard to volcanos are to be found. Previous 

 to that time tliey were looked upon as " burning mountains," or as 

 the abode of some deity, or as the place of torment of some special 

 and heinous offender. 



To the early Greeks and Eomans the crater of iEtna marked the 

 spot where Typhon, the hundred-headed monster, lies buried, and 



DECADE II. TOL. VIII. NO. XII. 36 



