CORNELL 



R\iral ScKool Leaflet 



SUPPLEMENT FOR THE CHILDREN 



Published monthly by the New York State College of Agriculture at Cornell University, from 

 September to May and entered as second-class matter September 30, 1907, at the Post Office 

 at Ithaca, New York, under the Act of Congress of July 16, 1894. L. H. Baiicy Director 



ALICE G. McCLOSKEY, Editor 

 Professors G. F. WARREN and CHARLES H. TUCK, Advisers 



Vol. I. 



ITHACA, X. v., FEBRUARY, 1908. 



No. 6 



WHY IT SNOWS IN WINTER AND RAINS IN SUMMER 



By W. M. Wilson 



OW many boys and girls remember that in our 

 last lesson we changed the water in the teakettle 

 into vapor or water gas by the heat of the fire, 

 and then changed it back into water by using a 

 cold glass? We thus proved that water exists in 

 two forms — as a liquid which we can see, feel, 

 and taste, and as a gas which we can neither see, 

 feel, nor taste. 



There is still another form of water, and 



that is the form we see most frequently in the 



winter time. Can you tell what this form is ? If 



you place a dish of water out of doors on a cold 



night, what will happen to it? Try this, and you 



will then know that water exists in three forms, — 



as a solid, (ice), as a liquid (water), and as a gas (vapor). Can you 



think what it is that causes the same thing (water) to be a solid at one 



time, a liquid at another, and a gas at another? 



Water begins to change to ice when it is cooled to a temperature of 32 

 degrees by the Fahrenheit thermometer. Fahrenheit is the name of the 

 man who in^vented the kind of thermometers that are most generally used 

 in this country. Ask your teacher to show you a thermometer and point 

 out the freezing point of water which is 32 degrees above the zero mark 

 on the scale. 



If you want to know whether your thermometer is correct or not, 

 you may easily test it by taking a pailful of snow and putting in enough 

 cold water to make it slushy. Then stir the slush with the thermometer 

 for a few moments. If the thermometer reads exactly 32 degrees, it is 

 correct. 



When we changed the moisture or vapor in the air to water by using 

 a cold glass, the temperature of the air in the room was above the freez- 



7Z^ 



