266 
DR. J. YOUNG AND PROFESSOR G. FORBES ON THE 
January 20, 1881, No. 6. 
Wheel. 
Clock. 
Beading. 
Differences. 
At mean reading. 
Beading. 
Alternate 
differences. 
Alternate second 
differences. 
231 
2,642 
7,449 
2,411 
2,404 
1,437 
5,046 
515 
9,890 
23,072 
32,309 
45,300 
54,433 
22,557 
(22,419) 
22,228 
22,124 
329 
295 
Signal at 2,406 
Signal at 24,108 
+=•002406 
7=21,141 
4/= 331 
v= 1-1210 
Correction for friction, &c. =— -0022 
v= 1-1188 
+=-,=465-00 
+ 
January 20, 1881, No. 7. 
Wheel. 
Clock. 
Beading. 
Differences. 
At mean reading. 
Beading. 
Alternate 
differences. 
Alternate second 
differences. 
6,229 
8,610 
13,325 
2,381 
2,358 
7,420 
10,968 
4,722 
18,357 
27,994 
41,379 
50,908 
64,095 
23,272 
(23,022) 
22,914 
22,716 
358 
306 
Signal at 9,144 
Signal at 29,346 
+=•002370 
7=29,912 
4/= 352 
v= 1-1511 
Correction for friction, &c. = + -0004 
v= 1-1515 
+'=-,=485-87 
+ 
i 
l 
2m 
(+++') P B 
r+1 
+ 
g+p 
186,572 
1-00138 
Product =V= 186,830 
0 
From Nos. 6 and 7 
y Correction for second term = +258. 
