Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. This book is the result of a special study of the planet made during the last opposition, at an observatory put up for the purpose of getting as good air as practicable, at Flagstaff, Arizona. A steady atmosphere is essential to the study of planetary detail: size of instrument being a very secondary matter. A large instrument in poor air will not begin to show what a smaller one in good air will. When this is recognized; as it eventually will be, it will become the fashion to put up observatories where they may see rather than he seen.<br><br>Next to atmosphere comes systematic study.
Lebih banyak ebook daripada pengarang yang sama / Penyunting
5,025 Ebooks dalam kategori ini
