262 T. S. Hunt on the Theory of Types in Chemistry. 
ygen in reacting upon the hydrogen of the water type, and the 
acids may be accordingly represented as found by the substitu- 
tion of the residue PO, —O, for H, ete. 
this manner of representing the generation of polybasic 
acids we object that it encumbers the science with numerous hypo- 
thetical radicals,* and moreover fails to show the actual succes- 
phoric anhydrid P,O,,=(PO,),0, is placed in contact with 
water it combines with one equivalent, H,O,. The union is 
followed by homogeneous differentiation, and two equivalents of 
metaphosphorie acid result; (PO,),0,+H,O, =2(PO,H)0,. 
Two equivalents of this acid in contact with one of water at 
common temperatures are slowly transformed into two of pyro- 
phosphoric acid, by a reaction~ precisely similar to the last; 
2(PHO,)=(PHO,),0,+H,O, =2(PHO,.H)O,; and two equiv- 
alents of pyrophosphoric acid when heated with a third equivalent 
of water yield in like manner two of tribasic phosphoric acid; 
2(PH,O,)=(PH,O,),0,+H,0,=2(PH,0,.H)O,=2PH,9,- 
was on aving for four years opposed them to 
Gerhardt, that this chemist in J ie 1809, renounced his former 
views, and without any acknowledgment, adopted my own (An”- 
- - Al my 
‘veloped the ideas relative to the water type to which Wartz 
h editor of Gmelins 
Those who are familiar with chemical literature will remember an 2 
jeu Mesprit of the lamented Laurent in which ia invited the attention of the adyo- 
cates of the radical theory to a new electro-negative radical which he Euthi- 
zene, (Comptes Rendus des Travauz de Chemie, 1850, pp. 251 and 376). It was pot 
without a smile that we observed a late writer in The Chemical News, vol. i, 326, 
proposing as a newly invented radical under the name of hydrine, the peroxyd 
hydrogen HOs, the eurhizene of Laurent! ee 
amusing — 
