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rupting the tendency sometimes observed in telescopic star-disc to become 
triangular. An interesting discussion arose at a late meeting at the Astro- 
nomical Society, on this singular tendency. It has been observed by Mr. 
Dawes to occur only when the wind is from the east. The Astronomer Royal 
ascribed it to the effects of an easterly wind on the health, an opinion, how- 
ever, in which many experienced observers do not coincide with Mr. Airy. 
The fact that a particular aperture corrects the tendency seems, also, 
decisive on this point. A kindred phenomenon, the circumstance that a 
shorter focus is required for objects near the horizon or seen through a haze, 
was discussed in connection with the other. Here again the Astronomer 
Royal held an opinion not accepted by several distinguished observers. He 
ascribed the phenomenon to the difference between direct and skew vision. 
We believe that Mr. Dawes never uses skew vision, his observing chair 
being ingeniously contrived so as to give in all cases direct (and com- 
fortable) vision. The fact that a short focal length is required for parts of 
the sun near the limb, and a long focal length for the moon, seems to show 
that the question is merely one of distinctness of objects. In proof of 
which we may quote Mr. Dawes’ observation, that young observers, in their 
anxiety to see perfectly well while setting the focus, use nearly always too 
short a focal length. Here our comment on Mr. Dawes’ valuable paper 
must cease ; but we commend the whole of it to the most careful study 
of the telescopic observer. 
An error in M. Leverrier’s calculation of the sun’s distance from the 
earth’s parallactic inequality has been detected by Mr. Stone. The result 
is to reduce the estimate by 400,000 miles, or to give the value already 
obtained by M. Hansen. Mr. Stone has himself obtained a new estimate. 
His calculation, founded on the observation of Mars/ gave, as our readers are 
aware, 8" ^4, for the sun’s equatorial horizontal parallax — the same value, 
nearly, as had resulted from Leverrier’s faulty calculation. Mr. Stone’s 
examination of Greenwich lunar observations, bearing on the lunar pa- 
rallactic inequality, gives a parallax of 8"‘85. The values now being obtained 
by different astronomers cluster closely round M. Hansen’s value 8 /A 916. 
Mr. Stone has examined the question of the sun’s motion in space, with 
results confirmatory of those already obtained. But he considers that the 
sun’s motion is not so great as that of most stars. 
He has also examined the interesting question of possible changes in the 
earth’s axis of rotation, accruing from the action of the tides. He finds no 
evidence pointing to the possibility of appreciable change, even in long 
intervals of time. 
The eclipse which occurred on the morning of March 6, was observed by 
several astronomers. One observer noticed that the penumbra of a spot on 
the sun appeared to grow indistinct as the moon’s limb approached it, an 
observation suggesting the existence of a lunar atmosphere of small extent. 
Mr. Browning and Mr. Lassell noticed that a snow storm occurred in the 
upper regions of air during the progress of the eclipse. We find nothing 
else worthy of special record. 
From India we hear that the November meteors were well seen at 
Kishnagur, fifty miles north of Calcutta. Places from which the shower 
is now known to have been seen range over a full fourth of the earth’s 
surface. 
