128 



Can the superiority he ascertained by the mere inspection ot 

 the grains ? Again, no. Does it depend upon its superior specific 

 <'ravity ? Here, I think, tlie true solution would be found if only 

 we could accurately determine the relative specific gravity of two 

 <'rains (very nearly alike) icithout destroying their powers of rjermin- 

 ■(diou, for it is evident that it would be of no avail to discover the 

 supposed best grain if by discovering wo destroyed it, and thus 

 prevented our proving by actual growth that it was indeed the 

 best as supposed. But in fact we cannot at present determine by 

 any known process the relative specific gravity of two grains of 

 wheat without destroying their germinating power. Le Couteuv, 

 pa^e 41, says " It will be recollected tliat, in order to ascertain 

 the relative specific graA-ity of each variety of corn, the number of 

 "rains were noted that exactly weighed a scruple." But of 

 course, tliis is not specific gravity. I have roughly tried solutions 

 of diff"erent densities in order to divide a number of grains into 

 a rough classification of their specific gravities, and by actual 

 wrowth to see whether this held good, but without any distinct 

 result. The fact is, I believe, that the oily nature of the cover- 

 in"' of the grain prevents accurate and al)solute contact, and that 

 thus the accurate measurement of specific gravity by displacement 

 becomes practically of no value, for it must be borne in mind 

 that the difference between any two grains must he excessively 

 minute. My belief is, and has long been, that the specific gravity 

 of a grain depends upon, or is at least concurrent with, the 

 amount of gluten it contains ; that the grain containing the most 

 gluten possesses the greatest power of supporting animal life, and 

 that this power is identical with that of vegetalde growtli. 



Leaving, hoAvever, the domain of speculation I will now turn 

 to that of practical experiment and its teaching. Before a 

 Society like your owa, I Avill not treat the subject simply in its 

 agricultural aspect, but first endeavour to indicate how, step by 

 step, I was led up to the discovery of the law governing cereal 

 growth. Here I may, perhaps, be allowed to explain how it was 

 -that I came to take any interest in the matter. I had suffered 



