Dec. I, 1887] 



NATURE 



lOI 



doubtless by oversight : it is stated that nitrate of soda 

 used as a top-dressing for mowing-fields that contain true 

 grasses "favours the growth of clover rather than of 

 grass." The reverse of this is the truth. There is a good 

 chapter on irrigation, in which it is pointed out' that, "in 

 spite of all that has been done of late years in California 

 and the adjacent regions, it is still probably true that no 

 other subject relating to agriculture so much needs to be 

 attended to by the American people as this matter of water- 

 ing the land." The questions of the disposal of excreta and 

 of sewage are dealt with in their chemical aspects. Perhaps 

 hardly due credit is given to the latest improvements in 

 some precipitation processes for clarifying sewage, but we 

 are glad to see that the author fully realizes that the sewage 

 subject is essentially a sanitary and not an agricultural 

 question. He also exposes some economic fallacies as to 

 the value of sewage by citing various instances in which 

 valuable matters are found at our doors so diluted as not to 

 be worth the cost of collecting or saving. One illustration 

 is the presence of gold in the clay of Philadelphia— i of 

 gold in about \\ million of clay. If the gold from the 

 bricks of the houses could be brought to the surface in 

 the form of gold-leaf, on each brick would be a golden 

 surface of 2 square inches. In the clay beneath the 

 portion of the city already built over is 126 million 

 dollars' worth of gold, yet no one dreams of extracting it. 

 So, except under very favourable conditions for the 

 sewage, valuable manures may be obtained more cheaply 

 than from sewage. 



The necessity for the selection of ripe, as well as pure, 

 seeds for sowing, and especially on poor soils, is insisted 

 on and illustrated by records of experiments. The great 

 importance, whether for good or evil, of micro-organisms 

 to the farmer, is often pointed out ; and the writer dis- 

 cusses the question of the sources of nitrogen available 

 for plants, and the very important question as to the 

 fixation of free nitrogen from the air by humus or by 

 clay soils. The conclusions of Berthelot, Armsby, 

 Deh^rain, and others are stated, and the author regards 

 it as proven, in the light of existing knowledge, that 

 some nitrogen from the air is really fixed as an incident 

 to certain fermentations which occur in the soil. This 

 much debated and debatable point, which is of the 

 utmost economic importance, still requires further eluci- 

 dation ; and we may hope that some further light will be 

 thrown on it by the researches of Sydney Vines on the 

 nutrition of the common bean. 



The general nature of the changes brought about in 

 the character of farming by railways and steamships, and 

 the conditions which lead to " high " or to " low " farming, 

 are discussed. An observation of Washington in a letter 

 to Arthur Young is worth recording, in this connexion : 

 " An English farmer must have a very indifferent opinion 

 of our American soil when he hears that an acre of it 

 produces no more than eight to ten bushels of wheat ; 

 but he must not forget that in all countries where land is 

 cheap and labour is dear the people prefer cultivating 

 much to cultivating well." 



Special chapters are given to barley and oats, and 

 there are three chapters on pastures, grass, and hay, 

 mainly from a New England point of view. In one of 

 these chapters it is stated that the East Anglian word 

 " rowen " for " aftermath," used by old writers, but now, 



we believe, confined to parts of Suffolk, is in common 

 use in New England. 



One minor defect, which might have been remedied by 

 an editor of the English edition, is the use throughout 

 the book of many different systems of weights and mea- 

 sures, e.g^. the long (English) ton of 2240 pounds, the 

 short (American) ton of 2000 pounds, pounds and bushels 

 per acre as well as kilogrammes per hectare, and German 

 pounds per morgen, per Saxon acre, and per Hessian 

 acre, and even quintals per acre. A reduction of these 

 to one system would have rendered the results more com- 

 prehensible, and comparisons easier. Also, a few of the 

 chemical names are not those now in use in this country, 

 and the use of the terms bi-phosphate of lime and di-calcic 

 phosphate as synonymous is very misleading. 



For the sake of the British farmer, who is not such a 

 reading man as his American confrere, we could wish 

 that some of the subjects had been rather more digested, 

 and that more illustrations had been drawn from English 

 sources, but thanks are due to Mr. Storer for a very sugges- 

 tive work, that can be confidently recommended to those 

 interested in agriculture for perusal and careful study 

 during the long winter evenings. It cannot fail to 

 awaken a more intelligent interest in the physics and 

 chemistry of the farm. Moreover, notwithstanding the 

 author's modesty, it will be found very useful to the 

 student of agricultural chemistry. 



WE A THER. 



Weather : a Popular Exposition of the Nature of 

 Weather Changes from Day to Day. By the Hon. 

 Ralph Abercromby. (London : Kegan Paul, Trench, 

 and Co., " International Scientific Series," 1887.) 



THE author of this book has undertaken a task the 

 difficulty of which has deterred all previous writers, 

 for FitzRoy's "Weather Book" can hardly be termed 

 a text-book of the subject, and, moreover, it was written 

 at a date at which weather telegraphy was in its infancy. 

 The books which have appeared during the last two 

 decades have been either manuals mainly for the use ot 

 seamen, like the Barometer Manuals of the Meteorological 

 Office ; or explanations of the interpretation of weather 

 charts, like Mr. Scott's " Weather Charts and Storm 

 Warnings," of which the third edition was lately noticed 

 in these pages. The idea of telling an isolated observer 

 how to employ local weather signs and the manifold modi- 

 fications of clouds in aiding his own judgment of local 

 weather has not hitherto been adequately carried out. 



Mr. Abercromby is peculiarly well qualified for the 

 task of preparing a weather text-book, for not only is he 

 gifted with an unusual faculty of observing weather phe- 

 nomena, and especially clouds and their changes in this 

 country, as is proved by the papers he has read on various 

 occasions ; but he has had more leisure to travel to 

 " foreign parts " than falls to the lot of most meteorologists- 

 The book relates to weather in general, as distinguished 

 from storms, and not merely to the weather of the British 

 Isles ; for, though the latter subject occupies most of the 

 work, the information given as to the weather over more 

 extensive areas, such as those of the North Atlantic and 

 the United States, is most instructive and valuable. The 



