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to spin cocoons. They like some dry twigs to crawl upon and attach 

 their cocoons to. From the cocoons later come out the moths. As 

 these cannot fly, there is no danger of their leaving. After fertilization, 

 the females will lay an immense number of eggs. These she will dis- 

 tribute over the piece of paper or cloth on which she may be placed. 

 These eggs, of course may be used to start a new colony. If it is de- 

 sired to keep the eggs for a considerable time without hatching, say, over 

 winter until mulberry leaves come again, they should be kept in a cool 

 place, neither too dry nor too moist. An ordinary cellar is a good 

 place. The length of the time of each period in the cycle of the life of 

 the moth depends on circumstances of temperature and supply of food. 

 In all stages the silk worm has its enemies, such as mice, rats, birds and 

 predaceous insects. Of course they must be protected from these if a 

 successful colony is to be maintained. 



There is so much available information in regard to silk worms and 

 silk culture, that the teacher can easily' arrange to extend the informa- 

 tion gained by the observation of the colony in the school-room. 



The noon. 



A studj^ of the motions of the moon makes a good beginning toward 

 a clear understanding of the apparent and real motions of the sun, moon 

 and stars. 



On the first evening that the moon can be seen after "new moon" 

 have the pupils note how near it is to some star. Venus may be in a 

 good position near the moon. On the following evening they are to 

 note again ics relation to this star. They may make their notes by 

 making a sketch of moon and star each night. The changing shape of 

 the illuminated part of the moon is also to be noted each night. Soon 

 the moon will be so far from the star that it cannot well be used to mark 

 the progress. Then another star nearer to it in its new position may be 

 used as the mark. 



At first only these notes are to be taken. After the moon has made 

 considerable progress among the stars, inquiries may be started as to 

 what is taking place. Most, if not all the pupils will know that the 

 moon, in common with the sun and the mass of stars, among which 

 they move, rises in the east and sets in the west daily, and they will know 

 that the cause of this apparent motion is the earth's revolution. But 

 most of them will be surprised to find that the moon moves east among 

 the stars. These observations may be carried on and discussed by the 

 pupils until they make out for themselves that this is the motion of the 

 moon around the earth. 



The time of revolution may be determined by noting the date when 

 the moon passes some "fixed star" until it passes it again. 



If the pupils understand circles and degrees, a simple apparatus can 

 be arranged by which they can determine approximately the number of 

 degrees it moves in every twenty-four hours. 



