274 Dr. Schunck on Rubian and its Products of Decomposition. 



iron does not dissolve chlororubiadine, nor does the colour of 

 the solution change during boiling. The alcoholic solution of 

 chlororubiadine reddens litmus paper. The solution gives no 

 precipitate with acetate of lead, not even on the addition of 

 ammonia, but with acetate of copper it gives after some time a 

 copious light brown precipitate. Acetate of alumina and per- 

 acetate of iron produce no change in the alcoholic solution. An 

 alkaline solution of chlororubiadine reduces chloride of gold to 

 the metallic state. 



The composition of chlororubiadine was determined by the 

 following analyses : — 



I. 0*5650 grm., dried at 100° C. and burnt with chromate of 

 lead, gave 1*2630 carbonic acid and 0*2130 water. 



0*4850 grm., burnt with lime, gave 0*2200 chloride of silver. 



II. 0*4620 grm. of a second preparation gave 1*0260 carbo- 

 nic acid and 0*1760 water. tG-j!. j itirw i- )MJJ^;L• 

 III. 0*5475 grm., made from the last by dissolving it in 



ammonia, adding chloride of barium, filtering the liquid from 

 the dark flocks which were precipitated, allowing the baryta 

 compound to crystallize, decomposing it with muriatic acid, 

 and crystallizing what was left by the acid from boiling alcohol^ 

 gave 1*2280 carbonic acid and 0*2100 water. -^ 



0*6260 grm. gave 0*2775 chloride of silver. 



IV. 0*4980 grm. of another preparation, obtained like the 

 last from the bai*yta compound, gave 1*1130 carbonic acid and 

 0*1905 water. 



0*7680 grm. gave 0*3455 chloride of silver. 



Hence the following composition may be deduced : — 



Eqs. Calculated. I. II. III. IV. ^ 



Carbon . 32 192 61-65 6096 60-66 61-17 60*95 

 Hydrogen. 12 12 385 418 4-23 426 4-25 



Chlorine. 1 35-4 1136 1121 ,1^{^^M^'^. H'lO 



Oxygen . 9 _72_ 23-14 23-65 ^r ^ ^^23*^ ' 23-70 

 311*4 10000 10000 10000 100-00 



The baryta compound I found to have no very simple compo- 

 sition. It was prepared, as above described, by dissolving cry- 

 stallized chlororubiadine in ammonia, adding chloride of barium, 

 filtering from a few flocks that were precipitated, and allowing 

 to crystallize in an air-tight flask, filtering, washing with water, 

 and drying in vacuo, 



0*8370 grm. of the crystals lost, on being heated for some 

 hours in the water-bath, 0*0690 water =8*24 per cent. 



0*5770 grm. of the substance thus dried gave, when burnt 

 with chromate of lead, 1*0965 carbonic acid and 0*1790 water. 



0*5660 grm. gave 0*1350 sulphate of baryta. 



These numbers lead to the formula 4C^^ W^ ClO^-f-SBaO, as 



