PROCEEmNGS OF THE POLYTECHNIC ASSOCIATION. 



AN ORGANIZATION UNDER THE CONTROL OF THE 

 AMERICAN INSTITUTE. 



AsiEEicAN Institute Polytechnic Association, ) 



2Iay 10, 1866. \ 



Professor S. D. Tillman in the chair ; T. D. Stetson, Secretary. 



New Chemical Syimbols. 



The chairman opened the meeting by saying, I noAv present in 

 connection with my new chemical nomenclature submitted at the 

 last meeting, a new series of symbols intended to facilitate the 

 acquisition of chemical knowledge. 



The subject is too vast and complex to be embraced in a single 

 lecture. I shall, therefore, only aim to indicate the leading fea- 

 tures of the plan, and to present such rudiments of chemistry as 

 relate more particularly to those elementary substances which are 

 not regarded as metals. 



All matter may be first classed as ponderable and imponderable. 

 The latter I have discussed very fully before the Polytechnic 

 Association at previous meetings. 



Chemists now recognize at least 64 diiferent kinds of ponderable 

 matter which have not thus far been decomposed, and are, there- 

 fore, regarded as simple bodies. Fifty-one of these are called 

 metals and 13 non-metallic elements. French chemists do not 

 draw the line of distinction so broadly, since several of the non- 

 metallics possess nearly all the characteristics of the metals. They 

 recognize 49 of the elements as metals and designate the remain- 

 ing 15 as metalloids. The objection to this classification is, it 

 assumes that all elements which are not metals are like metals. 

 Seven of these metalloids are strongly electro-negative, and in 

 their general behavior bear no resemblance to metals. On examin- 

 ing the non-metallic elements it will be found most convenient to 

 classify them according to the state or condition "vvhich they as- 

 sume when isolated. Three elements are remarkable for their 

 hardness or impenetrability, namely: 



