XX PRELIMINARY GENERAL CATALOGUE OF STARS FOR 1900 
in touch with the scale of the Uranometria Nova and Bonner Durchmusterung with 
some reference to the historic 9^0, which through the estimates of Bessel, Argelander, 
and others had also come to have a fairly definite (though not absolutely rigorous) 
meaning to the great body of astronomers. 
It is to be hoped that Dr. Chandler, at some future time, will give an exposition 
of the methods by which he has reached results of such great importance and value. 
Meanwhile, in view of the most liberal and generous authorization of Dr. Chandler, 
his normal system may best be defined here through some of his tables of systematic 
corrections. The logarithm of the ratio of brightness for one magnitude in Chan¬ 
dler’s Normal Uranometry is stated by him to be .36, differing from Pogson’s scale 
(log. ratio = .4) now in extensive use. As will appear, Chandler’s system is nearly 
equivalent to the Potsdam system for “GW” (yellowish white) stars plus .08 (M 
— 6^0), where M indicates the normal magnitude of a given star. It will be noted 
that Dr. Chandler deduces decided systematic corrections on account of color. 
Adopted Corrections to Potsdam Photometry. 
Adopted Corrections to Harvard Photometry. 
(Argument 
is corrected or normal magnitude.) 
(Vols. XLIV and XLV and approximately so for others.) 
Normal. 
w 
GW 
WG 
G 
RG 
Normal. 
w 
GW 
WG 
G 
RG 
M 
M 
M 
M 
M 
M 
M 
M 
M 
M 
M 
M 
2.0 
— .46 
- -43 
- -39 
- -35 
- -37 
2.0 
- -15 
- .18 
“ -23 
- .27 
- .27 
3-0 
-•33 
- .29 
— .24 
- -19 
— .l8 
3 -o 
— .06 
- .09 
— .14 
— .l8 
- .18 
4.0 
— .22 
- .18 
- .11 
- -°5 
— .02 
4.0 
+ .05 
+ .02 
~ -03 
- .07 
-.07 
5 -° 
~ - r 3 
- .08 
.00 
+ .07 
+ -12 
5 -o 
+ •17 
+ .14 
+ .09 
+ .05 
+ .05 
6.0 
-.07 
— .02 
-f- .08 
-I- .16 
+ -23 
6.0 
+ -31 
.28 
+ -23 
+ .19 
+ .19 
7.0 
- -°3 
+ .02 
+ -13 
+ -2 3 
+ - 3 2 
7.0 
+ .42 
+ •39 
+ -34 
+ - 3 1 
+ - 3 ° 
The arguments for color, “ W,” “ GW,” etc., have the meanings attached to them 
in the Potsdam Photometry: white, yellowish white, whitish yellow, yellow, and 
reddish yellow, respectively. 
For those of the Harvard series published in Volumes XIV, XXIV, XXXIV, and 
XLVI, Dr. Chandler deduces corrections periodic with right-ascension additional 
to the corrections for scale already given for Volumes XLIV and XLV. 
Special Corrections applicable to Harvard Photometry. 
RA 
Vol. XIV 
XXIV 
XXXIV 
XLVI 
RA 
Vol. XIV 
XXIV 
XXXIV 
XLVI 
h 
M 
M 
M 
M 
h 
M 
M 
M 
M 
O 
— .02 
- .08 
+ .06 
- -07 
12 
— .OI 
+ .01 
- .07 
- .09 
I 
— .01 
— .09 
4 - .08 
- .07 
13 
- .04 
— .01 
- .07 
- .09 
2 
+ .01 
— .08 
-f .08 
— .06 
14 
— .06 
— .02 
— .06 
- .09 
3 
+ .02 
- -07 
+ .06 
- -05 
is 
— .06 
— .04 
- .07 
— .11 
4 
+ .04 
- .05 
+ .02 
- .04 
16 
— .06 
- -05 
- -°7 
- -13 
5 
+ .05 
— .04 
— .02 
- .03 
17 
— .06 
— .06 
— .08 
- .14 
6 
“f“ .06 
— .02 
- -07 
+ .04 
18 
— .06 
— .06 
- .08 
— .16 
7 
+ .06 
.00 
- .09 
— .06 
19 
— .06 
— .04 
- .07 
— -14 
8 
+ .06 
+ .02 
— .10 
- .09 
20 
- -05 
— .04 
— .06 
— .12 
9 
+ -05 
+ .02 
- .09 
— .11 
21 
- -°5 
- .04 
- -05 
— .11 
10 
+ .04 
+ -03 
- .09 
— .12 
22 
- .04 
- -05 
- .03 
- .09 
11 
+ .02 
+ .02 
— .08 
— .11 
23 
- .03 
- .07 
+ .01 
— .08 
