274 PROCEEDINGS OF THE AMERICAN ACADEMY 



linking terms, and again of others in which, besides the replacement 

 of hydrogen, phosphorus may be replaced by arsenic, and possibly 

 b}^ antimony and other elements. 



2. Vanadium may replace phosphorus and arsenic so as to form 

 well-defined series of vanadio-molybdates and vanadio-tungstates em- 

 braced under the general formula 



m 



RO3 . n V2O5 . p RI2O. 



3. Vanadic and phosphoric pentoxides may enter simultaneously 

 into combination with tungstic or molybdic oxide, so as to form classes 

 of triple acids embraced under the general formula 



m RO3 . n P.O. . p V2O5 . V II2O. 



4. A class of quadruple acids exists into which, in addition to phos- 

 phoric and vanadic pentoxides, vanadic dioxide may enter, the general 

 formula being 



m RO3 . n P2O5 . p V2O5 . r VO2 . v ll.Jd. 



5. In another class of ternary or triple acids molybdic or tungstic 

 oxide may be combined with both vanadic pentoxide and vanadic 

 dioxide, the general formula being 



m RO3 . n V2O5 . p VO2 . V H2O. 



I shall show hereafter that all of these results are capable of further 

 generalization ; that, for example, other oxides of the types RO2 cor- 

 responding to hydrates of the form R(OH)^ may replace VO2 or 

 V(OH)^; that other pentoxides may replace F.20^, AS2O5, and V2O5, 

 either in the presence or in the absence of oxides of the type RO2 ; in 

 short, that the complex inorganic acids form a new department of inor- 

 ganic chemistry, and not a series of isolated compounds. 



(2b be co7itinued.) 



