Madam,

I have been induced to make the brief series of letters addressed to you, thus public, because of a regret which, I believe, is widely felt, that the discoveries made in recent years, throwing most unexpected light upon the constitution—present and remote—of the Stellar Universe, should longer continue comparatively unknown, and concealed amid the varied and massive collections of our 'Learned Societies. Unfortunately, I am not at present in a condition to bestow on these discoveries a shadow of original interest, so that, in description, my pen can have only a borrowed liveliness; but as the illustrious men who share the glory of having achieved such acquisitions for mankind, have, not unequivocally, shown a disinclination to the humbler task of reducing them into a popular system, we have only the choice of consenting, that matter of unusual importance shall remain unfitted to fulfil the best purpose of truth—which is to instruct and elevate the general mind—or to permit the work to be attempted by some one with pretensions no higher than my own.

Previous to the commencement of this century the facts and speculations about to engage us were unknown in science. Before then, the planetary orbits seemed to encircle all accessible space ; they had eiFectively constituted bounds to systematic enquiry, for astronomers had never adventured into greater remotenesses, having, like the people, gazed at the farther heavens with vague and incurious eye—content to admire their beauty and confess their mystery.