DISEASES. 117 



mixed blood it is otherwise ; and the virulence of the 

 secondary symptoms seemed to be, in all the cases that 

 came under my care, in exact proportion to the greater 

 or less amount of European blood in the patient. Among 

 the Corannas and Griquas of mixed breed it produces 

 the same ravages as in Europe ; among half-blood Portu- 

 guese it is equally frightful in its inroads on the system ; 

 but in the pure Negro of the central parts it is quite in- 

 capable of permanence. Among the Barotse I found a 

 disease called manassah, which closely resembles that of 

 the foeda mulier of history. 



Equally unknown is stone in the bladder and gravel. 

 I never met with a case, though the waters are often so 

 strongly impregnated with sulphate of lime, that kettles 

 quickly become incrusted internally with the salt ; and 

 some of my patients, who were troubled with indigestion, 

 believed that their stomachs had got into the same con- 

 dition. This freedom from calculi would appear to be 

 remarkable in the Negro race, even in the United States ; 

 for seldom indeed have the most famed lithotomists there 

 ever operated on a Negro. 



The diseases most prevalent are the following : pneu- 

 monia, produced by sudden changes of temperature, and 

 other inflammations, as of the bowels, stomach, and 

 pleura ; rheumatism ; disease of the heart ; but these 

 become rare as the people adopt the European dress ; 

 various forms of indigestion and ophthalmia ; hooping 

 cough comes frequently ; and every year the period 

 preceding the rains is marked by some sort of epidemic. 

 Sometimes it is general ophthalmia, resembling closely 

 the Egyptian. In another year it is a kind of diarrhoea, 

 which nothing will cure until there is a fall of rain, and 

 anything acts as a charm after that. One year the 

 epidemic period was marked by a disease which looked 

 like pneumonia, but had the peculiar symptom strongly 

 developed of great pain in the seventh cervical process. 

 Many persons died of it, after being in a comatose state 

 for many hours or days before their decease. No inspec- 

 tion of the body being ever allowed by these people, and 

 the place of sepulture being carefully concealed, I had to 

 rest satisfied with conjecture. Frequently the Bakwains 

 buried their dead in the huts where they died, for fear 

 lest the witches (Baloi) should disinter their friends, and 

 use some part of the body in their fiendish arts. Scarcely 



