394 CHEMICAL DISCOVERY AND INVENTION 



wheat supply it may be said that whilst wheat is capable of 

 producing very large crops under favourable conditions as to 

 soil, climate and manuring, it possesses a remarkable power of 

 obtaining food from a poor soil. It can stand a considerable 

 amount of frost, and it can thrive over an immense area of the 

 world's surface. Although endorsing all that Sir William 

 Crookes says as to the importance of wheat as a food, we cannot 

 adopt his desponding views in regard to the future supplies of it. 

 That we may have considerable fluctuations in produce and in 

 price, the result of war, or of the vicissitudes of the seasons in 

 different countries, is very probable ; but we believe that there 

 will always be a sufficient supply forthcoming, for those who 

 will find the money to purchase it at a remunerative price." 



To this assurance from so respectable an authority may be 

 added a few considerations arising out of the progress which has 

 been made by agriculture in the years which have elapsed since 

 their words were written. The production of wheat for the 

 whole world has increased very largely for several reasons. 



Wheat is now grown over large areas not counted on in 1898, 

 including Australia, India, Egypt, South America, while it has 

 increased enormously in Canada and considerably in the Russian 

 Empire and the United States. 



Wheat breeders have also succeeded in raising varieties more 

 suitable to local conditions than the older sorts, and therefore in 

 improving yields, while better rotations and more manure are 

 now used than formerly. 



Crookes' remedy for shortness of wheat supply was the pro- 

 duction and application to the land of much larger amounts of 

 nitrogen in the form of nitrate. In reviewing the world's annual 

 wheat crop, and the known results of applying nitrate of soda 

 to the experimental plots at Rothamsted, he calculated that to 

 raise the 12-7 bushels per acre, which was the average yield of 

 wheat of the world's crop, to 20 bushels, it would require 12 

 million tons of nitrate annually to be distributed in varying 

 amounts over the wheat-growing countries of the world, in 

 addition to the 1 J million tons already absorbed by various crops. 

 But though Lawes and Gilbert would regard a cheap and liberal 

 supply of nitrate as a very great boon to the agricultural world, 

 they thought it very doubtful whether an average of 20 bushels 

 per acre would be obtained year after year the world over by 

 the annual application of 12 million tons of nitrate. They 



