BETWEEiN" THE VISCOSITY OF LIQUIDS AND THEIR CHEMICAL NATURE. 477 
In reducing the observations, the value of 1’249 for the density at 0°, and the 
volumes given by Pierre and Puciiot ('Annales de Chini. et de Phys.’ (4), 22, 314) 
for the thermal expansion, have been made use of. 
Taking 
7)^ = -008196 7/3 = -003229 (calculated) = -005145 
= 0°-34 ^3 = 87°-93 (from curve) = 39°-42, 
we obtain the expression 
_ 472-23 
“ (161-62 + ’ 
which gives the following calculated values :— 
Mean temp. 
V- 
Dilference. 
Observed (mean). 
Calculated. 
O 
0-34 
-00820 
•00820 
•00000 
7-40 
-00745 
•00747 
+ -00002 
16-08 
•00669 
•00671 
+ -00002 
23-71 
■00611 
•00613 
+ -00002 
32-17 
•00556 
•00557 
+ -00001 
40-34 
•00510 
•00509 
- -00001 
48-39 
•00470 
•00468 
- -00002 
56-14 
•00435 
•00433 
- -00002 
64-17 
■00404 
•00401 
- -00003 
72-57 
•00373 
•00370 
- -00003 
80-18 
•00348 
•00346 
- -00002 
87-93 
•00323 
•00323 
•00000 
Allyl Bromide. :CB . CHaBr. 
Prepared by Mr. J. G. Saltmarsh, Assoc. Pv.C.S., by Grosheintz’s method (‘Bulletin 
de la Soc. Chim. de Paris/ 30, 98). After drying and distillation the liquid boiled 
between 69°-58 and 70°-28. Bar. 745-7 millims. Corrected and reduced b.p. = 70°-5. 
Vapour density ; 
Found, I. 59-40; II. 59-11 ; Calculated, 60-40. 
The mercury in both cases was found to be slightly attacked by the vapoui of the 
allyl bromide. 
The observations for viscosity gave :— 
