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 would be rendered manifest by the disturbance of the little moons from the paths which they had so long traversed. Careful attention was directed to this point in order to see whether, after the collision between Jupiter and Lexell's comet, the satellites offered any indications of the vicissitudes through which they had gone. The evidence on this point was entirely negative. It was not possible to discover any irregularity in the movements of the bodies which could be attributed to the attraction of the comet. It has thus been demonstrated that, notwithstanding the stupendous bulk of a great comet, its mass must have been so inconsiderable as to have been insufficient to disturb even such unimportant members of the solar system as the satellites of Jupiter.

These different lines of reasoning convince us that comets contain no appreciable portion of actual solid material. But meteorites are shown from their structure to be fragments rent from some mighty mass which has cooled but slowly from a highly heated state. They resemble certain volcanic products so closely that it seems quite impossible to refuse assent to the doctrine of Tschermak that, whatever be their source, the materials must have come from gigantic masses, not greatly varying in dimensions from the earth or other solid planets of our system. But we have seen that comets are in every respect different from bodies possessing the characteristics of objects from which meteorites can have been derived. I am, therefore, forced to the conclusion that meteorites and comets can have no connection, except what may be implied in the circumstance that they all belong to the solar system.

I am quite aware that this view is very different