Autor: Agnes Mary Clerke, Alfred Fowler, John Ellard Gore. Agnes Clerke (1842–1907) was a successful author of books on astronomy and its history (three of her other works being reissued in this series), and her co-authors were astrophysicist Alfred Fowler, an internationally renowned expert in spectroscopy, and J. Elland Gore, a Fellow of the Royal Astronomical Society and expert on variable stars.
