SCIENCE -Supplement. 



FRIDAY, FEBRUARY 19, 1886. 



V1RCH0W ON ACCLIMATIZATION. 



At the congress of German naturalists and 

 physicians held at Strasburg, Professor Virchow, 

 the eminent pathologist, delivered an address on 

 'Acclimatization and the Europeans in the col- 

 onies,' of which the following is an abstract. 



In these days of colonization, in which large 

 numbers of human beings leave their homes and 

 settle in foreign lands, under strange and un- 

 accustomed conditions, the subject of the probable 

 influence of such change upon themselves and 

 their descendants becomes highly important from 

 a practical point of view. The key to this problem 

 is in the hands of physicians. With one or two 

 notable exceptions, the subject has been neglected 

 by scientific men. An opinion is current, and is 

 often believed by those who send out colonies, 

 that man is able to adapt himself to living on any 

 part of the earth ; that he is cosmopolitan in the 

 widest sense. This view has allied itself to the 

 monogenetic theory; winch believes in the original 

 common origin of all mankind from one pair, 

 because thus this cosmopolitanism would simply 

 be the return to former conditions. It was the 

 changes from this primitive condition which 

 caused the variations in the races of men. 



Pathology is to be regarded, not simply as the 

 study of the action of accidental causes upon 

 man, which change* his normal condition, but as 

 necessary a science as physiology. Every biologi- 

 cal science, zoology, botany, must have its pathol- 

 ogy. It is a method of research, an experiment 

 in vivisection which nature has made for us with- 

 out shedding a drop of blood. From this point of 

 view, all deviations, at first perhaps accidental, 

 which become fixed by heredity, belong to the 

 field of the pathologist. That such pathological 

 variations are possible, one case is sufficient to 

 show. A woman had a congenital defect of the 

 arm, in which the radius was bent in a peculiar 

 position, and the thumb of each hand was want- 

 ing. This woman's child was affected precisely in 

 the same way, except that on one hand the thumb 

 was in a rudimentary condition. In neither case 

 was there an injury, but the accidental variation 

 was transmitted. The question of the permanent 

 acquisition of these pathological traits is a more 

 difficult one. 



The effects of a new climate upon the emigrant 

 are well known, and are greater as the conditions 

 of his new home differ more radically from those 

 of his mother-country. A sort of new growth 

 must take place, a new adaptation to the environ- 

 ment. A prominent symptom is a feeling of 

 languor, which lasts for days, weeks, or even 

 months. Two kinds of disease are apt to beset the 

 emigrant : the first is the climatic indisposition 

 already mentioned ; the second, the real climatic 

 disease. The life of the individual is then in dan- 

 ger, until the question is decided whether his body 

 has the power of adopting the new conditions or 

 not. It is on this point that clinical observations 

 in different countries are needed. In this organic 

 transformation of the individual the fate of his 

 descendants is involved. It is here that ethnol- 

 ogists become interested to find proofs for their 

 theories that small variations become fixed and 

 lead to racial differences. Experimental evidence 

 on this point is still wanting. 



The question of greatest interest to us is, To 

 what extent has the white race, in its historic 

 evolution, shown the power of adaptation? The 

 white race is not a simple one, and distinctions 

 mnst be made. The Semitic, as opposed to the 

 Aryan branch, has a very great superiority in this 

 respect. Again, the southern nations — Span- 

 iards, Portuguese, Sicilians — have a greater pow- 

 er of adaptation than the northerners. In the 

 colonization of the Antilles, the attempts of the 

 English and French have been more or less disas- 

 trous, while those of the Spaniards have been 

 quite successful. The general proposition, which 

 is only a provisional one, seems to be that a 

 southern people can emigrate to an equatorial 

 region without danger. The readiness with which 

 a population mixes with another is also of impor- 

 tance. The more southern Aryan peoples more 

 easily assimilate with the Semitic element than 

 the northern ones. This Semitic element, which 

 appears early in the Phoenician expeditions to 

 foreign lands, is best suited for founding per- 

 manent colonies. To this day, relics of the settle- 

 ments all along the coast of the Mediterranean, 

 made by Semitic people, can be traced. 



Those white races which cannot become accli- 

 matized without great loss may be called vulner- 

 able, and the regions of the globe which are open 

 to them are very limited. 



North America is one of these favorable regions. 

 The French were able to found a flourishing and 



