12 REPORT—1862, 
German map, “Pythagoras ;” while to prevent misapprehension as to the western 
walled plain with the included crater, and to distinguish it from the eastern crater, 
it is proposed to call it “ Babbage.” 
Ix. Pythagoras (Riccioli), The largest and most magnificent crater in this part 
of the moon, showing itself as a conspicuous object with its central mountain, when 
nearly the whole of the previously-described craters and walled plains are lost 
to view. 
X. Horrebow (Schroter). This crater, which pierces the S.W. angle of the rim of 
Herschel, has hitherto been treated as being independent of any other formation. 
Schroter, who named it, figured it in its proper position at the west of the mountains 
F, and he gives (see T. xxvi. fig. 1, above referred to) the chain of mountains, 
omitted by Beer and Madler, forming the continuation of the rim from the steep 
mountains F to the rim of Anaximander, where he gives a small crater shown in 
the eye-sketch. On the other hand, Schroter has omitted the western rim extending 
northwards from Horrebow, which is given by Beer and Midler. Horrebow is 
clearly a part of Herschel II. 
Schroter does not appear to have recognized or figured “ South.” 
On the Augmentation of the Apparent Diameter of a Body by its Atmospheric 
Refraction. By the Rev. Professor Cuatuis, M.A., F.RS., F.RAS. 
For reasons given in another communication, it was assumed that atmospheres 
generally have definite boundaries at which their densities have small but finite 
values. Two cases of refraction were considered: in the one, the curvature of the 
course of a ray through the atmosphere was assumed to be always less than that 
of the globe it surrounds; and in the other, the curvature of the globe might be 
the greater. The former is known to be the case with the earth’s atmosphere ; and 
it was supposed that, a fortiori, this must be the case with respect to any atmo- 
pape the moon may be supposed to have. On this supposition it was shown that 
the apparent diameter of the moon, as ascertained by measurement, would be greater 
than that inferred from the observation of an occultation of a star, because, by reason 
of the refraction of its atmosphere, the star would disappear and reappear when 
the line of vision was within the moon’s apparent boundary. The same result 
would be obtained from a solar eclipse. It was stated that, by actual comparisons 
of the two kinds of determinations, such an excess to the amount of from 6” to 8” 
was found. This difference may reasonably be attributed to the existence of a lunar 
atmosphere of very small magnitude and density. The author also stated that 
from this result there would be reason to expect, in a solar eclipse, that a slender 
band of the sun’s disk immediately contiguous to the moon’s border would be some- 
what brighter than the other parts, and advised that especial attention should be 
directed to this point on the next occurrence of a solar eclipse. The case in which 
the curvature of the path of the ray is greater than that of the globe was assumed 
to be that of the sun’s atmosphere; and it was shown, on this supposition, that all 
objects seen by rays which come from the sun’s periphery are brought by the re- 
fraction to the level of the boundary of the atmos fs 
from objects on the surface of the interior globe, or from clouds supposed to be sus- 
pended in the atmosphere. Accordingly, the contour of the sun should appear 
quite continuous, and the augmentation of ba ik semidiameter will be equal to 
the angle subtended at the earth by the whole height of the atmosphere. The 
apparent diameters of the planets will, for like reasons, be augmented to a certain 
amount by their atmospheric refractions; and on account of the great distances of 
these bodies from the earth, the eclipse of a satellite will take place as soon as the 
visual ray is bent by the interposition of the atmosphere. 
On the Zodiacal Light, and on Shooting-Stars. 
By the Rev. Professor Cuatuis, M.A., F.RS., F.RAS. 
_ The phenomena of the zodiacal light, as gathered from observations made both 
in northern and in southern latitudes, were stated to be as follows. As seen in north 
latitudes, it appears in the West after the departure of twilight, as a very faint light, 
ere, whether they proceeded ~ 
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