BETWEEN THE VISCOSITY OF LIQUIDS AND THEIR CHEMICAL NATURE. 525 
Ortho-xylene (Ortho-dimethyl benzenej. 0 ( 5114 ( 0113 ) 3 ( 1 : 2 ). 
Two specimens of this hydrocarbon were employed in the determination of its 
viscosity. The first was prepared for us by Dr. G. T. Moody from Witte’s “ pure” 
ortho-xylene. The hydrocarbon was sulphonated with ordinary sulphuric acid, and 
the product converted into the barium salt, and ultimately into the sodium salt, 
which was then repeatedly crystallised from water. The pure sodium salt, which 
forms large, characteristic plates, was hydrolysed by mixing it with sulphuric acid 
and injecting steam into the solution. The hydrocarbon thus obtained was dried 
over sodium and distilled, the first and last portions of the distillate being collected 
apart. 
The middle fraction was placed over sodium wire for about a fortnight and again 
distilled. It boiled between 144°'00 and 144°'08. Bar. 759T millims. Corrected 
and reduced b.p. = 144°'09. 
The determination of the boiling-point was subsequently repeated. The hydro¬ 
carbon was found to boil at 144°‘35 under a barometric pressure of 766’2 millims. 
Corrected and reduced b.p. = 144‘^'05. 
Observation of vapour density :— 
Found, 52’59. Calculated. 53’00. 
The observations for viscosity gave the following results :— 
Left limb. 
Right limb. 
Temp. 
Press. 
Con’. 
Temp. 
Press. 
Corr. 
'/• 
0 
0-45 
102-78 
-000024 
-010927 
0 
0-54 
102-65 
-000024 
-010928 
13-87 
102-70 
-000029 
-008805 
13-89 
102-62 
-000029 
-008814 
26-53 
102-96 
-000034 
-007379 
26-55 
105-25 
-000035 
-007386 
39-35 
102-95 
-000040 
-006279 
39-;32 
102-85 
-000040 
-006284 
51-92 
103-00 
-000046 
-005437 
51-97 
102-89 
■000045 
-005441 
65-40 
103-02 
-000051 
-004728 I 
65-42 
102-94 
-000052 
-004735 
78-78 
103-14 
-000058 
-004156 1 
78 79 
103-03 
-000058 
-004159 
90-82 
103-22 
-000063 
-003726 1 
90-82 
103-13 
-000063 
-003733 
101-80 
103-38 
•000068 
-003403 1 
101 76 
103-35 
-000068 
-003403 
116-49 
103-40 
-000076 
-003023 : 
116-74 
103-31 
-000075 
-003015 
128-33 
103-44 
-000081 
-0U2762 ! 
127-98 
103-31 
-000081 
■002769 
140-99 
103-44 
-000087 
-002519 ! 
1 
141-29 
103-35 
-000087 
-002515 
In reducing the observations, Pinette’s expression for the thermal expansion, 
V = 1 -h -0391734^ + -0513245^2 + - 0819586 ^ 3 , 
and his value for the relative density, d (0°/0°) = 0‘8932, have been employed 
(‘Annalen,’ 243, 50, 1884). 
