668 PROFESSOR THOMSON ON THE ELECTRO-DYNAMIC QUALITIES OF METALS. 
46. Another experiment was also made on the new iron conductor, and results as 
decisive as those in the first two experiments were obtained. The following abridged 
Table shows sufficiently the character of the effect demonstrated ; and the analysis of 
the progress of variation is given in the full table (Table III. § 47) below. 
Experiment VI. December 2, 1853. 
Conductor composed of thirty slips of sheet iron. 
Periods. 
(Current six times eight minutes in 
differences of temperature after e 
By end next A. 
each direction.) Temperatures and 
ight minutes of current entering 
By end next B. 
Augmentations 
of differences 
from middles to 
ends of periods. 
Ta- 
Tb- 
Tb-Ta=D. 
Ta- 
Tb- 
Tb-Ta=D'. 
D'-D. 
I. 
54-76 
56-33 
0 
1-57 
5°4-80 
56-66 
1-86 
°-29 
II. 
III. 
IV. 
V. 
VI. 
54- 97 
55- 01 
55-22 
55-31 
55-12 
56-68 
56-70 
56- 90 
57- 08 
57-00 
1-71 
1-69 
1-68 
1-77 
1-88 
54-89 
54- 93 
55- 08 
55-07 
54-84 
56-80 
56- 86 
57- 10 
57-12 
57-03 
1-91 
1- 93 
2- 02 
2-05 
2-19 
-20 
-24 
-34 
-28 
-31 
Means for five periods 
55-126 
56-872 
1-746 
54-962 
56-982 
2-020 
-274 
Augmentation of differenceTg — T^during included periods -33 
Deduct average augmentation per half-period -033 
Effect due to reversal of current 0°-241, 
in favour of Resinous Electricity. 
47 . The following Tables show the progress of variation of the difference between 
the temperatures of the two tested localities (A, B) of the iron conductor, during 
each of the three regular experiments referred to above, as derived directly from 
the quarter-minute or half-minute observations actually made in the course of each 
experiment. 
only irregular fluctuations, sometimes counteracting and reversing the true effect, but generally only diminish- 
ing it and increasing it alternately, and always maintaining, during the whole latter half of the aggregate of 
the half-periods, an average deviation of the kind noted as the final result. A careful consideration of the 
Tables I., II. and III. given below, § 56, for the copper conductor and of their graphical representation (see 
Diagram, § 57), is, I think, sufficient to establish this view. [April 9, 1856.] 
