February, 1910i] 



90 



The chapter on farmyard manure is 

 eminently practical and useful, and 

 recent work on such subjects as root 

 excretions, effect of fertilisers on tilth, 

 and on residual values of manures, 

 brings the book well up to date. It is 

 sought to distinguish between manures 

 and fertilisers, the former designating 

 more or less complete plant foods, the 

 latter those materials which supply one 

 element in the plant food, nitrogen, 

 potash, or phosphoric acid. The per- 

 version of the meaning of the word 

 manure from its original significance, 

 hand work, is no less curious than the 

 use of the word tillage to mean artificial 

 manures, which use still persists in the 

 eastern midlands. The part of the work 

 relating to lime is worthy of serious 

 attention from all agriculturists, as it is 

 probable that the lack of carbonate of 

 lime in a soil is more often than any 

 other cause an explanation of the com- 

 parative infertility or absence of satis- 

 factory results from manuring. A 

 chapter on the valuation and purchase 

 of fertilisers puts this important method 

 of calculation simply and accurately, 



and a concise statement of the Ferti- 

 lisers and Feeding Stuffs Act will be 

 useful to all users of manures. 



Mr. Hall's remarks on the soil-inocula- 

 tion question supplement and strengthen 

 the advice he gave in his work on the 

 soil, and the experiments on the new 

 nitrogenous fertilisers, cyanamide and 

 nitrate of lime, show the values of these 

 fertilisers in terms of their competitors, 

 nitrate of soda and sulphate of ammonia. 

 The Rothamsted experiments are, of 

 course, freely drawn upon to provide 

 data, and in the hands of the present 

 director of that station these results are 

 being endowed with fresh life and 

 excellently practical applications. The 

 tables of results are concise and well 

 arranged, so that the reader is not faced 

 with an immense array of figures and 

 tables, and bewildered without being 

 enlightened. To sum up, this is a sound 

 and scientific book which should be in 

 the hands of every practical agricul- 

 turist as well as in those of the student, 

 the teacher, and the manufacturer. 



M. J. R. D. 



GUMS, RESINS, SAPS AND EXUDATIONS. 



WHAT HELPS TO KEEP RUBBER 

 DEAR. 



(From the India Rubber World, Vol. 

 XLI., No. 2, November 1, 1909.) 



No doubt it would seem reasonable to 

 many minds, if not absolutely certain, 

 that a heavy advance in rubber prices 

 could not fail within a short period to 

 lead to a corresponding increase in the 

 output of rubber. This is the general 

 commercial rule, and consumers of 

 rubber seem generally disposed to apply 

 it to rubber production. In view of 

 present price conditions, however, it 

 may be worth while to consider how the 

 bringing of rubber to market differs 

 from dealing in most other commodities. 

 In the first place, however well syste- 

 matized the production of rubber may 

 be in portions of the Amazon valley, 

 this condition does not extend to the 

 whole region, and whatever improve- 

 ment may be attempted, progress is 

 necessarily slow, if for no other reason 

 than the scarcity of population suitable 

 for gathering rubber. 



A large percentage of the rubber 

 gatherers in Brazil to-day remain on the 

 ground temporarily, so that each season 

 a fresh immigration is necessary, very 



much as if the city of San Francisco 

 should plan to lay new pavements six 

 months in every year, and for each new 

 piece of work should send to Italy for 

 labourers, with the idea that most of 

 them would return home after the work 

 was finished. The rubber which is 

 coming into Para to-day is being got out 

 by seringueiros who were employed as 

 long ago, perhaps, as January last, and 

 most of the rubber to come out during 

 the present cutting season will be the 

 result of similar engagements. The fact 

 that rubber is selling at New York for 

 $1 a pound more than when rubber 

 gatherers were last employed to go up- 

 river naturally, therefore, will have 

 little effect in the way of increasing 

 this season's output. The high price 

 level can hardly have a widespread 

 effect upon the employment of rubber 

 gatherers before next January, and the 

 crop resulting from engagements made 

 then will not all reach market before 

 the summer of 1911. 



But other conditions are to be con- 

 sidered than the labour supply. There 

 is a scarcity of local capital. It is neces- 

 sary for the seringal owner, particularly 

 if far from the primary markets, to be 

 equipped with supplies for his working 

 force in advance for the whole season. 



