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or indeed ever will be, disproved. I do not know that there is much novelty 
in my views,” &c. And then he proceeds to go over the old ground, very 
nearly along the old course, coming naturally to very nearly the same goal 
that W. Struve, Von Littrow, and others have reached. Mr. Stone’s mathe- 
matical treatment of the portion of the evidence which he selects is of 
course perfectly sound; and if only that portion is considered, then un- 
questionably the conclusion at which he arrives must be regarded, not 
indeed as demonstrated, but as the conclusion which has in its favour the 
greatest weight of probability. But as there is a great deal of much 
weightier evidence, which he entirely omits to consider, and as that 
evidence is not merely opposed to the general conclusion at which Mr. 
Stone arrives, but demonstrates the incorrectness of that conclusion, the 
care and skill with which the imperfect evidence is dealt with, are in reality 
thrown away. Mr. Stone deals with the observed increase of numbers in 
stars down to Argelander’s ninth magnitude, comparing that increase with 
what would occur if stellar brightness depended in general on distance, stars 
being scattered with general uniformity throughout space ; and he finds a 
general accordance between this theory and the observed facts, whence he 
deduces the conclusion that the theory is sound. But as it is certain that if 
the theory were sound there would be no real aggregations or rather segre- 
gations (in space) of stars of many orders of real magnitude, and as if there 
were no such aggregations there would certainly be no apparent aggregations 
of stars of many orders of apparent magnitude on the star-vault, it follows 
certainly that if such apparent aggregations exist, the theory of general 
uniformity of distribution is incorrect. It would not follow certainly, if no 
such aggregations existed, that the theory was sound, but it is certain that 
if they exist the theory is unsound. But it has been shown that they exist. 
They are made manifest to the eye in Mr. Proctor’s equal-surface chart of 
324,000 stars, where in some parts the stars are so closely set that there is 
barely room for them, minute though their discs are, while elsewhere they 
are strewn very sparsely — the regions rich in stars of the leading orders of 
apparent magnitude being those_ very portions of the Milky Way in which 
stars down to the twentieth magnitude are found in greatest numbers. The 
theory, then, of a general equality in the distribution of stars in space, even 
in the neighbouring parts of the system of stars, cannot be sound. As Mr. 
Proctor pointed out in a paper read at the May meeting of the Astronomical 
Society, if a surveyor were to urge against a theory respecting certain mounds 
that the mounds have in reality no existence, seeing that, if they were 
levelled, the general level of the ground would be very nearly the same as 
though the mounds had not been there — his arguments would not be 
thought to have much weight. Mr. Stone’s theory (sound though its mathe- 
matical portion is) is of a similar kind. It is simply a demonstration of the 
fact that if we leave out of consideration the aggregations of stars on the 
star vault, these aggregations no longer afford any evidence of the real aggre- 
gation of stars in space. 
Approaching Opposition of Mars. — Dr. Terby, of Louvain, who has devoted 
much attention to the subject of the charting of Mars, calls attention to the 
questions which he has raised in his memoir on the subject. These questions 
are quoted elsewhere in the present number. He begs astronomers to com- 
