That these stones are projected from lunar volcanos, very strong reasons have been assigned to prove. As 1. Volcanos in the moon have been observed by means of the telescope. 2. The lunar volcanos are very high, and the surface of that globe suffers frequent changes, as appears by the late observations of Schroëter. 3. If a body be projected from the moon to a distance greater than that of the point of equilibrium, between the attraction of the earth and the moon, it will, on the known principles of gravitation, fall to the earth. 4. That a body may be projected from the lunar volcanos beyond the moon’s influence, is not only possible, but very probable; for on calculation it is found, that four times the force usually given to a twelve pounder, will be quite sufficient for this purpose: it is to be observed, that the point of equilibrium is much nearer; and that a projectile from the moon will not be so much retarded as one from the earth, both on account of the moon’s rarer atmosphere, and its less attractive force.[123] Of all the phenomena of the heavens, there are none which engage the attention of mankind more than _eclipses_ of the sun and moon; and to those who are unacquainted with the principles, nothing can appear more extraordinary than the accuracy, even to a second of time, with which they are predicted. Eclipses of the sun are occasioned by the shadow of the intervening new moon falling on the earth, and those of the moon are caused by the shadow of the earth falling on the full moon, the earth at the full moon being always in a direction between the sun and moon.