338 MR. E. H. GRIFFITHS ON THE LATENT 
If we assume the capacity as 1°6, we cannot be greatly in error, and this quantity 
must be subtracted from the values of W, (supra) for all experiments after No. 3. 
Now the values of C,, from Experiments II. and IV. differ by 1:89. This apparent 
difference of ‘3 in the results has, however, to be further diminished. On September 14, 
I found it necessary to withdraw thermometer AB from the calorimeter. Before 
doing so, I weighed a “ weighing bottle” containing a roll of blotting-paper, and on 
removing the thermometer, I wiped its stem and bulb with this paper in order to find 
the weight of oil withdrawn, which proved to be -104 gram. Hence the differences 
in Column VI. of the next Table. 
TaBLE XX V.—-Specific Heat of Oil. 







| 
II. III. VI. 
I, 5 | IV. V. 6 VIL. 
Experiment. eee 3 oe | W, (supra). || Cap. of oil. laee Zl Sy. 
IIt. 50°024. 324-74 83°39 241-35 474-12 5090 
II. 40°122 319-74 82:20 23754 47412 5008 
VEC 40°142 31788 | 80:60* 237-28 474-024 5005 
ile 31-996 31487 81-14 233°73 474-12 “4930 
Vv. 29-979 312-41 79°30* 23311 474:02+ 4917 
VI. 29:998 |  312:35 79°30* 233°05 474:02+ ‘4916 
VII. 20:031 | 307°50 78:51* 228:99 474-02+ “4830 






Appendix IIJ.—Derains oF DETERMINATION oF R,. 
In Paper J., p. 409, is given a table showing the errors of all the individual coils in 
my dial resistance box. These errors were, by kind permission of Mr. GLAZEBROOK, 
ascertained by direct comparison with the B.A. standards. 
T extract the following from the remarks on that table (p. 410, cbzd.) : 
‘A table was constructed giving the total difference between the reading and the 
real value (in terms of ‘‘ legal ohms”) for every position of the plugs in each dial. 
This difference we termed the “plug correction.”{ Having made this correction, we 
had then to correct for any maccuracy in the ratio arms of the bridge, and as all 
determinations of the calorimeter coil resistance were made with 1000 (right) and 
10 (left) as the arms, it is only necessary to here give the correction for those coils. 
“ Now 
10L/1000R = 9:9977/1000-30 = 0:0099947.§ 
* After removal of thermometer Go. 
+ After remoyal of ‘10 gram oil. 
+ The correction for the temperature of the coils was made before applying the “ plug correction.” 
§ There is here a mistake in Paper J. This was corrected in a subsequent communication, ‘ Proc, 
Roy. Soc.,’ vol. 55, p. 25. 
