& SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 
eveometrical regularity of the lnes pointed to an intelligent 
origin, and the probability that Mars is inhabited was a fre- 
quent theme of.discussion, both by astronomers and laymen. 
The astronomer who has been foremost in supporting this 
view during the present decade is Percival Lowell, whose ex- 
ceptional facilities for observation at Flagstaff, give his opin- 
ion great weight. The high altitude of his observatory—7,000 
feet; its low southern latitude, bringing the planet many de- 
grees nearer the zenith than Yerkes, Harvard, Greenwich and 
other large observatories; the powerful refractor (24-inch ob- 
jective) with which he is equipped; the freedom from atmos- 
pherie disturbances on his elevated plateau, giving him un- 
usually ‘‘good seeing;’’ and above all, the keen eyesight of 
Professor Lowell—almost a special gift; all these combined 
advantages have enabled him to study the planet under ideal 
conditions, and thus to reach just conclusions. 
He believes that the geometrical figures he has observed on 
the surface of the planet were designed by engineers of no 
mean order of intelhgence. They are not myths, but actually 
exist and are clearly defined and readily mapped. at certain 
Martian seasons, become dim and in some places fading out at a 
later stage, only to distinctly reappear at the return of the 
former season. They are not geological cracks in the crust of 
Mars, for the chances are more than a million to one against 
chance cracks arranging themselves into a system so orderly 
and symmetrieal. 
In order to secure a still better station for the observation 
of Mars while in astronomical proximity to the earth, Prof. 
David Todd established himself at a high altitude in the Andes, 
where the planet was nearly overhead, and succeeded in taking 
some 7000 photographs, many of which are so clear and excel- 
lent that they not only show the canals with remarkable dis- 
tinctness, but even the doubling of many of the canal-like lines. 
The latter is a phenomenon hitherto observed only with the 
eye, and these photographs forever set at rest all cavil regard- 
ing the existence of these enigmatical lines. Thus does the 
beautiful art of photography supplement and confirm the 
patient, keen-eyed observations of the skillful astronomer. 
N ature of the Canals. 
Conceding, then, the existence and the artificial origin of 
these canals, the question arises, what is their nature; how are 
they produced; what purpose do they subserve? But first, let 
us consider one of the most serious objections which have - 
been raised by astronomical writers against the habitability of 
Mars, namely, its assumed low temperature. The earth is 
