220 Reviews — T. A. BlyWs Metallography. 



Y. gracilis, Carr. 1. c. ; pi. Iv. fig. 2. Lias. Lyme Regis, Dorsetshire. 



Y. Joassiana, Carr. 1. c. ; pi. Iv. fig. 8 and 9. Coral Rag. Brora, Sutherland- 

 shire. 



Y. Morrisii, Carr. 1. c. ; pi. Iv. fig. 3-6, Lower Greensand. Potton, Cambridge- 

 shire. 



Zamia gigas, Lindl. and Hutt. Trans. Linn. Soc. vol. xxvi. p. 663 ; pi. lii. and 

 liii. Inferior Oolite. Yorkshire. 



Conifers. 



Ornioxylon, Dawson, Proc. Roy. Soc, May, 1870. 

 Palaopitys Millerii, M'Nab, Trans. Bot. Soc. Edin. vol. x. p. 312. 

 Spondylostrobus Smythii, Von Muell. Geol. Mag. Vol. VII. p. 390. Post- 

 Tertiary. Haddon, near Smythesdale, Victoria. 



Angiospermous Dicotyledons. 



Nicolia Mg)>piaca, Endl. Geol. Mag. Vol. VII. p. 309, PI. xiv. Fig. I and 2. 



Tertiary. Desert of Suez, east from Cairo. 

 N. Owenii, Carr. Geol. Mag. Vol. VII. p. 310, PI. XIV. Fig. 3 and 4. Tertiary. 

 Desert of Suez, east from Cairo. 



laE^v-iiE'V^s. 



I. — Metallography as a separate Science, or the Student's 

 Handbook of Metals, consisting of Notes of Fifty-five 

 Metals. By Thomas Allen Blyth, M.A., Ph. D., etc. London : 

 8vo. pp. 128. (Longmans, Green, Eeader, & Dyer, 1871.) 



THIS small treatise appears to consist of contributions which had 

 previously appeared in various Magazines, to some extent 

 revised by the author, and is now reprinted in a separate form. 



The design of the work is a useful one, and is intended to convey 

 in an elementary manner the general character, properties, and uses 

 of the various metals. It consists of 58 chapters, each of which, 

 except the first three, are devoted to one of the Metals, arranged 

 in alphabetical order. The first three chapters are devoted to the 

 general physical characters and properties of the various metals, 

 which, we think, might have been somewhat more extended to the 

 benefit of the reader, inasmuch as when treating of mettallic lustre, 

 specific gravity, fusibility, or crystallization, the author does not 

 mention the different kinds of lustre, or the mode of taking their 

 specific gravity, the various degrees of hardness, their relative 

 degrees of fusibility, or the crystalline forms which many of the 

 metals are known to assume.^ Nor does he distinctly enumerate all 

 those metals which are found in a native state from others which 

 occur merely in combination. And further, the author does not 

 give a complete list either of the native metals or of all the other 

 elements with which they are found associated in nature. Even 

 amongst those that are mentioned as the most general combinations 

 are oxygen and sulphur, as well as carbon and phosphorus : the two 

 former, either as oxides or sulphides, are very abundant in the 



1 In chapter 3, a brief account is given of the alloyi of metals and their general 

 characters as to their density and fusibility. 



