The Museum Gazette 



of sunset, and the appearances are sometimes spoken of 'as 

 " the new moon with the old moon in its arms." 



The moon, like the earth, rotates on its own axis, and also 

 makes a journey round the earth. It accomplishes its rota- 

 tion (which is very slow) and its revolution (or earth journey) 

 in equal periods of time. 



The fact just stated explains why the moon always pre- 

 sents the same side to our view. It follows from the same 

 fact that the moon's days are a lunar month in length, since 

 they are measured, like those of the earth, by its rotation on 

 its axis. 



The apparent rising and setting of the moon are, like those 

 of the sun, due to the rotation of the earth. 



When the earth comes between the sun and the moon an 

 eclipse of the moon occurs, and when the moon comes 

 between the earth and the sun the sun is eclipsed to us and 

 the earth is eclipsed to the moon. 



The sun measures for us our years and the moon our 

 months. In more correct terms, it is the yearly and monthly 

 recurring changes in the relation of the earth to these 

 luminaries which give us these data. 



The moon is seen with horns when young, and again when 

 old. When it is young the horns are directed to the east. 

 When they open to the west it is a waning moon. Landscape 

 artists sometimes make mistakes in this matter when dealing 

 with evening and early morning effects. In the latter the 

 horns should be to the west, and in the former to the east. 

 This is easily explained. 



During what is known as " the Harvest Moon," the moon, 

 full or nearly so, rises for several nights in succession before 

 or soon after sunset. Thus moonlight follows daylight with- 

 out the usual interval of darkness, and the labours of the 

 field may be continued into the night. The phenomenon is 

 explained by reference to the relation of the moon's orbit 

 to the eastern horizon during the autumnal equinox. These 

 conditions are repeated, though with less force, during the 



