318 MESSRS. E. FEANKLAND AND B. F. DUPPA'S 



Diethoxalic acid is very soluble in alcohol or ether, and somewhat less so in water. 

 By the spontaneous evaporation of its aqueous solution, it crystallizes in minute prismatic 

 needles ; but if a small quantity of dilute sulphuric acid be added to the solution, the 

 crystals are deposited in magnificent anorthic prisms, which frequently attain a length of 

 1 inch and a thickness of ^ inch. 



Diethoxalic acid is greasy to the touch, like stearic acid ; it fuses at 7 4°' 5 C, and slowly 

 sublimes at the same temperature, but is decomposed before reaching its boiling-point. 

 It has a sour taste, reddens litmus strongly, and expels carbonic acid from bases. It 

 forms an extensive series of salts, which are all soluble in water. In addition to the 

 barium-salt described above, we have examined the silver, copper, and zinc salts. 



Argentic dietJioxalate is readily prepared by boiling an aqueous solution of the acid 

 vnth excess of argentic carbonate. On filtration and evaporation in vacuo, the salt cry- 

 stallizes in brilliant needles, radiating from centres standing up freely firom the capsule, 

 and containing half a molecule of water, which is not expelled at 100° C. 



Submitted to analysis this salt gave the following numbers, indicating the formula 



Cg Hn O, 



..^0.(H,0),or{CEt^Ho^(H,0).. 



Ag ^ ' '^ iCOAg 



•5035 grm. gave -5283 grm. carbonic anhydride, -2248 grm. water, and -2158 grm. 

 silver. 



Calculated. Found. 



Cg .... 72 29-03 28-62 

 Hi2 . . . . 12 4-84 4-96 

 O,. .... 56 22-58 



'Si 



Ag .... 108 43-55 42-86 



248 100-00 



Cupric dietJioxalate is obtained by mixing atomic proportions of baric diethoxalate 

 with cupric sulphate, filtering, and evaporating to dryness. The salt does not crystallize, 

 but dries down to a green gum-like mass, which becomes nearly white on being reduced 

 to powder. Submitted to analysis, it yielded the following results : — 



I. -3380 grm., burnt with cupric oxide, gave -5460 grm. carbonic anhydride and -2120 

 grm. water. 



II. -2090 grm. gave -0505 grm. cupric oxide. 



These numbers agree with the formula 



fCEtgHo 



lcoo|c^„ 



fCOOi 



ICEtgHo ■ • 



