646 MESSRS. T. E. THORPE AND J. W. RODGER OR THE RELATIONS 
The following tables show the numbers calculated by means of these constants, 
together with those actually observed ;— 
Molecular Viscosity at Slope ‘0^323. 
Observed. 
Calculated. 
Difference 
per cent. 
Pentane . 
G87 
689 
-0-3 i 
Hexane. 
818 
809 
IT ' 
Heptane. 
931 
929 
0-2 ! 
Octane. 
1035 
1049 
- 1-3 ! 
Isopentane. 
663 
668 
- 0-7 
Isohexane . 
799 
788 
1-4 ; 
Isoheptane . 
908 
908 
0-0 
Isoprene . 
620 
607 
2T 
Diallyl. 
728 
729 
- OT 
Methyl iodide. 
638 
664 
- 4-0 
Ethyl iodide. 
778 
784 
~ 0-8 
Propyl iodide. 
903 
904 
- OT 
Isopropyl iodide. 
878 
883 
- 0-6 
Isobutyl iodide. 
1010 
1003 
07 
Allyl iodide. 
864 
866 
- 0-2 
Ethyl bromide. 
663 
657 
0-9 
Propyl bromide. 
774 
777 
- 0-4 
Isopropyl bromide. 
750 
756 
- 0-8 ^ 
Isobutyl bromide. 
877 
876 
OT i 
1 
Allyl bromide. 
734 
739 
- 0-7 
Ethylene bromide. 
973 
962 
IT 
Propylene bromide. 
1068 
1082 
- 1-3 
Isobutylene bromide .... 
1171 
1181 
- 0-9 ! 
Acetylene bromide. 
932 
921 
1-2 ; 
Propyl chloride. 
658 
661 
- 0-4 
Isopi’opyl chloride. 
644 
640 
0-6 
Isobutyl chloride. 
760 
760 
0-0 : 
Allyl chloride. 
617 
623 
- 1-0 
Ethylene chloride. 
737 
728 
1-2 : 
Methylene chloride. 
600 
600 
0-0 
Methyl sulphide. 
578 
575 
0-5 
Ethyl sulphide. 
812 
815 
- 0-3 
