1461 
zones contribute to the strip A. Though possible, it is extremely 
tedious to calculate these surfaces. We therefore determined them 
by cutting out and weighing the pieces of each strip. So the unit 
of area, adopted for measuring the surfaces, corresponds to a piece 
of our drawing-paper weighing 1 milligram. Expressed in that unit, 
the coëfficients 9, ,0,...@, were found to be 8,1, 11,9. ...., 298. 
Table MH contains all. the coéiicients of zis, 4, Je is ts thus 
danser E IE 
Coëfficients of: 
Increments. 7 5 | 
a= 41 251.0 
b= 53.5 | 83.0168.4 
c= 58.5 | 25.5) 88.5137.5 
| 34.5 78.5 123.0 
| 
d= 62 | 13.8 
e=130 | 15.7) 37.5 59.6113.0 264.0 
10.9 
5 
f=135 10.9; 21.0) 31.1) 45.0/163.0/2177.0 
0 
g=140 | 8.5 15.0 19.5 27.0 80.0 146.0 192.0 
h=144 | 8.1) 11.9 15.8 21.1) 55.3 77.0/298.0 
i=147 | 7.7) 10.3) 12.3) 15.9| 42.0, 55.5/198.0146.5 
j=150 | 7.4) 9.3 11.0 13.2) 33.0 42.0 123.5 247.0 | | 
k=152 | 7.1) 8.4 9.2 11.9 28.7 34.8 93.5/168.5 120.0 | 
1=153 | 6.9 8.2 8.8 10.2 25.4 30.2 76.6108.2204.2 
m=154 | 6.9 8.1 8.5 9.8) 22.4 27.5) 66.0| 86.5/142.0 08.2 
n=154.5 | 6.8| 8.0] 8.3. 9.5| 20.8 24.9] 58.0] 13.4 96.41165.3 
o=1ö4 | 6.8 7.7 8.1 9.2 19.8 22.6 52.5 63.6 77.8119.7 77.7 
p=154 | 6.8| 7.6| 8.0 9.0 19.1) 21.1} 49.1 57.3. 66.2 82.2134.0 
g=154 | 6.1 7.5| 7.8 8.8) 18.3, 19.7| 44.9] 53.0) 57.7, 68.9,164.7 
r=153.5 | 6.1 7.4 7.6 8.6 17.6 19.0) 42.4| 49.7] 53.4 69.0181.2 
s=152.5 | 6.8 7.5 7.6 8.4) 17.0 18.2| 40.3 45.5| 49.2) 54.5/143.0) 50.3 
t= 151.5 | 6.8| 7.5| 7.5| 8.2) 16.7 17.5] 39.2| 42.9] 46.5] 51.1/115.3| 83.6 
u=140.5 | 6.8| 7.4| 7.5 8.1| 16.5| 17.1) 38.0) 41.7| 45.1] 48.3 102.0] 97.0 
obtained. The first column gives the values of the increments of 
the radiation as read on the eclipse-curve. Every horizontal row 
95 
Proceedings Royal Acad. Amsterdam. Vol. XV. 
