332 
PROFESSOR TYNDALL’S CONTRIBUTIONS TO MOLECULAR PHYSICS. 
Table I. (continued). 
Name of liquid. 
Deflection. 
Absorption per 100. 
Benzol ..... 
. . . 35-3 
67-0 
Amylene .... 
. . . 37-7 
74-8 
Sulphuric Ether . . 
. . . 39-0 
79-4 
Acetic Ether . 
. . . 39-6 
81-6 
Alcohol .... 
. . . 41-0 
86-6 
Water* .... 
. . . 43-3 
91*4 
Total heat .... 
. . . 44-2 
100 
In these experiments I employed a 
less delicate galvanometer than that used in my 
former researches. The experiments 
were made on the 29th of September, and on the 
following day I repeated them with the following results 
Table II. — Radiation of heat through Liquids. Source of heat, red-hot platinum spiral. 
Thickness of liquid layer (H)7 of an 
inch. 
Name of liquid. 
Deflection. 
Absorption per 100. 
Iodide of Methyl 
. . . 33-5 
53-7 
Iodide of Ethyl . 
. . . 35-5 
58-7 
Benzol 
. . . 37-5 
64-4 
Amylene .... 
. . . 39-5 . 
70-7 
Sulphuric Ether . 
. . . 41-0 
75-4 
Acetic Ether . . . 
. . . 41-5 
76-9 
Formic Ether . . . 
. . . 42-4 
80-0 
Alcohol 
. . . 43-5 
84-2 
Water 
. . . 44-7 
90-5 
Total heat .... 
. . . 46-7 
100-0 
On the 28th of October my most delicate galvanometer was at liberty, and with it I 
executed the experiments performed with the coarser one. The following are the 
results : — 
Table III. — Radiation of heat through Liquids. Source, red-hot platinum spiral. 
Thickness of liquid layer 0-07 of an inch. 
Name of liquid. 
Deflection. 
Absorption per 100. 
Bisulphide of Carbon 
O 
. 9-0 
12-5 
Chloroform 
. 25-2 
35-0 
Iodide of Methyl 
. 36-0 
53-2 
54-3 
Ditto, strongly coloured with iodine . 
. 36-0 
53-2 
Iodide of Ethyl 
. 38-2 
59-0 
59-6 
* To prevent the water from attacking the cell, it was always first saturated with the substance of the cell 
itself, namely, transparent rock-salt. 
