( 607 ) 
any atmospherical polarization was shown. This was however not 
found to any appreciable amount. 
Mr. vAN DER Escu has succeeded during totality in making com- 
plete measures on 11 points of the corona. The result is given in 
the following table. The position angles are counted from North 
through East; the radius of the moon is 13,5 mm. Fig. 1 shows 
the positions of the points chosen. The image of the moon and the 
aperture of the diaphragm, (1.1 mm)’, are drawn at their real size. 
The light admitted through this aperture was analyzed by a modified 
polarimeter of CoRNU, 
Reading of | Proportion of 
Nr, Position-angle. | Radius-vector. analyzer polarized light 
z | cos 2 «2 
1 218,°5 15 mm 38° 0,242 
2 218,5 20 o4 0,375 
3 145 14 31,5 0,259 
4 155,5 15 43 0,070 
5 136,5 22,5 45 0,000 
6 73,5 15 38 0,242 
7 73,5 20,5 49,9, 0,098 
8 73,5 22,5 45 0,000 
9 48 14 38,2 0,237 
10 48 18 34 0,375 
41 48 24 Ah 0,035 
It appears from these numbers that the light of the corona at a 
certain distance from the sun’s limb is more strongly polarized than 
in the neighbourhood of that limb. At still greater distances the 
polarization decreases again. That the observation Nr.4 has given 
a smaller proportion of polarized light than Nr. 3 must probably 
be explained by the fact that the pointing was made on one of the 
dark rifts. 
All the observations having been made through clouds the question 
naturally arises how far the result of the observations can have 
been disturbed by this circumstance. It might be that a cloud or 
40% 
