NATURE 



24 



IIIRSDAY, MAY 30, igrS. 



GARDENING: OLD AND NEW. 

 The Standard Cyclopedia of Horticulture. By 

 L. H. Bailey. In six volumes. Vol. v.,.P-R. 

 Pp. v + 2423-3041 + plates. Vol. vi., S-Z and 

 Supplement. Pp. v + 3043 -3639+ plates 

 York: The Alacmill.-in ("o. ; London 

 and Co., Ltd., kiM' i /. ) Price 25 

 vol. 



(New 

 Macmillan 

 net each 



of 



THE.excellence of I'n.r. Hnilrv's " Cv, lopcdi; 

 Horticulture," the L-arlier xoluiiics ol wiiich 

 have already been noticed in these pages, is main- 

 tained in the fifth and sixth volumes, which have 

 now appeared and arrived safely in this country. 

 We can imagine no more interesting or stimulat- 

 ing reading for British horticulturists than the 

 articles on subjects grown by them and also culti- 

 vated in America. 



The differences of climate between the States 

 ^d this country are reflected in the different horti- 

 cultural treatment practised by European and 

 American experts. Thus, in the case of the straw- 

 berry we find that in the southern districts of the 

 United States it is the practice to take one crop 

 only and then to discard the plants, whereas in 

 our more moderate climate growers generally take 

 three crops before ploughing up their plantation. 



Again, as is to be expected in the case of so 

 American a genus, the grap>e-bearing species of 

 Vitis are treated of in a far more comprehensive 

 manner than in any British cyclopaedia; indeed, 

 we confess to a glad surprise to learn that there 

 are no fewer than thirty-six species of Vitis which 

 bear edible grapes. 



Here and there the British horticulturist will 

 notice omissions, as, for example, the failure of 

 the author responsible for the article on tulips to 

 cite among the "literature" the admirable mono- 

 graph of Mr. Dykes on that genus of plants. 



The rapidly. growing importance of California as 

 a seed-raising country is strikingly illustrated by 

 the statement in the article "Seed and Seedage " 

 that the seeding acreage under lettuce, onion, and 

 sweet-pea — most popular of flowers in America — 

 is no less than 5000. In addition to these seed 

 crops, America contributes large and increasing 

 quantities of seed of the culinary pea, bean, cab- 

 bage, radish, and others ; nevertheless, the 

 American imports of garden seed alone are of , the 

 annual value of two million dollars. 



Among the important genera described in these 

 volumes are Primula, Prunus, Pyrus, Rosa, and 

 Solanum, and each is dealt with in a thorough 

 manner. It is noteworthy that, as admitted in the 

 article on the potato, America, like ourselves, has 

 awakened late to the great importance of this 

 crop ; Germany alone of all the great nations 

 seems to hav-c taken advantage of the fact that 

 this plant is the most productive of all cultivated 

 food plants. Whereas half .the huge crop 

 raised in Germany is used for food for stock or 

 foi commercial purposes, only i per cent, of the 

 far smaller crop is similarly employed in America. 

 NO. 2535, VOL. lOl] 



The treatment of Priumhi si)ic)isis — that queen 

 of flowers for glass-house luitivation — is too 

 meagre to satisfy the British florist, and none of 

 the chief varieties — so interesting both scientifically 

 and floristically — is mentioned. Nor do we think 

 that Prbf. Bailey would concur in the statement 

 with respect to peas (p. 2490) : " Left to them- 

 selves, the varieties of peas soon lose their char- 

 acteristics through variation." 



Broadly speaking, however, the information 

 piovided in the cyclopaedia is accurate and com- 

 prehensive, and we advise all British horticul- 

 turists to provide themselves with a copy. Once 

 they possess it, it will be in constant use. 



PRINCrPLES AND METHODS OF SCIENCE 



TEACHING. 

 A Text-book in the Principles of Science Teaching. 

 By Prof. G. R. Twiss. Pp. xxvi + 486. (New 

 York : The Macmillan Co. ; London : Macmil- 

 lan and Co., Ltd., 1917.) Price '^s. 6d. net. 

 THIS book is a treatise on the principles and 

 methods of science teaching in secondary 

 schools, and is intended to serve as a text-book on 

 education in training colleges and as a guide to all 

 who are concerned with science teaching and its 

 organisation. It is a large book of twenty-four 

 compact- chapters, each being a veritable mine of 

 information. At the end of each chapter there are 

 valuable lists of. reference books and sets of ques- 

 tions for further study, and in the appendices are 

 given a selected list of science books suitable for 

 school libraries, a bibliography for teachers, and a 

 list of scientific periodicals. 



In the earlier chapters are set forth the prin- 

 ciples which should underlie all science teaching, 

 the meaning of science, the viewpoint of the 



I science teacher, and the educational value of 

 science in discipline and culture. The rest of the 



i book is devoted to the details, of the methods of 

 class-teaching in biology, geography, physics, 

 chemistry, and what is known as "general 



I science," and to an elaboration of ilie design of 



' classrooms and laboratories, \\ ilh (-atalogues of 

 furniture, apparatus, and plant. 



In his earlier chapters the author emphasises 

 the principles which he holds should form the 

 basis of science teaching. He tells us truly — and 

 it is a fact which, strangely enough, stands more 

 in need of emphasis to-day than at any other time-— 

 that "modem science and modern social and in- 

 dustrial life are inseparably linked together, and 

 that each in turn causes the other to advance." 

 There is nothing new in this principle, but its 

 application to education in schools is being re- 

 jected, one after another, by educational boards 

 and Government committees the function of which 

 it is to reconstruct education after the war. In 

 Anieric a. apparently, the authorities put their faith 

 in the principle. "The science work of the 

 school," says our author, "must be kept in close 

 touch with the doings of everyday life, and especi- 

 ally witti the activities that lie nearest to the im- 

 mediate interests of the boys and girts." This, 

 \v<- believe, is the true dem(X"ratic principle of edu- 



