Wow, that engraving looks like a photo!
Curious what the book says about galaxies. Were they considered island universes or planetary systems in the making within our own galaxy?
Here is a post I made in January 2021 that is related to this question:
I wrote an article titled "Island Universes from Wright to Hubble" that was published in S&T January 1999. There is rich, interesting history left out of textbook treatment of the existence of external galaxies. In fact, when Hubble observed Cepheid variables in M31 and convinced the world of external galaxies, it was the second time that the world of Astronomers concluded that "nebula" are external galaxies.
Prior to 1870, astronomers thought that most nebula were external galaxies. Then, around 1869, Richard Anthony Proctor made arguments that caused astronomers to abandon the view that nebula are external galaxies. Proctor's arguments caused a change of view because they were based upon observations.
I discovered this when I was collecting antiquarian Astronomy and other science books.
Here are a few quotes I included in the article:
From Proctor's book "Other Worlds Than Ours" (1870): "Yet once more, according to accepted views, thousands and thousands of galaxies, external to the sidereal system, can be seen with powerful telescopes."
From Thomas Dick's book "Sidereal Heavens" (1840): "Winging our flight from the Milky Way over unknown and immeasurable regions, regions where infinitude appears opening upon us in awful grandeur, we approach some of those immense starry clusters called the Nebulae, every one of which may be considered another Milky Way, with its ten thousands and millions of suns."
And then after 1870 in Simon Newcomb's large Astronomy Treatise titled "Popular Astronomy" (1884): "This idea that the nebulae were other galaxies was more or less in vogue among popular writers until a quite recent period."
Anyway, Most people don't know that until ~1870 the idea that nebulae were external galaxies was a commonly accepted view. Arguments based upon the distribution of nebula and other observations led astronomers to change their mind. And then it came around again in the decade before Hubble finally proved it with Cepheid variables in M31.
From this thread:
https://www.cloudyni...d-the-universe/
As to this book by Young, I have an 1898 printing of the book. On page 560561 Young says the following:
Distance of the Nebulae - On this point we have very little absolute knowledge. Attempts have been made to measure the parallax of one or two, but so far unsuccessfully. Still it is probable, indeed almost certain, that they are at the same order of distance as the stars. [/quote]
He goes on to say on page 561:
Fifty years ago a very different view prevailed. as has been said already, astronomers at that time very generally believed that there was no distinction between nebulae and star-clusters except in regard to distance, the nebulae being only clusters too remote to show the separate stars. The considered a nebula, therefore, as a "universe of stars," like our own "galactic cluster" to which the sun belongs, but as far beyond the "star-clusters" as these were believed to be beyond the isolated stars. In some respects this old belief strikes one as grander than the truth even. It made our vision penetrate more deeply into space than we no dare think it can.
Of course the typical textbook history of Hubble's discovery and the "great debate" misses this reality that up until about 1870, most astronomers actually thought the nebula were external Milky Ways. But arguments in the 1870's shifted the thinking to the idea that all nebulae are actually part of the Milky Way. I discuss all this in my 1999 S&T article, but the immediate quote above is one I either missed or did not make the editing into the published version of the article.
Dave
Edited by russell23, 23 May 2025 - 08:36 PM.