514 PEOFESSOR HENRY A. MIERS: AN ENQUIRY INTO 
Readings for the images of the collimator signal reflected from the four cube faces 
A, B, C, D 
■A„ 163° 39i', 
A^ 163° 28', 
B 73° 33', 
C, 343° 38', 
343° 28', 
_D 253° 33'. 
As explained on p. 484, the faces A, C yield each two images lying in a horizontal 
plane, and the faces B, D two images lying in a vertical plane. 
The readings for total reflection were :— 
233° 54' light reflected at B emerging through A. 
143° 481' . ,, C „ „ B, 
53° 561' . D „ „ C. 
The angle between telescope and collimator was 88° 42'. 
On the following morning almost precisely the same readings were obtained. 
There is clearly here a difticnlty in deciding what to take as the value of the 
angle a. 
Conflning our attention to the case in which total reflection takes place at the face 
B, and taking in succession the maximum value A^B = 90° 6|-', the minimum value 
A^B = 89° 55', and the mean value AB = 90° O', the three results are ;— 
a = 90° 61', ^=-25° 53', p = 1-38951 at 16°. 
a = 89° 55', d=-26° 4l', /r = 1-38630 „ 16°. 
a =90° O', . 6'=-26" O', /r= 1-38767 „ 16° 
Finally, then, we have for the refractive index of tlie liquid in contact with a 
growing crystal of sodium chlorate at 16°, p = 1-38794 about. 
Interpreting these results the curve of Diagram III. we arrive at the conclusion 
that at 16° C :— 
(1) A saturated solution of sodium chlorate contains about 47-36 grammes of the 
substance in 100 grammes of solution; 
(2) The liquid in contact with a growing crystal contains about 47-73 grammes of 
the substance in 100 oTammes of solution. 
o 
