SUN AND MOON. 179 



make good lessons out of such commonplaces even as tying 

 knots. This is not an argument in favor of teaching Nature 

 Study lessons on subjects that are not "worth while." When 

 there is so much to choose from, there is no need to give a 

 single worthless lesson. But the title of a lesson does not tell 

 its merit ; a topic that may be valuable in one teacher's hands 

 may be worth little in another's. 



Sun and Moon. — That the Sun is our chief source of light 

 and heat, and that it remains above the horizon longer and 

 shines more nearly vertically in summer than in winter is 

 about all that can be taught of it in the public school by 

 direct observation. Its disc may be looked at through dark 

 brown or smoked glass ; sometimes there are spots on its 

 surface large enough to be thus made visible to the eye. 

 A good deal may be done with the shadow cast by a 

 fixed or definitely placed object as the angle of a window 

 frame 1 ; even the imaging of the ecliptic can be taught to an 

 advanced class by reasoning from the observed westerly 

 progress of the stars. For a lesson on the use of a " shadow- 

 stick" see pp. 182-4 of "Public School Nature Study." 



In the study of the Moon there are a few facts that must be 

 given by the information method, such as that the moon shines 

 by reflected light and that its path passes monthly between us 

 and the sun. Working from these facts excellent lessons may 

 be taught by observation, including the period of time and 

 direction of the moon's circuit, and its monthly swing from 

 tropic to tropic. Evening after evening the changes of its 

 position relative to observed stars may be noted and inter- 

 preted as its easterly motion by children even as young as 

 those in the Second Form. In the book last named there 

 are directions for observing the lunar motions and phases. 



1 Poising a drain tile or a square box, without ends, parallel to the sun's rays on a 

 horizontal sheet of paper, and drawing the inside shadow line at different times of the 

 day, and at the same time of day in different seasons of the year, will show the 

 scattering of light and heat due to obliquity of the rays. 



