a2 > Mr. 8. C. Laws on the Thomson Effect 
It will be observed that these values of o are about 
15 times as large as those given for bismuth; the largest 
value given by Wiedemann ®* is for an alloy of bismuth and 
antimony, and is about 2°3 times as large as that given for 
bismuth, so that the specific heat of electricity in this alloy is 
about six times greater than that found for any substance 
previously examined. 
VIL. EHeperiments with Alloy No. 2. 
Analyses of this alloy showed that it contained 3°01 per 
cent. tin. 
Mean diameter of rods = 4°973 mm. 
Mean resistance of rods = 0:000177 ohm per mm. 
Hxamples of observations made with this alloy are shown 
in Tables V. and VI. 
TasBLE V.—Thomson Effect. 









© = 3 amperes. 2, = 6:1 cme: 0 = O43. 
Let — 10) ay eS = 0°62 degree per mm. 
rat rl See Sek tM | 
Ay ey 10: yx 107. é. 
14 —4°32 
3°0 +6°33 10°10 
4°56 —3°21 
ee +6'80 9°86 
9:2 — 2°92 
12-19 —3'94 
2°13 +649 10-11 
4-13 — 5°29 
oy +6°52 9°82 
88 | —33l 9°92 
10-4 +671 
a een i 
Mean value for 0... 9°96 
Correction ... “06 
0; wae) OeOO) 
TABLE VI.—Joule Effect. 
C = 2 amperes. ae = 6 lems, ts —= O20 ems, 









H. ep Oe yp dx LO? 0» 
11°29 —7:26 
1-11 +811 LoS 
3:0 — 7:07 
4°52 +8°60 15°7 
6°50 —7:08 
8:42 | +8'44 15°5 
10°53 —6°99 
Mean value for Slee 155. 

* Wiedemann, Electricitat, Band ii. p. 430. 


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