[12]In reference to such prominences on the lunar surface as cast steeple-like shadows, it is well to remark that we must not in all cases infer, from the acute spire-like form of the shadow, that the object which casts the shadow is of a similar sharp or spire-like form, which the first impression would naturally lead us to suppose. A comparatively blunt or rounded eminence will project a long and pointed shadow when the rays of light fall on the object at a low angle, and especially so when the shadow is projected on a convex surface. We illustrate this with a copy of an actual photograph of the shadow cast by half a pea, Fig. 41. [13]We meet a difficulty in reconciling this idea with the partial craters of which we have a conspicuous example in Fracastorius, No. 78, of our Map, which seem to be partially sunk below the contiguous surface. This looks as though the crater-rim belonged to an older epoch than the plain from which it rises. [14]We are informed by a friend, who has lately visited Athens, that Schmidt’s detail drawings of the Moon, comprising the work of forty years, form a small library in themselves. The map embodying them is so large (6 ft. 6 in. in diameter) and so full of detail that there is small hope of its complete publication, unless there should be such a wide extension of interest in the minute study of our satellite as to justify the cost of reproducing it. [15]It is conceivable that the alleged changes in the crater Linné may have been caused by a filling of the crater by some such crumbling action as we are here contemplating. [16]Is it not conceivable that the protogerms of life pervade the whole universe, and have been located upon every planetary body therein? Sir William Thomson’s suggestion that life came to the earth upon a seed-bearing meteor was weak, in so far that it shifted the locus of life-generation from one planetary body to another. Is it not more philosophical, more consistent with our conception of Creative omnipotence and impartiality, to suppose that the protogerms of life have been sown broadcast over all space, and that they have fallen here upon a planet under conditions favourable to their development, and have sprung into vitality when the fit circumstances have arrived, and there upon a planet that is, and that may be for ever, unfitted for their vivification? [17]Our remarks have general reference to a region of the moon near her equator; near the poles some of the conditions we shall describe would be somewhat modified.