90 
Differences in centenn. proper motion N. F. K.—Newcomb 1900 
SS 
| 
| Au, | Aus 
| | 
J +10°—+ 15° | —0%0057 | —0/105 
S+15°-—4+20° | 40.0154 | +0.060 
d+ 20°—+425° | 40.0003 | 0.254 
JS + 30°— + 35° —+0.0028 +0.210 
The values of Ag, and Au, were smoothed by formulae of the 
form: 
Au, =a -- 6d 
Aus =a + b'd 
this is advisable as the zone-positions are based upon fundamental 
stars some of which liefoutside the zones. I found: 
a = + 080010 6 = + 00001 
a = — 0"216 6 == 01015 
and with this the smoothed values 
Au, Aus 
+0°002 | —0703 
+0.003 | +0.05 
49.003 9.12 
+0.004 | 10.27 
These values are subtracted from the differences for each star. 
From ‚the residual values 2-hour-groups according to R.A. were 
formed for the four declination-groups together. 
In the following table are collected the mean values for the two- 
hour-groups, where Ob represents the group from R.A. 23! to 1) etc. 
Dirrerences N.F.K, — NEWCOMB DEPENDENT UPON THE A.R. 
a Au, Au; Stars 
Ok 405.004 2 220144 46 
2 = aa der A'2 7 
4 S004 + .03 16 
BE 000 sore MD 
8 et OÙ en a 9 
10g) rele OO ee OE 
