Measure of Resistance to Galvanic Currents. 33 
into a deviation to the right. By again slightly altering the 
position of the slide, the first movement to the left could be 
rendered so small as to be imperceptible, and the effect of the 
change of temperature could thereby be entirely obviated. 
Table IV. 
SCE ae | 1 | ed eg 3 
a. b. a. b. a. b. 
605°7 394:3 429-1 570-9| 456 543°7 
Observed resist-] | -...... | ...... 429-0 571:1) 456-3 543-6 
Ee wot ol ld sesame. t yoteton te shecias 456°2 543°3 
epee bee) aes MPR < souk ee ee 456°2 543°6 
Mean value ...... 605°7 =| 894°3:'429-05 571:0 456-2 543°6 
DAS eS eee 1-536) ...... | OP. 0°8392 
eke anade\cns es TO16-52 |... 2 AOR 2S. ol Been: 55°38 
W 
er POOB Ys .355 HOGS PEN 1-:0008 
WwW, | | 
Ma cas. 4. | 5 | 6 
a. De | a. | b. | a. | b. 
247-6 | 752-6 227-4 | 772-8) 633-2 | 366-8 
@bseeved resist- |} i... | vce. 227°3 772°8| 633°15 || 366-85 
AMES aceon fee P| ek cnos Proce raise «Web oidae 633°10 | 366-90 
Mean value ...... 247-6 | 752-6 227-35 | 7728 633:15 | 366-85 
Ne 0-329) ...... O20 42 eon 1:726 : 
VU Re ae eee ZVITEA askces 194°7 | ee 1142-3 
W 
he O99? sn eC So 1-005 
W, | ‘ 
The line distinguished by the letter W, is found from the pre- 
ceding one by multiplication by 661°8, which number was fur- 
nished by comparing the calculated resistance of tube 2 with 
that of the Jacobi’s standard employed. The numbers in this 
line ought therefore to agree with the resistances as derived from 
calculation contained in Table ILI. The numbers in the line 
headed ue , which are the ratios of the calculated and observed 
esistomees, show that these magnitudes do not differ more than 
was to be expected. The most considerable crrors in our mea- 
surements arose from the fact that neither the temperature of the 
mercury nor that of the copper standard was constant. The 
Phil, Mag. 8. 4. Vol. 21. No. 137. Jan. 1861 D 
