Note 13 — APPENDIX II
George Kamensky translation
In this sense, oxalic acid, (COOH)2, also corresponds to carbonic acid, OH(COOH), in the same way that dithionic acid corresponds to sulphuric acid, and subphosphoric acid to phosphoric; hence, if a peroxide corresponding to carbonic acid be obtained, it will have the structure of (HCO3)2, or H2C2O6 = H2O + C2O5. So also lead must have a real peroxide, Pb2O5.