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Proceedings of the Boyal Society 
heart by the ligature which was applied whilst some blood remained 
in the organ ; whilst in the second case the tension was kept up, 
irregularly and intermittently, by means of the “Higginson” syringe, 
and by stopping the outflow of the fluid at the various points in 
turn. (2) Whilst both pigs were diseased, the lesions were more 
pronounced in the viscera of the second animal, and the vitality of 
the tissues might be expected to be somewhat lower. 
The points to be specially noted in the second case are — (a) that, 
contrary to what is usually observed, movements were arrested in 
the right auricle before those in the left had ceased ; (b) that the 
contraction of the superior vena cava was quite independent of that 
of the auricle, a contraction occurring before each contraction of 
the auricle. 
The latter observation coincides with those quoted from Haller 
andbTysten by Landois, toe. cit., p. 69: — “Independent rhythmical 
contractions of the venae cavse and pulmonary veins are often noticed 
after the heart has ceased to beat.” 
Stirling also notes that such contractions can be observed in the 
veins of the rabbit after the heart is cut out of the body. 
The contraction of the superior vena cava was so distinct and 
forcible that it suggested to us the idea that it might, under certain 
conditions, be sufficient to produce a distinct sound which might be 
referred to the orifice. 
It is interesting to note, in connection with this contraction, that 
we were able to trace striped muscular fibre in the wall of the 
superior vena cava at least 1J inch from the orifice. 
7. On the Heats of Combination of Zinc and Iodine in 
Presence of Water, as determined by the Measurement 
of the Electromotive Eorce of the Zinc-Iodine Cell. By 
A. P. Laurie, Esq., B.A., B.Sc. 
During the spring of 1882 Mr Burton and I communicated some 
preliminary experiments on a new method of measuring the heats 
of combination of the metals with the halogens.* 
In this paper I propose to show the result of the application of 
Proceedings of R.S.E., 1881 - 82 . 
