MEMOIll OF CAMPER. 
21 
Medicine, on which occasion he published two dis- 
sertations, the one On Vision, and the other On 
Certain Parts of the Pye, botli of which have been 
preserved by Haller. In the former, he illustrates 
and defends Smith’s theory of vision, and in the lat- 
ter he describes and gives plates of the canal of Pe- 
tit, in the eyes of several of the lower animals. 
The acquaintance which Camper had formed with 
several foreigners of merit, had long inspired him 
with the desire of travelling, and gratifying his thirst 
lor knowledge, by visiting dilferent countries, and 
conversing with men distinguished for their acquire- 
ments in the several branches of science. But the 
'iedining health of his parents, who were now ad- 
vancing in years, and required the continual presence 
and kindest attentions of their son, long prevented 
him from accomplishing his wishes. Their death, 
however, wdiich happened in 1748, released him 
fi'om duties which he had the consolation of reflect- 
ing had been assiduously discharged ; atid he soon 
after, at the age of twenty-six, embarked for Eng- 
land. 
Furnished with the best letters of introduction, he 
aoon made the acquaintance of many of the most emi- 
nent scientific men in London, and assiduously attend- 
ed the courses of instruction which were then deliver- 
ed. Of the individuals who thus became his masters 
and future friends, we may mention, among medical 
men. Dr Mead and the Hunters, Smellie, Pringle, and 
Pitcairn ; whilst by his intercourse with such men 
