BARLEY. 93 



be supposed, however, that the whole of these plus amounts 

 were surplusage ; for although the average yield of grain has 

 been to such a great extent maintained, the character of the 

 plant has obviously depreciated for a good many years, and 

 several times in recent seasons even the yield of grain has 

 been considerably deficient. Indeed it would seem that the 

 plant has become more and more sensitive to adverse con- 

 ditions of soil and season. 



Turning now to the soda, it is seen that, whether we look Soda in the 

 at its percentage in the ash of the grain and of the straw, its crop ' 

 proportion in 1000 dry substance, or the amounts in the 

 acreage crops, very much more was found in the crops grown 

 without its supply, but where potash was deficient, than 

 where soda was itself annually supplied. This is strikingly 

 illustrated by reference to the average amounts per acre per 

 annum in the total crops, grain and straw together. Thus 

 the average amounts of soda in the total crop were — over the 

 first period, without any supply of either potash, soda, or 

 magnesia, 8.4 lb., and with the supply of all three, only 3.8 

 lb.; over the second period, without the supply 15.2 lb., and 

 with it only 3.7 lb. ; over the third period, without the 

 supply 11.8 lb., and with it only 2.7 lb.; over the fourth 

 period, without the supply 10.7 lb., and with it only 2.2 lb. ; 

 and lastly, over the forty years, without supply of either 

 potash, soda, or magnesia, 11.5 lb. of soda, and with the 

 supply of all three, only 3.1 lb. of soda per acre per annum. 



Thus, then, not only was there much more soda taken up 

 or retained by the plant where it was not supplied than 

 where it was, but it is evident that there was the more soda 

 taken up the less the supply of potash. The amounts of soda 

 retained in the grain are, however, seen to be but small ; 

 there was more, it is true, where there was a deficiency of 

 potash, and where more soda was taken up. But looking to 

 the amounts of soda per cent in the grain-ash, or per 1000 

 dry substance of the grain, it would seem probable that the 

 larger amounts where there was a deficiency of potash, and 

 more total soda taken up, were only due to larger amounts 

 eliminated from the grain proper, and retained in the adher- 

 ent palece, or chaff. Whether, however, the soda has been of 

 any avail in the earlier or merely vegetative stages of growth, 

 as a carrier, or otherwise, may be a question. 



Next as to the phosphoric add, of which there was the same Phosphoric 

 annual supply on both plots. It is seen that, whether we ^r m the 

 take its percentage in the ash, its proportion to the dry sub- 

 stance, or its average quantity per acre, the amounts are, in 

 the comparable cases, comparatively uniform ; the differences 

 not being greater than can be supposed to be connected with 



