534 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
to industrial use, even when those discoveries have in the end far-reaching results. 
Too often, the thinly- veiled feeling of contempt or pity which is felt by the 
" practical " man towards one whom he thinks stalks through life with his head in 
the clouds or buried in his apparatus is shared by the " pure science " man — 
though not often by those at the head of their line on either side- — and until each is 
willing to accept the help of the other the utilization of scientific discoveries for 
the betterment of the human race and for the increase of industrial prosperity 
cannot be realized to the fullest extent. The essays in this book should do not 
a little to bring about that desirable rapprochement. 
Like all the publications which emanate from the Cambridge University 
Press this lacks nothing in make up, type and paper being excellent in every 
way, and the occurrence of so objectionable a form as " preventative " on p. 291 
therefore surprises us the more. 
" Productive Plant Husbandry." By K. C. Davis. 8vo., xvi -f- 462 pp. 
(Lippincott, London.) ys. 6d. net. 
Judging by the number of books published dealing with agricultural and 
horticultural instruction in school and colleges, America has realized the im- 
portance of systematic teaching in rural subjects in a way that is unknown in 
England. It may well be that agriculture may be taught in such a way as to 
be quite useless to the pupil either as a training for the mind or for the practical 
treatment of soil and crops, on the other hand a carefully planned course of 
science and practice may be as educational as any subject of the schools and of 
the greatest practical value. 
The present volume deals with the growth and utilization of plants, and 
illustrates in an excellent fashion the kind of course likely to be useful. 
The book would not be entirely suitable for the English student, for the 
material used for illustration, common in America, is not always to be had here, 
but for the teacher the whole volume is replete with suggestion and much of 
the actual work proposed could be used with advantage in courses here. We 
have great pleasure in recommending the book to all teachers who wish to give 
a rural bias to their work, and to all students who are seeking a plain statement 
of the methods of plant production and the reasons for them. 
" How to Collect and Dry Flowering Plants and Ferns." By H. S. Thompson, 
F.L.S. 56 pp. 8vo. (Routledge, London, 191 7.) Paper covers, yd. net. 
One is often asked for a book giving directions for the preservation of plants 
for future study. Such directions are often printed, mainly as part of larger 
volumes ; but we have here a handy little book containing all the information 
likely to be required, and written by one with a long experience of his subject. 
We can very heartily recommend it to all students and others who seek for in- 
formation and plain readable directions upon the subject dealt with. 
" Manuring for Higher Crop Production." By E. J. Russell, D.Sc, F.R.S 
Ed. 2. viii -f 94 pp. 8vo. (University Press, Cambridge, 1917.) 3s. 6d. net 
"Soil Conditions and Plant Growth." By E. J. Russell, D.Sc, F.R.S 
Ed. 3. viii -f 243 pp. 8vo. (Longmans, Green, London, 191 7.) 5s. net. 
So short a time has elapsed since the first edition of the first of these capital 
books was published and reviewed in this Journal that we need only draw atten- 
tion to the new edition. Additions mainly dealing with the breaking up of 
grass land have been made, and the whole forms a very useful guide to the treat- 
ment of land for farm crops. 
A third edition of the second volume also calls for little remark except that 
it, too, contains several alterations in the text, and is brought up to date by 
the inclusion of a chapter on colloids so far as the soil is concerned with them. 
The book is essentially a monograph on the soil, and a review of the present 
position of soil science. 
" Grow Your Own Vegetables." By S. C. Johnson. 199 pp. 8vo. (Ujawin, 
London, 1918.) 6s. net. 
In these days when allotments have sprung up in such vast numbers every- 
where, and are likely still to extend in all parts of the kingdom, this is a most 
welcome book, as there are so many problems that puzzle the allotment holder 
that he will be glad to have the advice so fully afforded and so clearly explained. 
The numerous diagrams are a great aid, and will be much appreciated. It is 
a book we can confidently recommend. 
