160 DR K. H. UKIFFITHS AND MR. EZER GRIFFITHS ON THE 



Explanation of the Tables. 



Column I. The temperature at which experiments were performed. 



During our experiments at C. we changed both thermometers and lids ; we have, 

 therefore, in this column indicated the thermometers and lid used. 



Letters AA and AA', indicate the thermometers referred to in Section III. 



Letters L,, the lighter, and L,, the heavier lid (see Section VI.). 



Where no indication is given, the thermometer used was AA', and lid, L a . 



Column II. The dates on which the series were performed is given to indicate the 

 results obtained on repetition after lapse of time. 



Column III. The number of transits denotes the number of observations of $8/St 

 obtained during the experiment. 



Column IV. No. Cd Cells. The number of standard Weston cells in series, whose 

 E.M.F. was balanced at the ends of the heating coil. 



Column V. " Rise Above." This was determined at the close of each experiment. 



The line representing an experiment was shifted horizontally by this amount. 



1 <W 

 Column VI. Tangents (Abscissae 0'l Pt). The slope of the line -j- with tempe- 



IV 0*' 



rature H as abscissa. 



Absolute value = number in Column x 10~ 9 . 



Column VII. 'The points of intersection of the lines of various rates with the 

 ordinate through N (see p. 158). 



Absolute value = number in Column x 10~ 9 . 



Column VIII. The probable observational error per cent, of the group. 



Column IX. The data required for the reduction. It will be noticed that the 

 mass of the metal block has in some cases changed during the course of the experi- 

 ment, owing to certain alterations such as enlarging holes, &c., which were found 

 necessary. 



ms denotes the capacity for heat of copper case and the group of subsidiary 

 substances, or of the latter only when the block itself is copper. 



