346 NATURAL SCIENCE [November 



I may mention in this case a rather instructive lesson learnt from 

 the growing of crops of Datura tatula for medicinal purposes. 

 Among the plants there are two marked varieties — (1) The respect- 

 able class who most fulfil the purpose for which they are grown, by 

 producing most leaf and stalk per acre ; (2) The waster class, whose 

 sole object in life seems to be to produce seed. Now if the indi- 

 viduals of the two classes were numerically equal in one generation, 

 and seed were saved equally from the whole, class 2 would far out- 

 number class 1 in the subsequent generation because of its greater 

 fecundity. But class 2 has a worse character than this — it not only 

 produces more seed but it makes sure to ripen that seed the earlier, 

 so that when the crop is cut there is far more ripe seed of class 2 

 than there is of class 1. Wherefore class 1 should in a few years have 

 almost disappeared to vanishing point. 



But artificial selection is far more ruthless than any form of 

 natural selection, so called. We go through the crop with thorough- 

 ness to destroy the plants of class 2, so that there may be no seed 

 from them for the next generation. And yet partly perhaps owing 

 to the immensely greater fecundity of the wasters, partly perhaps 

 to an innate tendency of the respectable class to become wasters, in 

 spite of several years' ruthless efforts at extermination, the individuals 

 of the waster class are as numerous as ever. No alcoholic selection 

 would be as vigorous as that. A fortiori it would fail even more 

 lamentably. 



If Mr Reid could free himself from the fetish of natural selection, 

 and could bring himself to think that acquired characters are in- 

 herited, though he may not know how, then he would find himself 

 aide to account for the increased sobriety of the nations who have 

 longest known alcohol. Such account would take the following 

 form — that familiarity breeds contempt, and that an acquired 

 character of restraint is inherited until it becomes a second habit 

 performed quite unconsciously. 



It is well known that if an individual be introduced to an un- 

 accustomed pleasure he rushes thereat for a while, possibly overdoes 

 it, and then becomes satiated. Instances are all around us. And 

 what is possible for the individual is possible for the race : it may be 

 alcoholically satiated. 



As regards the acquired character of restraint, Mr Eeid doubts its 

 existence. He puts it in the other way, that the craving is less. 

 Here it is said the craving is the same but the power of restraint is 

 greater. The difference is important. If two cycles of equal weight 

 are started at the top of a hill the tendency to run away is equal in 

 both. But if one be fitted with a brake its running away propensities 

 are checked ; not because the craving to run away is less, but because 

 the brake power — the restraint — is greater. And that is the case with 

 man and alcohol. The sober individual and his parents before him 

 have exercised restraint until it has become a second habit — per- 

 formed with as little consciousness as walking. 



And there is a case strictly analogous, in the acquired restraint 

 which man habitually and often unconsciously uses over his bodily 

 functions. In the case of the urinary organs such restraint is the 

 cause of many diseases and frequently of death, wherefore, according to 



