First photographs of the canals of Mars

Abstract

To make the canals of Mars write their own record on a photographic plate, so that astronomers might have at first hand objective proof of their reality, has long been one of the objects of this observatory. The endeavour has at last succeeded. Unnecessary as such corroboration was to the observers themselves, it is different with the world at large; for the work of the camera at once puts the canals in a position where scientists in general, as well as astronomers in particular, are able to judge the phenomena. The difficulties in the way, however, at first proved insuperable. The main markings of the planet were secured by the camera here four years ago, but to get the canals to show was a matter of an altogether different order of difficulty from that of celestial photography in general. This will be appreciated on recalling Richey’s excellent photographs of the moon, within the wall of one of whose smaller craters the whole disc of the planet might be enclosed. When it is further considered that the delicate detail on this disc bears to it the same relative ratio that the craters themselves do to the whole moon, the almost impossible task of reproducing the canals will be understood.