( 55S. ) 
If from this formula for the variation of latitude for Leyden we 
want tc deduce that for the variation of latitude for Greenwich, we 
must only take for the date of the maximum latitude 5 days earlier 
i. e. April 21st 1888, so that the co-ordinates of the motion of the 
pole for Greenwich are : 
12410749 
2 = + 0".136 cos An —____—_ 
430.65 
t— 2410749 
y = — 0".136 sin 2% ——____ 
430.66 
in which t represents the Julian date. 
11. If we compare this epoch for the maximum latitude of 
Greenwich with that deduced by Dr. E. F. v. p. S. BAKHUYZEN, 
we see a difference of 2181 and after subtracting 5 periods or 2153 
days, it appears that the epoch found by me occurs 28 days later 
than that according to Dr. E. F. v. p. S. BAKHUYZEN. . 
In the Astronomische Nachrichten n° 3207 A. SOKOLOFF has 
given the results of an investigation of the motion of the pole ina 
period of 430 days by means of the meridian marks of the transit- 
instrument in the observatory at Pulkowa. In order to compare his 
results with those found by me, I here give the results deduced by 
SOKOLOFF from the observations from 1880—1887 made by WAGNER, 
WrirrraM and HARZER. 
a. From 476 transits of @ Ursae-Minoris 
Amplitude = 0".172 
Epoch for Greenwich = 2410743 
i.e. 22 days later than according to HK. F. v. v.58. B. 
b. From 288 transits of 0 Ursae-Minoris: 
Amplitude = 0".195 
Epoch for Greenwich = 2410771 
i.e. 50 days later than according to E. F. v. v. 5. B. 
ce. From 226 transits of 51 H. Cephei: 
Amplitude = 0".156 
Epoch for Greenwich = 2410759 
i.e. 38 days later than according to E. F. v. D. 8. B. 
In SoxoLorr’s computation the time of the period is assumed to 
be 429.7 days. The epoch of maximum latitude of Greenwich given 
above, has been reduced by me from the year 1884 to the year 
1888 by using a period of 430.66 days. 
