434 Scientific Intelligence, 



shores of the Lakes Erie and Michigan, this is a sulphuret of 

 mercury, and yields about sixty per cent. It is so easy to be 

 obtained, and in so convenient a form for distillation, that it 

 must become an important article of commerce." 



The native lead was found on the Anglaize River, at a con- 

 siderable distance from the fort. 



Of this he says, " metallic lead is so interspersed with ga- 

 lena, as to prove incontestably the existence of native lead." 

 Respectfulfy, 



Your obedient Servant, 



J. L. COMSTOCK. 

 Hartford, Conn. Feb. 17, 1819. 

 Benjamin Silliman, M. D., ^c. 



2. Theoretical views of Professor Hare of Philadelphia. 



We are authorized to mention, that Dr. Robert Hare has 

 taught in his lectures during the last eighteen months', that acid 

 properties never appearing in the absence of water, this fluid 

 or its elements are most entitled to be considered as the acidi- 

 fying principle : but that probably it does not exist in acids as 

 water, but is decomposed when added to them, the particles 

 of hydrogen and oxygen by their different polarities taking 

 opposite sides of those composing the base. The extrication 

 of hydrogen by the action of diluted sulphuric acid on iron or 

 - zinc, being the consequence of a previous, not simultaneous 

 decomposition of water. Hence when sulphuric or nitric 

 acids are so concentrated as to char or ignite, they are not 

 acids really. 



3, JVew Work on Chemistry. 



Dr. John Gorham of Boston, Professor of Chemistry in 

 Harvard University, &c. has published the first volume of his 

 Elements of Chemical Science. The work will be comprised 

 in two volumes, and its completion will be anticipated with in- 

 terest by the scientific public. 



