When we come to photographs, the process is carried to a third stage. The image is formed by the telescope, subject to all the limitations of telescopic images, and is received on a plate essentially granular in structure, and is finally examined by the eye. The granular structure of the plate acts as the third factor in concealing irregularities and simplifying details; a third factor in producing the two simplest types of form--the straight line and the circular dot. Prof. Lowell describes the canals as like lines drawn with pen, ink and ruler, but not a few of our best observers have advanced much beyond this stage. Even as far back as 1884, some of the canals were losing their strict rectilinear appearance to Schiaparelli, and the observers of the planet who have been best favoured by the power of the telescope at their disposal, by the atmospheric conditions under which they worked, and by their own skill and experience--such as Antoniadi, Barnard, Cerulli, Denning, Millochau, Molesworth, Phillips, Stanley Williams and others--have found them to show evident signs of resolution. Thus, in 1909, Antoniadi found that of 50 canals, 14 were resolved into disconnected knots of diffused shadings, 4 were seen as irregular lines, 10 as more or less dark bands; and he found that, in good seeing, there was no trace whatever of the geometrical network. The progress of observation, therefore, has left Prof. Lowell behind, and has dispelled the fable which he has defended with so much ingenuity. But, indeed, there never was any more reason for taking seriously his theory as to the presence of artificial waterways on Mars than for believing in the actual existence of the weird creatures described by H. G. Wells in the _War of the Worlds_. There are too many oversights in the canal theory. Thus no source is indicated for the moisture supposed to be locked up in the winter pole cap. Prof. Lowell holds that there are no large bodies of water on the planet; that the so-called seas are really cultivated land. In this case there could be little or no evaporation, and so no means by which the polar deposits could be recruited.