154 REPORT—1896. 
For the present a second proposition is 
Proposition I1.—The amount of heat required to raise the tempera- 
ture of 1 gramme of water 1° C. of the scale of the hydrogen ther- 
mometer, at a mean temperature which may be taken as 10° C. of that 
thermometer, is 4°2 Joules. 
If further research should show that the statement in II. is not exact, 
the definition could be adjusted by a small alteration in the mean tem- 
perature at which the rise of 1° takes place. The definition in I. and 
the number (4°2) of Joules in a Calorie would remain unaltered. 
In Appendix II. a table is given showing the capacity for heat of 
water between 10° C. and 20° C., and in Appendix III. the values of the 
total heat of water has been calculated by Mr. Shaw from his experiments 
of Regnault and Rowland. 
Professor J. V. Jones has, during the year, calculated the correction 
to be applied to the value of the international ohm in absolute measure 
given by him at the Oxford meeting (1894), in consequence of the ellipticity 
of the standard coil used in his experiments. The required correction is 
00684 per cent., and the corrected value of the international ohm is 
*99983 x 10° absolute units. 
In conclusion the Committee recommend that they be reappointed, 
with a grant of 5/.; that Professor G. Carey Foster be chairman, and 
Mr. R. T. Glazebrook secretary. 
APPENDIX I. 
Extracts FROM LETTERS RECEIVED, DEALING WITH THE QUESTION OF 
THE Unit or Heat. 
1.—From Dr. C. Dieterici, Professor of Physics, Hanover. 
[This reply has, since it was sent to Mr. Griffiths, been printed in full in 
Wiedemann’s Annalen for February 1896. It is therefore not thought necessary 
to print it again here. ] 
2.—I’rom Dr. Dorn, Professor of Physics, Halle, 
December 27, 1895. 
[TRANSLATION. | 
. . . I quite agree with you that it is very necessary there should be 
an improvement in the department of calorimetry, and that the first step 
must be the determination of sharply defined units. I agree with you 
in the opinion that the new unit ought not to differ in a marked degree 
from the present, for it would otherwise cause great inconvenience to 
both physicists and chemists, and there would be no hope of introducing 
the new unit technically, 
I have really no objection to offer to the thermal unit being 42 x 10° 
ergs (or rather 41-89 x 10° ergs). 
3.—From Dr. W. Ostwald, Professor of Chemistry, Leipzig, 
February 12, 1896. 
[TRANSLATION. ] 
I entirely agree with your proposal to take some multiple of the erg 
as unit of heat. Such a step seems to me so undoubtedly necessary that, 
in my opinion, the question is when and not if such a change should be 
