LETTER VI - The Nebulæ

Summary

The disclosures of the telescope are now before us5—the entire perspective of Modern Astromomy. Can we comprehend its wonders? Are its arrangements a fixed thing—a mere passing show—or are they results of a pre-existing state, and germinant of something future? These questions warn me, that again we break new ground, and enter on speculations, perhaps the most adventurous which have yet engaged the reason of Man.

Astronomy has recently been obliged to recognise a Matter—or rather a modification of Matter, wholly distinct from stars—a thin and filmy substance diffused through the stellar intervals, and spreading over regions so immense, that its magnitude or the space it fills, is absolutely inconceivable. It unquestionably becomes us not to admit an element so remarkable, and which, if real, must perform important functions, and materially affect our general views of things—until its claims have undergone the severest scrutiny ; and as I am desirous to convey to you full power of judging for yourself, I will here minutely follow the process of thought, by which Sir, William Herschel—only, however, at a comparatively late period in the course of his researches—was, slowly and almost reluctantly, led to the conviction of its reality.

In his earlier inquiries, Herschel was inclined to consider all the faintly illuminated spots in the heavens, as clusters so remote, that only their general illumination, and no individual object could be seen; and the inference, so far from being constrained, seemed to result from his whole previous experience.