August 25, 1 881] 



NATURE 



379 



Leibniz amongst the worthies to whom the credit of im- 

 provements in the steam-engine is given. The one common 

 feature that runs through the many different types of 

 steam-engine is the piston working within a cyHnder. 

 No engine before Papin's time was adapted for any useful 

 purpose except for raising water, and none had a piston 

 in a cylinder. No engine since Papin's time of the 

 thousand varied types has been devoid of this feature. 

 But the very feature which Papin introduced, and on the 

 introduction of which his claim to be called the inventor 

 of the steam-engine has been founded, was, as we now 

 know, the suggestion of another mind. We owe the 

 application of the piston-principle in the steam-engine, not 

 to Papin, but to Leibniz. 



CHEMISTRY OF THE FARM 

 The Chemistry 0/ the Farm. By R. Warington, F.C.S. 

 Pp. xiii. and 128. (London : Bradbury, Agnew, and 

 Co., 1881.) 



THE chapters of this little handbook appeared origin- 

 ally in detached portions in the Agricultural Gazette. 

 They have been revised, and are now issued in a convenient 

 and compact form. A well-ordered manual of agricultural 

 chemistry, clearly written and perfectly abreast of recent 

 advances in the sciences underlying the farming art, has 

 long been wanted. So far as the limits of its size and scope 

 allow, Mr. Warington's volume fulfils our expectations. It 

 is a satisfaction which is seldom afforded us to read a 

 book on agricultural chemistry written by a true chemist 

 trained in laboratory work and versed in the progress 

 made through English and foreign researches. The 

 applications of chemistry to agriculture are manifold, and 

 cannot be grasped by chemists who do not combine with 

 their chemistry a"competent knowledge of vegetable and 

 animal physiology and'of mineralogy. Yet to learn or to 

 teach the Chemistry of the Farm without a knowledge 

 even of the foundations of chemical science is commonly 

 attempted, though it can never succeed in any true sense. 

 And we quite agree with Mr. Warington that a wider 

 range of scientific knowledge than this is needed even for 

 the student of agricultural chemistry — much more then 

 for the teacher. To talk about this applied science to 

 persons without previous scientific knowledge, and to look 

 for satisfactory results, is to expect a plant unfortunately 

 destitute of roots to blossom and bear fruit. 



We think then that Mr. Warington's handbook is valuable 

 on account not only of the knowledge with which its subject 

 is handled, but also on account of the spirit with which that 

 subject is approached. That a new work on agricultural 

 chemistry was sorely needed does not admit of question. 

 In France and in Germany the educational literature of 

 this subject includes many excellent works which have no 

 English counterparts. Johnston's treatise, full as it is of 

 valuable observations, is too thoroughly out of date in 

 method as well as in matter to admit of satisfactory 

 revision ; much the same judgment must be passed on 

 Anderson's " Agricultural Chemistry," now twenty years 

 old and out of print. Even if Georges Ville's work on 

 Manures included (which it is far from doing) anything 

 like the whole domain of the Chemistry of the Farm, it 

 is about as unsafe and misleading a book as could be put 

 into the hands of a student. Mr. Warington has given 



us, in fact, not all we want, but a good bit of it. He has 

 used, and that judiciously, both German and English 

 text-books, researches, and memoirs, and has put the main 

 facts they enounce into a neat form, so as to be " under- 

 standed of the people." The two capital text-books of 

 Emil Wolff have been laid under contribution by Mr. 

 Warington ; while the chief results of some of the match- 

 less Rothamsted Memoirs by Lawes and Gilbert have 

 been skilfully introduced into his pages. Of the contents 

 oftheseitis now perhaps time to say a few words. In 

 five chapters the growth, the food, the nutrition, and the 

 products of farm crops are discussed ; in another five, 

 animal growth, food, nutrition, and products. Of the 

 diverse origins and properties of soils but little is said ; 

 as to the utilisation of urban sewage, nothing. And we 

 should have been fglad to have found fuller accounts of 

 many subjects which are but lightly touched upon in these 

 pages. But the difficulty of treating so vast and complex 

 a subject intelligibly in so few pages makes us surprised, 

 not that some things are omitted from, but that such a large 

 number of things are included in, this little book. Some 

 facts and figures which the author w-ould doubtless have 

 liked to introduce have been kept out of his pages by the 

 absolute necessity of finding room for numbers and argu- 

 ments of primary importance. For instance, it would 

 have been unwise to have curtailed the space bestowed 

 upon the " Digestibility of Foods" and the "Albuminoid 

 Ratio. " 



In reading through this handbook carefully we have 

 been unable to discover more than a very few statements 

 which we cannot completely endorse ; in fact the majority 

 of such alterations as we would suggest would be oi form 

 rather than of substance. We cannot, however, refrain 

 from expressing our regret that the percentages of albu- 

 minoids in potatoes and roots as given in the table on 

 p. 72 should be the old erroneous figures condemned on 

 the very next page as greatly in excess of the truth. Mr. 

 Warington has however so thoroughly recognised the 

 importance of the discrimination between albuminoid and 

 non-albuminoid nitrogen that we must attribute the in- 

 clusion of the incorrect figures in his tables to the difficulty 

 of constructing a complete series of analyses comparable 

 with one another in this particular of the percentage of 

 true albuminoids. A. H. Church 



OUR BOOK SHELF 



A Handbook of the Vertebrate Fauna of Yorkshire. Being 

 a Catalogue of British Mammals, Birds, Reptiles, .Am- 

 phibians, and Fishes, showing what species are or have 

 within historical periods been found in the County. By 

 Wm. Eagle Clarke and Wm. Denison Roebuck. ' (Lon- 

 don : Reeve and Co., 1881.) 



This little volume is dedicated to the President-Elect of 

 the British .Association, and most seasonably makes its 

 appearance on the eve of the meeting of that Association 

 in the city and county of its origin, when it will celebrate 

 the completion of the first fifty years of its existence. Its 

 object is the enumeration of those animals with a verte- 

 bral column which either are or have been found in 

 Yorkshire, and the careful definition of their faunistic 

 position and geographical distribution within the county. 

 It would appear that there has never been a list of the 

 mammals, birds, or fishes of the county of York published, 

 and in this respect it presents a striking contrast with its 

 neighbouring counties of Norfolk, Northumberland, and 



