404 ME. W. HOPKIXS OX THE COXSTEUCTIOX OF A XEW CALOEDIETEE 
is required, such as is investigated in that article. Its amount is the same in all the 
experiments. Hence, on account of this con-ection, we have 
Q*=(K,-E,){l+f| (art. 10). 
= l'33{l + ‘038} in series IV. 
=2’94{I + -038} in series Y. 
=5’10{l4-‘038} in series VI. 
Taking the sum of these two con’ections in each series respectively, 
Q“= 1-33(1 -06 9) = 1-42 in series IV. 
Q‘’=2-94(l-066)=3-13 in series V. 
Q«= 5-10(1 -060) = 5-41 in series VI. 
These are the corrected values which are to he substituted for Q in the formula (9.). 
After the requisite numerical calculation, we thus obtain the following thi-ee values of A : 
A= 1-781 from series IV. 
A= 1-420 from series V. 
A=1'444 from series VI. 
Mean value =1-548. 
It will be observed that the first of these values of A is considerably larger than the 
two others. It is that which corresponds to the smallest value of the difference of tem- 
perature denoted by or — Hi, and small values of this quantity are imfavoiu-able for 
the accurate determination of A, since, in such case, a small error in the experimental 
result will lead to a considerable error in the A alue of A. The above mean value, 1-548, 
is probably too large, and I should rather adopt 1-5 as a more probable value, thus 
giving greater weight to the two last determinations than to the first. The formula (9.) 
then becomes 
Q = 1 -500 1)+ -00648 (10.) 
Comparing the values of Q obtained from this formula, with the values of — H, as 
corrected above, we have the following results : — 
Comparison of the Observed and Calculated Values of Q for Bnj Chalk. 
Series of 
experiments. 
Values of 9 {€.). 
Values of f (C.). 
Calculated 
values of Q. 
Corrected observed 
values of Q. 
DitTei-eiices. j 
IV. 
O 
15-7 
41-66 
1*29 
1*42 
•13 i 
V. 
15*55 
85*70 
3*19 
3*13 
•06 1 
VI. 
15*75 
127-85 
5-46 
5-41 
*05 j 
17. Three similar series of experiments were made with a disc of Vc?c Sandstone. 
It will be sufficient, I conceive, to give the results without details, which are exactly 
