Colour a7id Chemical Constitution. 
133 
efhi and efhj ; efi combined with j, k and I ; egi with Jc and I and ehil ; and 
filially fgij,fgik,fgil Siiid fgjk. Of this multitude of isomers only two could 
be prepared, viz. : 
Tetrahromophe7iolplit}ialei7i8. 
Position of bromine 
atoms. 
Method of formation. 
Observed band- 
centre. 
Calculated from 
position-law. 
a-b-c-d 
Tetrabromplithalic acid and phenol 
X 583* 
X 583 
Dibi'omo-OBBA and 2-6-dibrom- 
X 584 
X 584 
phenol, also by bromination of 
phenolphth alein 
* The figures given in Part 1, 1917, of this work for this substance and the thymol 
derivative are erroneous. 
Taking account of the foregoing convention about the (^-position, I find 
that the number of possible pentabromophenolphthaleins is 118. I have 
made and observed only those which are derived from the mono-derivatives 
by perbromination. 
Pe7itahro7no])he7iol2)Mhaleins. 
Position of bromine 
atoms. 
Source. 
Observed band- 
centre. 
Calculated from 
position-law. 
O'-f-g-h^ 
h (or c)-f-g- 
e-f-g-j-Tc 
a-monobromophenolphthalein 
4-bromophthalic acid -f phenol -f 
bromine 
e-monobromophenolphthalein 
X597 
|X592 
X 602 
X594 
. . J 585 h 
1 592 c 
X 599 
As regards the hexabromophenolphthaleins, the possible number is 134, 
taking account of the convention. Again I have only observed those 
obtainable by perbromination of lower brominated substances. 
Ilexahro7no]_)lie7iolpht]ialeins. 
Position of bromine 
atoms. 
Source. 
Observed band- 
centre. 
Calculated from 
position-law. 
a-d-f-g-j-Tc 
(i-c-f-g-J-^ 
h-c {?)-f-g-j-k 
c (?)-e {?)-f-g- 
a-(J-dibromphenolphthalein 
a-o-dibroniphenolphthalein 
3rd dibromo-compound 
Bromine on ordinary tetrabromo- 
compound* 
X 606 
X 602 
X 592 
X 605 
X 604 
X 602 
X 593 
X 607 
* Only a trace obtained. 
