Mr. Ivory on the Theory of the Asti'onomicalllefr actions, 97 
Zenith 
dist. 
Reflections. 
New Table. 
Tab. Reg. 
Conn, des Temps. 
o 
II 
II 
n 
10 
10-30 
10-30 
10-30 
20 
21-26 
21-26 
21-26 
30 
33-72 
33-72 
33-72 
40 
48-99 
48-99 
48-99 
45 
58-36 
58-36 
58-36 
50 
69-52 
69-52 
69-52 
55 
83-25 
83-24 
83-25 
60 
100-85 
100-85 
100-86 
65 
124-65 
124-62 
124-65 
70 
159-16 
159-11 
159-22 
75 
214-70 
214-58 
214-83 
80 
320-19 
319-88 
320-63 
81 
353-79 
353-38 
354-33 
82 
394-68 
394-20 
395-37 
83 
445-42 
444-86 
445-87 
84 
509-86 
509-23 
511-22 
85 
593-96 
593-38 
595-80 
851 
646-21 
647-10 
618-34 
86 
707-43 
707-15 
710-07 
861 
779-92 
777-36 
783-07 
87 
866-76 
864-59 
870-37 
87i 
971-93 
972-21 
975-89 
88 
1101-35 
1101-40 
1105-1 
881 
1262-6 
1265-5 
1265-0 
89 
1466-8 
1481-8 
1464-9 
891 
1729-5 j 
1764-9 
1716-4 
From this view it appears that the three tables agree within 
less than 1" as far as 80° from the zenith ; the new table 
is in accordance with Bessel’s, with slight discrepancies, to 
88° or 88^° from the zenith ; from 80° to 88° of zenith di^ 
stance the numbers in the French table exceed those in 
Bessel’s, the excess being 2" at 84?°, and 4<" at 88°. But 
when the distance from the zenith is greater than 80°, the 
accuracy of the French table is questionable, both on account 
of the hypothetical law of the densities, and because the quan- 
tity assumed for the horizontal refraction is uncertain. 
A few examples are subjoined, as well for explaining the 
use of the new table as for affording some indications of its 
accuracy at low altitudes. The two first instances are taken 
from the Tables Astronomiques, and are likewise published 
yearly in the Conn, des Temps. 
Phil, Mag, S. 3. Vol. 16. No, 101. Feb, 184?0. H 
