16 
Bulletm of Natural History Society. 
Prof. Hartt’s scientific career may be said to have cover- 
ed a decade and a half, and one can only wonder at the mar- 
vellous industry which crowded what might well be con- 
sidered the work of an ordinary life-time into this short 
period. Only those engaged in his enterprises knew the 
variety and excellence of his scientific work, or could appre- 
ciate the skill with which he directed the operations first 
of his exploring parties in Brazil, and then of the Geological 
Survey of that vast region. Judging from his brilliant be- 
ginning, we may confidently assert that, had he not been 
cut off in his prime, he would have accomplished a work 
that would have placed him beside the greatest of the geo- 
logical investigators of the ])resent century. 
Kone but the hardiest constitution could stand the great 
strain which Hartt laid on his physical powers, and under 
the exhausting heat of a tropical climate he finally suc- 
cumbed. Having been on an exploring expedition inland, 
he came out upon the coast at Eio de Janeiro tired and 
worn out by physical toil and mental anxiety ; the latter 
due to the difficulties in which the Survey had been placed 
by changes in the administration of the country. Here he 
was attacked by that formidable scourge of the lowlands of 
tropical America — yellow fever. His exhausted system 
could not withstand the disease. His illness was of scarcely 
more than two days duration, and he suddenly (and unex- 
pectedly to those who were watching him) passed away in 
the early morning of Monday 18 th of March 1878 . 
Prof. Hartt was a man of winning manners, affectionate 
disposition and generous nature, and was greatly esteemed 
by his scientific associates. He was gifted with an original 
and inventive mind, and indefatigable industry. The Christ- 
tian training of his early home, and the stimulating influen- 
ces of the educational institutions where he spent the first 
yeai’s of his life, no doubt served largely to form his charac- 
ter. His death terminated the Geological Survey of Brazil, 
as no one was thought worthy of taking the mantle which 
fell from him. His assistants remained to- work up the 
material which he had gathered; but the leading mind 
