Annals of the Lowell Observatory Volume 1

Annals of the Lowell Observatory Volume 1

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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1898 edition. Excerpt: ...be the course to take to conduct water, with the least expenditure of time or trouble, from the one to the other. The circular shape of the oases is as directly economic as is the straightness of the canals; for the circle is the figure which incloses the maximum area for the minimum average distance of points within it from its centre. In consequence, if a certain amount of country were to be irrigated, intelligence would suggest the circular form in preference to all others, in order thus to cover the greatest space with the least labor. n. Spots At The Edge Op The Dark Regions. We have seen what shows at one end of the canals, their inner end, namely, the oasis. But it turns out that there is also something exceptional at the other. In the Arequipa observations in 1892 and at Flagstaff in 1894 spots were seen at the edges of the so-called continents, the boundaries where the light regions and the dark regions met. These spots made their appearance very early in the Martian season, and in places where the canals left the dark areas. Upon studying them I became aware that they were, apparently, only to be met with at the mouths of the canals, and I was furthermore struck by the fact that their shape was peculiar. Instead of being round like the spots in the light regions, they were all triangular, of the form of a half-filled angle; the sort of mark with which one checks items on a list. The form is singularly appropriate, according to mundane ideas, for the spot appears before the canal itself is visible, as if to mark the place where the canal will eventually be. It lies in the so-called seas, and looks to be of the same color as they, but deeper in tint. Its shape may roughly be represented thus: V. The two sides including the obtuse angle...show more

Product details

  • Paperback | 90 pages
  • 189 x 246 x 5mm | 177g
  • Rarebooksclub.com
  • Miami Fl, United States
  • English
  • black & white illustrations
  • 1236646924
  • 9781236646927