92 SCIENCE AND FRUIT GROWING 



section, it is not significant, for it was found that, if the returns 

 for one exceptional year (1915) were omitted, this favourable 

 balance would be converted into an adverse one of 16 per cent. 



*. 



Plot A. No manure . . . . . 39 16 = 100 



Dung, 30 tons . . . 24 9 = 61 



Artificials equal to 30 tons dung . 32 14 = 8.3 



Plot B. Artificials and 10 tons dung . . 41 b = 100 



Artificials and 30 tons dung . . 45 = 10} 



With such a general absence of all effects from manure, 1 it was 

 useless to examine the details of those experiments wherein the 

 nature of the manure was varied by leaving out one or other 

 of its constituents. Only in one case were results obtained 

 which appeared, though doubtfully so, to lead to some positive 

 conclusion : that was in the case where nitrate of soda was applied 

 in the summer, instead of in the spring, the weight of the crops 

 and the size of the fruits being thereby notably increased. But 

 there were reasons for questioning these results (XVI, 21). In 

 the same way, extra coloration of the fruit was observed in the 

 case of a plot dressed with iron sulphate at the rate of 2" 8 grams 

 per square metre, but only in one season out of the twenty- two. 

 No such extra coloration was noticed in a corresponding plot 

 dressed with manganese sulphate. 



FARM CROPS AT RIDGMONT (XVI, 25) 



That the almost entire absence of effect of manures on fruit 

 trees at Ridgmont was due to any exceptional richness of the soil 

 there, was prima facie improbable, for, according to the analysis 

 of it (p. 84), it would be classed as a soil of not more than average 

 fertility. 



To place the matter beyond doubt, however, certain farm crops 

 were grown in the very plots formerly occupied by trees, after 

 some of these had been removed. As a result of five years' trials 

 with onions and potatoes, the following values were obtained 



Weight of crops 



Size .... 



1 Similar results have been obtained in America. U. P. Hedrick, New 

 York State Agric. Expt. Sta., Bull., 339, 1911. C. D. Woods, Maine Agric. 

 Expt. Sta., Bull., 236, 1915, pp. 52-3. 



