222 PROFESSOR A. CRUM BROWN AND DR JAMES WALKER ON THE 



white or transparent plates. Its melting-point is 123°, and at a higher temperature it is 

 decomposed. 



Analysis — 



•1078 gr. substance gave -2576 gr. C0 2 and -0990 gr. H 2 . 



Found. Calculated for C 14 H 2G 4 . 



C . . . 6517 per cent. 65-12 per cent. 



H . 10-20 „ 1008 



The acid was too sparingly soluble in water to admit of an accurate determination of its 

 dissociation constant. 



The alkaline salts dissolve in water, forming soapy solutions. They are also slightly 

 soluble in alcohol. Salts of the other metals may be obtained from an aqueous solution 

 of the neutral potassium salt by precipitation. From dilute solutions the lithium and 

 magnesium salts are not at once precipitated, but after a time they appear in the micro- 

 crystalline form. This of course is owing to their slight solubility in water. The 

 remaining salts fall out as voluminous precipitates insoluble in water. 



The quantity of metal present was estimated in the following salts : — 



Potassium salt. — "3304 gr. gave '1685 gr. K 2 S0 4 . K found, 23*40 per cent. ; cal- 

 culated for K 2 Ci 4 H 24 4> 23*35 per cent. 



Magnesium salt. — "4856 gr. gave "0690 gr. MgO. Mg found, 8*58 per cent. ; cal- 

 culated for MgC 14 H 24 4 , 870 per cent. 



Barium salt. — '4261 gr. gave "2531 gr. BaS0 4 . Ba found, 34*92 per cent.; cal- 

 culated for BaCi 4 H 24 4 , 34*86 per cent. 



Copper salt. — *3272 gr. gave "0817 gr. CuO. Cu found. 19*92 per cent.; cal- 

 culated for CuC 14 H 24 4 , 19*74 per cent. Blue-green precipitate. 



Silver salt. — "3715 gr. gave *1094 gr. Ag. Ag found, 29*5 per cent.; calculated 

 for Ag 2 Ci 4 H 24 4 , 29*7 per cent. The silver salt is very soluble in ammonia solution. 



The chromium and nickel salts are light green ; the cobalt salt is reddish ; the ferric 

 salt yellow ; and the ferrous salt brown. 



As suberic acid possesses the normal structure, this new acid, from its mode of forma- 

 tion, must also be normal, and correspond to the formula COOH*(CH 2 ) 12 *COOH. With 

 regard to the nomenclature of these acids, we propose to name them as dicarboxyl 

 derivatives of the saturated hydrocarbons. The parent substance of the above acid is 

 thus dodecan, C 12 H 2G , and the acid itself w-dicarbododecanic acid, C 12 H 24 (COOH) 2 . 



The yield is 25 per cent, of the calculated quantity. 



Synthesis of n-Dicarbodecahexanic Acid, COOH*(CH 2 ) 16 *COOH. 



Sebacic acid from castor-oil was converted into the diethyl ether, which was then 

 further transformed into the electrolytic solution of the ethyl-potassium salt in the 

 manner described on p. 217. 



