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 happen that the wondrous multiple did actually lie inside the nebula wherein it was seen gleaming. But it is, no doubt, conceivable that the effect actually witnessed might be accounted for if it should happen that the multiple star were billions of miles in the foreground, only so placed that from our point of view we beheld it projected with the brightest part of the nebula as a background. Such, too, is the translucency of nebulous material that it is at least a conceivable hypothesis that the nebula might be the object which lay in the foreground and that the star occupied a position billions of miles in the rear, but that from where we were situated our line of sight towards the star conducted our vision directly through the centre of the nebula.

We have really no means of certainly knowing which of these notions is the correct one. At least, I should say, direct observation cannot be held to have shown conclusively that one of these doctrines is true and that the other two are false. It could only have done so when we had measured the distances of both the nebula and the multiple star from the earth. As a matter of fact we have not measured the distance of either the one or the other. This is eminently a case in which the theory of probabilities can be suitably applied, and the result to which it leads is of no uncertain kind. It demonstrates, by a line of reasoning the cogency of which cannot be impugned, that the famous stars are not