18 



taken. A given weight of each is partially dried for 

 preservation, for nitrogen determinations, or for other 

 organic examination ; and duplicate portions are dried 

 at 100, the dry matter determined and recorded, and 

 then the duplicate portions are burnt to ash, the amounts 

 of ash recorded, and the ashes preserved. 



There are practically no duplicate plots; so that, 

 so long as the experiments are continued, there 

 should be very little reduction, either in the separate 

 harvesting, or the separate sampling. After the 40th 

 crop, however, it may be considered whether crop- 

 samples need still be taken from the produce of plots 

 IN, 2N, 50, 5A, M, and 6-2, or whether in the case 

 of some of these the sampling might not be dis- 

 continued. Samples should certainly still be taken 

 from the grain, and from the straw, of Plots 6-1, 7-1, 

 7-2, and the other 20 plots. The utmost reduction in 

 sampling that can be suggested is, therefore, from 29 of 

 grain and 29 of straw, as at present, to 23 of each after 

 the 40th crop. 



Fewer determinations of nitrogen have been made in 

 the grain and straw of barley than in those of wheat, 

 and most of those which have been made are in "mixed- 

 plot" or "mixed-year" samples; that is on mixtures 

 made proportionally to the amount of produce in each 

 case, from several plots in one year, or from one plot 

 over several years. The results on the "mixed-plot" 

 samples were published in No. 11 as before referred 

 to, but those on the " mixed-year " samples have not yet 

 been published, and will probably be reserved until 

 the results of the complete ash-analyses are given in 

 detail. 



Complete ash-analyses have been made in the case of 

 44 grain and 44 straw ashes, selected for the illustration 

 of the influence of exhaustion, manuring, and variations 

 of season, on the mineral composition of the crop ; those- 

 illustrating the influence of season, being from the 

 produce of individual or mixed plots, in individual 

 years, and those illustrating that of exhaustion and 

 manuring being from "mixed-year" samples, covering 



