Many instances of both kinds will be found mentioned in the chapter on historical lunar eclipses.[113] [Illustration: FIG. 14.—CONDITIONS OF ECLIPSES OF THE MOON.] The different conditions of eclipses of the Moon are illustrated by Fig. 14 which must be studied with the aid of the remarks made in a former chapter concerning the apparent movements of the Sun and Moon and their nodal passages. Suffice it to state here that in Fig. 14 AB represents the ecliptic, and CD the Moon’s path. The three black circles are imaginary sections of the Earth’s shadow as cast when the Earth is in three successive positions in the ecliptic. If when the Earth’s shadow is near A the Moon should be at E, and in Conjunction with the Earth the Moon will escape eclipse; if the Conjunction takes place with both the Earth’s shadow and the Moon a little further forward, say at F, the Moon will be partially obscured; but if the Moon is at or very near its node, as at G, it will be wholly involved in the Earth’s shadow and a total eclipse will be the result. In the case contemplated at G in the diagram, the Moon is concentrically placed with respect to the shadow, but the eclipse will equally be total even though the two bodies are not concentrically disposed, so long as the Moon is wholly within the cone of the Earth’s shadow.[114] Just as in the case of the Sun so with the Moon there are certain limits on the ecliptic within which eclipses of the Moon _may_ take place, other (narrower) limits within which they _must_ take place, and again other limits beyond which they _cannot_ take place. Reverting to what has been said on a previous page[115] with respect to these matters when an eclipse of the Sun is in question it is only necessary to substitute for the word “Conjunction,” the word “Opposition”; and for 18½° and 15¼° of longitude the figures 12½° and 9¼°. The limits in latitude will be 1° 3′ and 0° 52′ instead of 1° 34′ and 1° 23′. These substitutions made, the general ideas and facts stated with regard to the conditions of an eclipse of the Sun will apply also to the one of the Moon. It is to be noted that whereas eclipses of the Sun always begin on the W. side of the Sun, eclipses of the Moon begin on the E. side of the Moon. This difference arises from the fact that the Sun’s movement in the ecliptic is only apparent (it being the Earth which really moves), whilst the Moon’s movement is real.