308 Proceedings of the lioyal Society 
The following Gentleman was elected a Fellow of the 
Society :— 
John Auld, Esq., W.S. 
Monday , 19 th December 1870. 
Dr CHRISTISON, President, in the Chair. 
The following Communications were read :— 
1. Additional Remarks on the Theory of Capillary 
Attraction. By Edward Sang, Esq. 
2. Laboratory Notes : On Thermo-Electricity. 
By Professor Tait. 
In a paper presented to the Society in 1867-8 I deduced from 
certain hypothetical considerations regarding Dissipation of Energy 
results connected with the thermal and electric conductivity of 
bodies, the electric convection of heat, &c. As these were all of a 
confessedly somewhat speculative character, I printed at the time 
only that connected with thermal conductivity, which I had the 
means of comparing with experiment, and which seemed to accord 
fairly with Forbes’ experimental results. But the assumption on 
which this was based was essentially involved in all the other por¬ 
tions of the paper. 
With a view to the testing of my hypothetical result as to electric 
convection of heat, several of my students, especially Messrs May 
and Straker, last summer made a careful determination of the elec¬ 
tromotive force in various thermo-electric circuits through wide 
ranges of temperature. Their results for a standard iron-wire, 
connected successively with two very different specimens of copper, 
when plotted, showed curves so closely resembling parabolas that 1 
was led to look over my former investigations and determine what, 
on my hypothetical reasoning, the curves should be. This I had 
entirely omitted to do. I easily found that the parabola ought, on 
my hypothesis, to be the curve in every case, and I made last 
August a numerous and careful set of determinations with Ivew 
standard mercurial thermometers as an additional verification. 
