Continuous Growth of Wheat for Forty Years. 23 



were each divided into two, though in most cases the two 

 (a and b) were similarly manured, thus providing duplicate 

 experiments with the same manure. 



INFLUENCE OF SEASON ON THE WHEAT CROP. 



In a series of forty tables are summarised the results of 

 each season, every table showing for each plot the total 

 weight of grain, and of straw and chaff, per acre, the number 

 of bushels of dressed grain per acre, and the weight per 

 bushel. In the first report the authors observe that no idea 

 is more fixed and prevalent in the farmer's mind than that, 

 after all his labour and money have been expended, he is still 

 at the mercy of the seasons for his reward. The tables to 

 which reference has just been made supply interesting 

 evidence on this point, but the extent of the dependence upon 

 season will be made more strikingly manifest by placing side 

 by side the results obtained by one and the same description 

 and amount of manure, in the least favourable and in the 

 most favourable of the seasons during which the same manure 

 has been supplied year after year on the same land. Of the 

 twelve seasons during which, in the first twenty years, 

 uniformity of manuring was maintained, the harvest of 1863 

 gave the best results, and that of 1853 the worst, and the 

 authors compare these results in a table. Taking, however, 

 the results also of the subsequent twenty years, whilst 1863 

 still occupies the best position, 1879 achieves the unpleasant 

 notoriety of securing the worst, and it must suffice, therefore, 

 to compare in Table I. the yields in these two years. The 

 following are the numbers of the plots compared, with the 

 description of manure per acre each received : 

 Plot. 



3. Unmanured. 



2.. Farmyard manure. 



5. Mixed mineral manure alone. 



6. Mixed mineral manure and 2001b. ammonia-salts (= 431b. nitrogen). 



