On Dr. Mitchill's Theory, ^c. ^5 



ji)tari of a new telegraph, and a telegraphic language, accom- 

 panied with a dictionary of 13,000 French words adapted 

 to it by a combination worthy of fo able a mathematician. 



Thefe labours had injured his health; he had been a long 

 time althmatic, and notwithflanding his condition he pab- 

 liflied, that year, an excellent memoir on finding the longi- 

 tude at fea, under the modeft title of A Suppiancnt to the 

 Trlgononiiitry and ]\a-jlgation of Bezout. He died on the 

 14th of Nmeniber 1798, leaving behmd him a daughter, 

 born at Vannes in 1793. According to a tradition in the 

 Familv, he was defcended from Defcartes. I have not been 

 able to obtain the genealogy of his faimily; but it is lufficient 

 for the glorv of Callo, that he has done honour to a name 

 fo celebrated. 



Vr. Progre/} of Dr. Mitchill'j Mind in invrfttgating the 

 Caufc of the Pcjlilsntial Di/letnpers luhich "Sijit the Cities of 

 Avierica in Sum7ncr and Aiitum?i. Being a Developement 

 of his Theory of PeflHential Fluids, as fubli/hed to th& 

 World ill 17955 and the fuccceding Years^. 



iThad a long time appeared to him, that what ha;d becri 

 mentioned by medical writers and lecturers under the names 

 6f viiujma and coniiigion, was not treated of with the pre- 

 cifion and certainty of knowledge, but difcufled with all the 

 indiftinftnefs and conjefture of fomething only guefled at. 

 And, while a ftudent at Edinburgh, he fuppofe'd the doftrine 

 taught in the univcrfity of the fedative operation of thefe 

 poifons was true, until he heard from Dr. Brown, while at- 

 tending his leftures, a contrary opinion- 

 Delivering his fentiments on jihnulants, Brown had faid, 

 *' Vencna ct contagiones incertitis eodcm fpeftant." (Ele- 

 menta Medicince, cap. 2. § xl.) This implied a doubt in 

 Brown's mind, whether thefe clafles of objecls were flimu- 



• From an Ait erican Corrcfpoadcnt. 



D % Jant? 



