152 
ANNUAL, REPORT SMITHSONIAN INSTITUTION, 1919. 
The agreement in the scale values obtained from x and y is satis- 
factory. There appears to be a small difference in the orientations 
as derived from the two directions in the comparison plates. This 
is, however, of small importance in the determination of a. There 
is a difference of scale value from July 15-18 shown in both coordi- 
nates. For the purpose of exhibiting the gravitational displace- 
ments residuals have been computed using adopted values for the 
scale and orientation given above along with the calculated correc- 
tions for differential refraction and aberration. This has the ad- 
vantage of reducing the number of constants employed in the reduc- 
tion of the plates and lessens the possibility of masking any dis- 
cordances, though greater irregularities necessarily appear when four 
arbitrary constants instead of six are used in the reduction of each 
plate. The quantities are converted from revolutions to seconds of 
arc, as the more familiar unit facilitates judgment of the results. 
Table VIII. — Comi)arison of the Eclipse and comparison photographs with the 
scale plate after correction for diffej'ential refraction and aberration, orien- 
tation, and change of scale. 
ECLIPSE PLATES, RIGHT ASCENSION. 
No. of star. 
I. 
II. 
III. 
IV. 
V. 
VII. 
VIII. 
Mean. 
11 
-0.18 
- .45 
+ .08 
- .23 
- .14 
+ .17 
+ .75 
-0.51 
- .81 
+ .11 
- .11 
+ .23 
+ .06 
+ 1.03 
-0.46 
- .38 
- .08 
- .19 
- .09 
+ .14 
+ 1.06 
-0.07 
- .58 
- .11 
- .05 
- .11 
- .18 
+ 1.09 
-0.04 
- .60 
- .11 
- .02 
- .13 
- .11 
+ 1.01 
-0.72 
- .38 
- .16 
- .02 
+ .13 
+ .14 
+ .98 
-0.43 
- .62 
- .18 
- .01 
- .08 
- .01 
+ 1.30 
-0.34 
5 
- .54 
4 
- .00 
3 
- .09 
6 
- .03 
10 
+ .03 
2 
+ 1.03 
ECLIPSE PLATES, DECLINATION. 
0.00 
- .00 
-0.03 
+0.02 
+ 0.17 
+0.16 
+0.01 
- .38 
- .54 
- .61 
- .30 
- .39 
- .73 
- .81 
+1.19 
+ 1.04 
+ 1.03 
+ .98 
+ 1.11 
+ 1.19 
+ 1.24 
+ 1.42 
+ 1.58 
+1.50 
+1.39 
+1.55 
+ 1.49 
+ 1.49 
+ .65 
+ .79 
+ 1.01 
+ .97 
+ .71 
+ .95 
+ 1.01 
+ .62 
+ .46 
+ 1.03 
+ .54 
+ .56 
+ .58 
+ .74 
+ .01 
+ .25 
- .40 
- .09 
- .22 
- .14 
- .17 
+0.03 
- .54 
+1.11 
+1.49 
+ .87 
+ .65 
- .11 
COMPARISON PLATES 
, RIGHT ASCENSION. 
14sa. 
1426. 
15i. 
152. 
17i. 
172. 
I82. 
Mean. 
11 
-0.19 
- .42 
- .01 
+ .14 
+ .02 
+ .17 
+ .31 
-0. 24 
+ .16 
+ .03 
+ .09 
- .18 
- .06 
+ .18 
-0.23 
- .36 
- .01 
+ .28 
+ .26 
+ .20 
- .16 
-0.28 
- .32 
+ .05 
+ .10 
+ .06 
+ .18 
+ .22 
+0.11 
- .24 
- .04 
- .03 
+ .13 
+ .13 
- .04 
-0.19 
- .33 
+ .23 
+ .21 
+ .03 
- .02 
+ .08 
-0.02 
- .26 
+ .08 
- .01 
+ .14 
+ .15 
- .06 
—0.15 
6 
- .25 
4 
+ .05 
3 
+ .11 
6 
+ .07 
10 
+ .11 
2 
+ .08 
