526 
MESSRS. T. E. THORPE AND J. W. RODGER OX THE RELATIONS 
As the boiling-point of the ortho-xylene employed (144°'07) is nearly 2° higher 
than that usually assigned to this hydrocarbon, Dr. Moody was good enough to 
prepare a second sample from the sulpho-chloride. This was reconverted into the 
acid by boiling with alcohol, and the acid was afterwards hydrolised. The hydro¬ 
carbon was dried over sodium wire and distilled. It boiled between 143°'75 and 
144°‘02. Bar. 7 57'6 millims. Corrected and reduced b.p, = 144°‘01. 
It will be observed that the boiling-point of the second sample is almost identical 
with that of the first. 
An observation of its vapour density gave :— 
Found, 52’88. Calculated, 53*00. 
Observations on the viscosity of the second sample were made with the following 
results :— 
Left limb. 
Right limb. 
Temp. 
Press. 
Corr. 
Temp. 
Press. 
Corr. 
'/• 
O 
035 
103-41 
-000024 
■010969 
O 
0.35 
103-84 
■000024. 
•010978 
13-04 
103-47 
-000029 
■008936 
12-97 
103-37 
■000029 
•008950 
26-97 
103-54 
-000035 
■007337 
26-80 
103-44 
■000035 
-007358 
38-73 
103-57 
-000040 
■006313 
38-73 
103-49 
■000040 
•006323 
51-18 
103-40 
-000045 
■005483 
51-13 
103-35 
■000045 
•005488 
65-95 
103-22 
-000052 
■004695 
65-89 
103-16 
■000052 
•004703 
77-46 
103-13 
■000057 
■004203 
77-50 
103-07 
•000057 
•004205 
90-32 
103-02 
■000063 
■003741 
90-42 
102-96 
•000063 
•003740 
100-68 
102-73 
■000067 
■003430 
100-75 
102-65 
•000068 
•003428 
115-67 
102-54 
■000075 
■003032 
115-64 
102-47 
•000075 
•003036 
128-75 
102-37 
■000081 
■002748 
128-63 
102-31 
•000080 
•002749 
1.39-89 
102-23 
•000086 
■002533 
139-90 
102-17 
•000086 
•002536 
In reducing the observations the same values for the relative density and thei’mal 
expansion were used as in the first series. 
On plotting the results, the observations on the second sample are seen to be 
practically identical with those of the first. For temperatures up to 20° those of the 
second ai'e about 0*1 per cent, greater than those of the first ; from this point up to 
about 100° the curves are absolutely coincident; from 100° up to the boiling-point the 
observations of the second series are about 0'3 per cent, less than those of the first. 
The case is interesting as showing the practical identity of the two samples, and as 
proving that a substance prepared in totally different ways may be obtained in a 
condition so closely approximating to absolute purity that the degree to which it 
may fall short of this ideal state is without appreciable eftect on the property we are 
measuring. 
