PRACTICAL VALUE OF PURE SCIENCE 241 



other; alternate, when some of the hybrids are like one parent and 

 some like the other; and the so-called unisexual inheritance, when all 

 the hybrids tend to resemble one particular parent. Entirely new and 

 unexpected fields of experimentation have been brought out by Mendel's 

 study of alternate, and De Vries's examination of unisexual inherit- 

 ance. This theoretical work also teaches that in practise attention 

 should be given not so much to the whole individual as to the particular 

 quality desired. The remarkable work of De Vries, the most impor- 

 tant in evolution since the time of Darwin, would tend to show that 

 though new forms may be produced by crossing, such crosses are usually 

 not permanent, but tend to revert. De Vries's particular contention is 

 that stable new forms, those that breed true, are not produced gradually 

 by selection or otherwise, but arise suddenly and only in particular muta- 

 tion periods. This introduces an entirely new attitude in the matters 

 of selection and cross-breeding, and there can be no doubt that tbe 

 scientific decision of these great problems will come to exert a great 

 influence upon the progress of agriculture. It is the work of theorists 

 that is here directing, stimulating and explaining, and it is changing 

 the present haphazard experimentation, with its great loss of time and 

 money, into accurate control. 



If farmers would only do a little experimenting on their own 

 account, each laying aside a small piece of ground for making tests, 

 they would learn more of practical advantage than by following, year 

 in and year out, the methods handed down by their forefathers. They 

 would be doing a little scientific explanation, and though this might 

 not immediately give them an additional bale of cotton, in time it 

 would give them much more than that and would fill them with greater 

 interest for their daily labors. The farmers are the backbone of the 

 nation, and that spine must not get the rheumatism. A man must 

 look before he leap, and science does the looking. As Franklin put 

 it : " The eye of a master will do more work than both his hands." 

 Indeed, the farmer comes into close touch with biological problems 

 because his business is directly with plants and animals, and though 

 he does not know it he is really a biologist in the rough. When the 

 competition for market becomes keener, and it continues to do so as 

 men become more trained, only he will be able to succeed who is armed 

 with a working theory and by means of it aims at better results. In 

 farming it is not the land so much as the man. To get at a new plan 

 so as to use his time and brawn to the best advantage, the farmer must 

 begin to explain and must use the explanations of science. A hen 

 can not grow into a rooster, but it can be made to lay two eggs a day. 

 The question of the qualities and possibilities of living beings is the 

 subject-matter of biology, and the more we understand them the more 

 we can use them. But we must remember that we can apply only when 



VOL. LXXIII. — 16. 



