MR. SCHUNCK ON RUBIAN AND ITS PRODUCTS OF DECOMPOSITION. 409 
VI. 0‘5320gTm. gave I'OOOO carbonic acid and 0‘2380 water. 
0'9370 grin., burnt with lime, gave 0'2450 chloride of silver. 
These numbers correspond in 100 parts to — 
I. 
II. 
III. IV. 
V. 
VI. 
Carbon . 
. . 51T5 
51-06 
51-20 51-27 
51-14 
51-26 
Hydrogen 
. . 5-04 
4-88 
4-87 4-92 
5-00 
4-97 
Chlorine 
. . 6-54 
?? 
6-45 6-26 
6-28 
6-46 
Oxygen . 
. . 37-27 
35 
37-48 37-55 
37-58 
37-31 
There are several formulee which give 
a composition in 
100 parts agreeing tole- 
rably well with 
these numbers. 
but only 
one which at the 
same time 
explains the 
manner in which chlororubian is 
1 formed. 
This formula is C 44 H 27 CIO 24 , 
which gives 
the following composition : — 
Eqs. 
Carbon 
. . 44 
264 
50-92 
Hydrogen 
. . 27 
27 
5-20 
Chlorine . 
. . 1 
35-4 
6-82 
Oxygen 
. . 24 
192 
37 -O 6 
518-4 
100 00 
Assuming this formula to be correct, then rubian, when acted on by chlorine, loses 
1 equivalent of hydrogen, which is replaced by chlorine, at the same time taking up 
6 equivalents of water and splitting up into chlororubian and sugar, as will be seen 
from the following equation ; — 
C,6H3,03o+6HO+2C1=C,,H,7C10,,+C>,H.,0„+C1H. 
Action of Acids on Chlororubian . — If chlororubian be treated with boiling dilute 
sulphuric or muriatic acid, it first dissolves to a yellow liquid, but on continuing to 
boil, the solution suddenly becomes milky and deposits a large quantity of yellow 
crystalline flocks. The filtered liquid is almost colourless, and contains sugar. The 
flocks consist entirely of a body, to which, as it has the composition of rubiadine in 
which 1 equivalent of hydrogen is substituted by chlorine, I shall give the name of 
Chlororuhiadine. It is purified by collecting the flocks on a filter, washing them 
with water, and dissolving them in boiling alcohol, which on cooling and standing, 
deposits yellow shining crystals, which are larger than those of chlororubian. 
Chlororuhiadine has the following properties. When crystallized from alcohol and 
dried, it has the appearance of a yellow mass, consisting of small shining crystalline 
needles and scales. When heated on platinum it melts to a brown liquid, and then 
burns with a yellow flame bordered with green, leaving much carbonaceous residue. 
When heated in a tube it melts and gives penetrating fumes, smelling of muriatic 
acid, and forming on the colder parts of the tube a sublimate which is at first oily but 
soon becomes crystalline. It is insoluble in boiling water. Dilute nitric acid does 
not affect it, even on boiling. Nitric acid of sp. gr. T52, however, dissolves it, even 
3 I 2 
