Oil the Growth of Barley ly different Manures, ^c. ^ 52 1 



These nitrogen determinations, which, counting the duplicates 

 made on each specimen, amount to nearly 100, were all con- 

 ducted in the Rothamsted laboratory, by Mr. John Masters ; 

 excepting that here and there repetitions have been made by 

 Dr. Pugh or Mr. F. A. Manning for the purpose of confirmation. 

 It may be added, that the process adopted was that by burning 

 with soda lime, and estimating by the so-called " titrir " or 

 volumetric method. 



At the moment we are writing, the whole of the analyses 

 which our plan should include are not completed, and we fear 

 that the Tables will eyen eventually show some blanks. Not- 

 withstanding these, we shall still have the means of illustrating 

 incidentally, by a very extensive series of comparative results, tlie 

 influence of season and manuring on the jyercentage of nitrogen 

 in the barley crop. And, so far as the more special object of 

 inquiry is concerned — namely, that of the relation of the nitrogen 

 in the increase of produce to that in the manure employed — we 

 shall be enabled to provide for six consecutive seasons, and for 

 some of them for several different characteristic conditions of 

 manuring, the important data of — 



1st. The amount of nitrogen per acre in the corn, the straw, 

 and the total produce. 



2nd. The increase in the amount of nitrogen yielded per acre 

 (in corn, in straw, and in total produce), by the use of given 

 nitrogenous manures. 



3rd. The proportions respectively, of the nitrogen recovered, and 

 not recovered, in the increase, to a given amount (100 parts) 

 supplied in manure. 



The percentage and acreage results are given in Tables XVI., 

 XVII., and XVIII. respectively, as follows: — 



In Table XVI. the mean percentages of dry matter, and the 

 victual determinations of nitrogen (and their mean) in the dry 

 matter, of both the corn and straw, of the different mixed samples 

 described above. By the side of these points of composition, are 

 given some particulars of the quantity and quality of the produce 

 analysed, for the study of the connection between them. 



In Table XVII. similar particulars are given; excepting that 

 here the percentages of nitrogen are calculated upon the corn 

 and straw in their natural state of hydration. The percentages 

 of nitrogen in this Table are therefore applicable to the produce 

 as harvested. 



Table XVIII. gives, besides the acreage amounts of the 

 produce itself, the acreage amounts of nitrogen in the actual 

 produce ; the amounts in the actual increase ; and finally, the pro- 

 portions respectively, 7'ecovered, and not recovered, in the increase, 

 lor every 100 parts supplied in manure. 



