570 Revieios — Giirney^s Manual of Crystallography. 



the estimated acreage of property. This county has long been 

 considered a classical field to the geologist, as it presents some of 

 the finest examples of geological phenomena, whether as connected 

 with igneous or stratified rocks, or with physical and palseontological 

 geology. The main formations of Mid-Lothian are Palaeozoic, from 

 the Silurian to the Carboniferous, with the associated igneous rocks, 

 over which is irregularly spread a more or less deep covering of 

 glacial or boulder clay. 



The county of Edinburgh in regard to its agriculture takes a 

 high position. Not only have her farmers brought this science to a 

 standard of perfection rarely attained, but the agricultural produce 

 and value of land in the better portions of the county are ex- 

 ceptionally good. The relative value of the land is clearly shown 

 by means of colours on the agricultural map of the county accom- 

 panying this paper, and which is based on « Prof. A. Delesse's 

 " Carte Agricole de la France " noticed in this Magazine (Dec. II. 

 Vol. IV. p. 474). The annual rentals are given under nine divisions, 

 ranging from £1 to £20 and £40 per acre, these being dependent on 

 the nature of the soil and the favourable position of the farms, those 

 near the metropolis being the most highly rented. The meteorology 

 is simply considered with regard to the temperature, rainfall, and 

 altitude, these being the three main meteorological topics of agri- 

 cultural interest. This essay is certain to prove of value to those 

 interested in the district. 



V. — Manuals of Elementary Science. Ckystallography. By 

 Henry Palin Gurney, M.A. Fcap. 8vo. pp. 128, with 46 

 woodcuts. Is. (London, 1878 : Society for Promoting Christian 

 Knowledge.) 



THE systematic study of scientific Crystallography has certainly 

 but few admirers, in this country at least. " Its great impoi't- 

 ance to the chemist, the physicist, and the geologist cannot," as the 

 author of the work which we are now noticing truly says in his 

 preface, " be questioned." The fact is, that the subject is beset with 

 mathematical abstruseness, and has been hitherto without suitable 

 introductory manuals. Many students have consequently been 

 driven to empirical systems, which are little better than the learning 

 by rote of a number of geometrical forms. We have met with 

 many other students whose knowledge of minerals is that only of 

 the chemist, or even of the miner. The object of the present little 

 work is to introduce the subject scientifically to the non-mathe- 

 matical. We are at a loss to know for whom such works as the 

 present, and Professor Clerk Maxwell's Matter and Motion, in the 

 same series, are designed by their publishers; since surely the some- 

 what advanced students in special lines of scientific research, who 

 alone can appreciate them, would gladly pay double or treble their 

 price and possess the author's ideas lucidly expressed in unconfined 

 space. These manuals, however, certainly contain a vast amount of 

 useful matter. The two main points of merit in Mr. Grurney's book 

 are, first, the clear, unmathematical text, supplemented by some 



