356 REPORTS ON THE STATE OF SCIENCE, ETC. 
TABLE II. 
CALCULATION oF P Atona Lines A, B, C, D oF PRINCIPAL STRESS. 
p y P-Q P Q 
(obs.) (obs. ) (obs. ) (Q—P)ecoty (Graphical) | (Graphical) 
( u7e — 0 0 0 0 
15° 161-5° 0-40 1-20 0-02 —0-38 
A 10° 157-5° 1-50 3-62 0-18 —1-32 
5° 151-5° 2°72 5-00 0:56 —2-16 
0° 90° 4-20 0 0-93 —3:27 
32° 30’ — 0 0 0 0 
30° 144-5° 0-28 0-39 0-01 —0:27 
25° 144° 0-89 1-23 0-06 —0-82 
B 20° 143° 1-60 2°13 0-21 —1:39 
5 137-5° 2-50 2-72 0-42 —2-08 
10° (BH 3-27 2-84 0-67 —2-60 
aye 124° 3-91 2-62 0-92 —2-99 
0° 90° 4°35 0 1-06 —3-29 
48° — iat 0 0 0 
45° 134° 0-43 0-42 0-01 —0-42 
40° 131° 0-83 0-72 0-06 —0:77 
Bop 129° 1-44 1-17 0-14 —1-30 
30° 129-5° 2-00 1-64 0:27 —1-74 
Cc 25-e. 124° 2-90 1-94 0-42 —2-48 
20° 121° 3°60 2-16 0-60 —3-00 
15° 122° 4-15 2:57 0-80 —3-35 
10° 115-5° 4-55 2-18 1-02 —3:53 
be 108° 4-82 1-54 1-18 —3-64 
0° 90° 4-85 0 1-25 —3-60 
63° — 0 0 0 0 
60° 128° 0-75 0-58 0-01 —0:74 
55° 118° 1-90 1-01 0-08 —1-82 
50° 114° 2-85 1-27 0-17 2:68 
45° iss 3-40 1-44 0-29 —3-11 
40° 113° 3-90 1-65 0-42 —3-48 
D noe 113° 4-25 1:80 0-57 —3-68 
30° 115° 4-70 2°19 0-74 —3-96 
25° 114°] 5-15 2-29 0-93 —A4-22 
20° 108° 5-55 1-80 1-12 —4-43 
15° 105° 5-90 1-58 1-27 —4-63 
10° 101-5° 6-15 1-25 1:39 —4-76 
ayy 97° 6-30 0-77 1-48 —4-82 
0° 90° 6-40 0 1-50 —4-90 
In computing the above table the values of (Q — P) cot ¥ were plotted to ¢ on 
squared paper and the areas read off by counting squares. 
It will be noticed that we have now a system of values of P and Q which practically 
cover the whole of the disc, excluding the immediate neighbourhood of the points 
of application of the load. Our problem is therefore practically solved. . | 
8. Comparison with the theory along the diameter x = 0 shows divergences, 
e.g. the progressive rise, as we move away from O, in the value of P, which in the 
i al 
