456 
MESSRS. T. E. THORPE AND J. W. RODGER ON THE RELATIONS 
Jii reducing the observations we have adopted (15715°)= 0’6633 (which gives 
d{0°/4°) ■-= 0’6766) (Perkin, ‘Chem. Soc. Trans.,’ 1884, 447) for the relative 
density, and the expression 
V = 1 -p *03137022^ -H -0697649^^ + -0729819^3 
(Thorpe and Jones, loc. cit.) for the thermal expansion. 
Taking 
■002817 
26°-43, 
we get 
_ 917-96 
~ (209-35 + t) 2-S237 ’ 
rj^ = ‘003688 
h = 0°-61 
1'6 
•002151 
^3 = 55°-43 
r ).2 (calculated) = 
t .2 (from curve) = 
which gives values in close agreement with those obtained by observation 
Mean temp. 
V- 
Difference. 
Observed (mean). 
Calculated. 
0 
0-61 
-003688 
•003688 
•000000 
5-59 
-003487 
•003493 
+ -000006 
10-25 
-003316 
•003323 
+ -000007 
15-26 
■003147 
•003153 
+ -000006 
20-51 
■002987 
•002988 
+ -000001 
25-45 
■002841 
•002844 
+ -000003 
31-97 
■002670 
•002669 
- -000001 
3G-63 
•002550 
■002553 
+ -000003 
41-07 
•002450 
•002449 
- -000001 
45-38 
•002355 
•002354 
- -000001 
51-17 
■002235 
•002234 
- -000001 
55-43 
•002151 
•002151 
•000000 
Heptane, CH3.(CH3)5.CH3, 
A specimen of pure normal heptane, from Pinus Sahiniana, was distilled from sodium 
wire. It boiled at 98°'4 (corrected and reduced). 
Determination of vapour density :— 
1 . II. 
Found.50‘11 50‘19. 
Calculated .... 50"00 
Observations for viscosity gave :— 
