597 
toluene contains: 
Isomer | 
P29 | 1,2,4 | 1,2,6 | 2,3 | 
De | 43.3 | 17.0 | 20.5 } 19,2 | 
in which the figure for 1, 2,3 is obtained by subtraction. It may be 
observed, that this method of analysis was first tried with good 
result on artificial mixtures of the four nitro-o-toluenes. 
For the application of this method of quantitative analysis, it is 
necessary to possess the isomers present in the nitration product in 
a perfectly pure state. This presented some difficulty with the nitration 
product of m-chlorotoluene, the nitro-m-chlorotoluenes being hardly 
known and surely not obtained chemically pure until now. I shall not 
give a description of their preparation and purification here, but 
only mention that the isomer 1, 3, 6 (CH, = 1, Cl = 8) solidifies 
at 24°.9, the ‘isomer 1,3,4 at 24°.2, the isomer 1,3, 2 at 23°.4, 
and the isomer 1, 3,5 at 58°.4. 
The quantitative nitration of m-chlorotoluene was executed in the 
same way as is described for o-chlorotoluene. By applying the 
method VarreroN on the nitration product, we found for its composi- 
tion the following figures: 
Isomers | 456 | RG | heo 
Percentage | 58.9 | 32.2 | 88 
The figure for the isomer 1, 3,2 is the difference of the sum of the 
two isomers from 100, the method Vaturon giving only more exact 
results as the quantities to be determined are larger. On the other 
hand however, we found by direct determination an amount of 
8.3 °/,. We believe it therefore proved with certainty that this isomer 
is present in the nitration product, and that the isomer 1, 3,5 is 
not present in it in an appreciable quantity. The presence of the two 
other isomers was already known by an investigation of RrVERDIN. 
From the figures obtained in analyzing the nitration products of o-, 
m-, and p-chlorotoluene we may now draw the following conclusions. 
In o-chlorotoluene, methyl- directs the entering substituent to the 
CHs places 4 and 6, chlorine to the places 3 and 5. They act 
("3 therefore independently of one another, the little quantity 
See of m-compound that is formed in the nitration of toluene 
beingt left out of consideration. 
When the velocity of substitution, caused by methyl and chlorine 
were the same, the isomer nitro-o-chlorotoluenes would be formed 
in the same proportion as in the nitration of chlorobenzene on one 
