MR. R. T. GLAZEBROOK ON PLANE WAVES IN A BIAXAL CRYSTAL. 
315 
the third those of /x (corrected by interpolation for the wave E) ; and the fourth the 
values of /x from Table III. ; while the last column gives the differences between the 
two sets. 
Comparison of values of /x deduced from two independent series of observations at an 
interval of about two months. 
Table XXVII.—Wave 0. 
0'. 
1 
16 27 16 
1-68131 
2 
17 32 15 
1-68127 
3 
18 36 18 
1-68128 
4 
19 39 22 
1-68126 
5 
20 41 22 
1-68129 
6 
21 42 8 
1-68120 
7 
22 41 41 
1-68128 
8 
23 39 55 
1-68125 
9 
24 36 48 
1-68116 
10 
25 32 5 
1-68127 
11 
26 25 51 
1-68116 
12 
27 17 37 
1-68130 
13 
28 8 10 
1-68116 
14 
29 32 20 
1-68127 
15 
28 56 42 
1-68106 
Table XXVII. continued.—Wave E. 
0'. 
/o 
Values of p. 
reduced to the values 
of <p' in Table II, by 
interpolation. 
Values of p from 
Table III. corresponding 
to the same values of <p' 
as in previous column. 
Excess of the first series 
over the second. 
29 19 59 
1-68108 
1-68115 
29 43 27 
1-68066 
1-68075 
1-68073 
•00002 
30 6 16 
1-68029 
1-68038 
1-68032 
•00006 
30 28 56 
1-67991 
1-68000 
1-67996 
•00004 
31 12 9 
1-67905 
1-67914 
1-67918 
—-00004 
31 53 13 
1-67828 
1-67837 
1-67841 
--00004 
32 32 10 
1-67743 
1-67752 
1-67756 
—-00004 
33 8 28 
1-67668 
1-67678 
1-67674 
■00004 
33 42 29 
1-67590 
1-67600 
1-67591 
•00009 
34 13 53 
1-67508 
1-67518 
1-67519 
- -00001 
34 42 22 
1-67450 
1-67461 
1-67450 
•00011 
35 8 27 
1-67368 
1-67380 
1-67388 
--00008 
Taking the observations for the wave O first, we observe that they do not differ 
greatly from those given for the same values of in Table II., except in the case of 
those which correspond to lines 12, 13, 14, of Table III., at which points the new values 
2 s 2 
