905 
number of points in the range between hydrogen and oxygen tempe- 
ratures, and these values were then smoothed graphically in the 
dW/dT-tigure. 
Together with the gold wire we accurately calibrated each time 
the constantin wire which was to serve for the heating, in order 
that this wire might serve as thermometer also (cf. p. 904 note 2) in 
case the gold wire should become defective. The corresponding data 
are given in Comm. N°. 142a § 4d and in this paper table I. 
§ 4. Heat capacity of the core. This was measured separately in 
TABLE II. 
Heat capacity of the core Ky 
No. : | Mean | Increase of | _Heat capacity 
temperature | temperature in Joules / degree 
10 June II (see tc) Ke | 0.763 | 0.727 
Ill | 15.28 ee ee 0.785, 
IV 16.19 0.992 0.887 
Team Ey Be le a aed 1.019 
| VI © | 18,285 0.964 | 1.155 
Det IG. Tie 0.867 1.288 
| EE TED oe |) ~ A 1.530 
VIII 20.16 Wee ee 1.406 
IX 21.13 0.938 1.565 
X*1) | 28.375 0.979 2.99 
| XP | 29.00 0.927 3.17 
| XIL | 36.40 0.675 5.04 
| XIII | 46.32 0.509 8.19 
13 June II* | 61.87 0.503 | 12.91 | 
Hr | 62.16 0.490 13.22 
IV | 70.33 0.429 15.39 
rn re ANN ET 15.58 
| I* 80.36 | 0.346 18.74 
| i4Junel 80.519 0.318 17.87 
I | 80.88 | 0.356 18.56 
1) For the measurements marked by an * the calculation of the increase of 
60 
Proceedings Royal Acad. Amsterdam. Vol. XVII. 
