306 W.A. Rogers on Variability of Personal Equation. 
ten to fifteen seconds, and the last seven by an interval varying 
between two and three seconds. 
R—T. 4 
Mean of the first three wires. Mean of the last seven wires. 
fay 26 ——201* : 
June 2 80 075 
4 086 088 
"187 059 
16 116 052 
17 "155 091 
22 “to2 051 
26 {22 064 
Differences. 
May 26 ——’ 1335 
June 2 05 
“000 
9 "128 Mean ——’069° 
Is 064 
17 064 
22 "101 
26 "053 
While these differences do not agree well with each other 
they all have the same sign. The disacreement is without 
doubt partly due to certain local disturbances on some of the 
wires, which will be noticed under the next head. 
V.—Does the shape of the stars observed affect the personal equa 
tion ? ane 
erences did not occur in the values R.—B. , it is evident er 
oe vestigation with the following inquiry: 
Does the relative equation deri: et in 
mS ste ete rived from artificial stars agree 
we eal a derived fom acta bseretons sth he 
—,, +, J 18 af important one; for if this agreement” 
ound to exist, it will then be easy to free longitude from the 
