AREOGRAPHY.
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taneously the Lick observers noted what they called streaks in the same regions. These markings were as their names imply irregular or indeterminate. Nor were they credited by their discoverers with
significance beyond what the names import. They were thus of the same transition character as Dawes' delineations. But Pickering drew some important inferences from what he saw. From what he detected
he concluded that the greater part of these dark areas could not be seas as they had been supposed to be even by Schiaparelli. Schaeberle and Barnard on this and on other grounds advanced something of the same theory.