PATHOLOGICAL VARIETIES. 59 



Africans are evidently, at least in parts, exempt from these two 

 diseases, which only attack them with a very minor force. It 

 has been said that the question of marsh -poisoning is still ' 

 very doubtful ; it was allowed that the Negroes were less ex- 

 posed to its attacks than other men, but it was desired to 

 enter the question of acclimatisation* into the calculation of 

 facts. All the countries we know that are inhabited by blacks, 

 being nearly all subject to the noxious influence of marshes, it 

 was pretended that even stranger Negroes had acquired from 

 infancy, in their own country, an immunity by which they 

 benefited later in life, and even had the power of handing it 

 down to their descendants, f It is thus that some have ex- 

 plained, for instance, the unhappy results of the English 

 expedition to the Niger in 1841. Out of 145 whites belonging 

 to the crews, the three vessels, after a navigation of about 

 forty -nine days on the river, had lost 40 men (130 were at- 

 tacked). Out of the twenty-five coloured men embarked in 

 England, and who were mostly born in America, eleven were 

 seized with illness, but not one of them died.J This indivi- 

 dual acclimatisation can only be either a fiction, or a proof in 

 support of the ideas which we defend. In the presence of a 

 morbid influence which shows itself and continues, two things 

 alone can happen, either destruction, or permanent (that is 

 to say, specific) modifications of oeconomy, in harmony with the 

 ordinary manner in which this animal population continues to 

 exist. 



* ["The great question of acclimatisation has hitherto been treated 

 lightly enough. ' A firm resolution not to be conquered by a malady/ says 

 Malte-Brun, ' is, in the opinion of most doctors, one of the most efficacious 

 preventives of disease. Our body depends on our intelligence. In every 

 climate the nerves, the muscles, the blood-vessels, in relaxing or in stretch- 

 ing, in dilating or in contracting, soon take the particular state which suits 

 the degree of heat or cold which is borne by the body.' Thus, according to 

 this celebrated geographer, man has only to exercise his will in order to ac- 

 commodate his organism to all the difficulties of a new temperature and a 

 new climate." H. J. C. Beavan, The Acclimatisation of Man (Social Science 

 Review, February 21, 1863.) EDITOR.] 



f Hirsch, Handbuch der Historisch-Geographischen Pathologic, 10. With 

 the author of this immense compilation we refer our readers (with reference 

 to this relative immunity of Negroes from marsh-fever) to the works of Jobin, 

 Tschudi, M'Cabe, Hunter, Arnold, Cameron, Heymann, Epp, Bartlett, Thom- 

 son, Tidyman (Philad. Journ. of Med. Science, vol. iii, No. 6), etc. 



J Epidemiological Society, 3rd June, 1861 ; Medical Times and Gazette, 29th 

 June, 1861, No. 574. 



