72 NATURE-STUDY REVIEW [13:2— Feb., 1917 



the light coming from one direction can only light half of the ball 

 at a time. If the light is on the same side of the ball as we are, 

 we see all of the ball facing toward us lighted, which is comparable 

 to the full moon, but if the light is at one side we see only a part. 

 Thus can be shown the full moon, the last quarter, the old moon 

 crescent, the dark of the moon, the new moon crescent, the first 

 quarter, and back to the full moon, simply by moving the light 

 around the suspended ball. The experiment on p. 921-22 is too 

 complicated for the third grade, but with the earth eliminated, 

 Obs. 1-6, p. 922 suggest what shall be shown. The story "A 

 Visit to the Moon," p. 919 should be read, or, what is better, 

 told in simpler terms to fit third grade intelligence. By asking 

 the questions on Obs. 18-29 on p. 923 a few at a time and talking 

 over the answers with the pupils, a very fair start may be made in 

 knowledge of our earth's one satellite. 



The Dog. — The dog and his habits can be better understood 

 by comparing him with the wolf which he resembles in form and 

 habits and by contrasting him with the cat which he does not 

 resemble either in appearance or habits. Obs. 1-3, p. 265 form 

 the first lesson, Obs. 4, 5, 6 the second, Obs. 7, 8 the third, 9 the 

 fourth, 10 the fifth, 11 the sixth, and 12 the seventh. The pupils 

 should be encouraged to read all the dog stories adapted to their 

 abilities. See supplementary^ reading, p. 267. 



The Cat. — Puss is a very interesting animal and just at present 

 her status as a member of the community is by no means settled. 

 Times have changed since the days of Dick Whittington when a 

 cat was worth her weight in gold. It is only through statements 

 of history you can come to appreciate the economic importance of 

 cats. Wherever pioneers have planted their crops, rats and mice 

 have followed in abundance to help in the harvest. Therefore 

 our forefathers especially prized the cat which helped them to save 

 their grain from these marauders. The cat is still an important 

 factor in keeping rats and mice in check. Our government 

 appropriates money every year to support cats in the post offices 

 and other public buildings. However, at present the whole 

 economic question of bird preservation is before us and the cat 

 is surely an enemy to birds. We should at least demand that all 

 cats be licensed by their owners and that all stray cats be elimi- 

 nated. Obs. I, 2, p. 272 form one lesson; Obs. 3, 4, 5, p. 273 

 suggest material for another lesson; 6, 7, 8, 9 another; 10, 11 



