WATER 143 



calories of heat. How much heat will be given out when 

 one gram of steam is condensed? 



96. Three States of Water. Water at ordinary tem- 

 peratures is a liquid. The liquid can be changed into a 

 solid by freezing. While water is freezing, heat is being 

 taken from it. Heat is required to melt ice, hence ice 

 is valuable for refrigeration. Liquid water can be changed 

 to a gas by the addition of heat. The gas is called steam. 



97. Water and Climate. Except hydrogen, water 

 has the highest specific heat of any substance and so a 

 large quantity of heat is required to increase the tempera- 

 ture of inland lakes and seas. The water once heated 

 requires a long time for the heat to escape. On account 

 of this property of water, lakes do not change their 

 temperature suddenly and so they do not vary in 

 temperature very much throughout the entire year. 

 For this reason large lakes and inland seas affect the 

 climate of the country .around them: the summers are 

 not so hot; the spring season comes rather late; and the 

 autumn is temperate. On account of the constancy of 

 the climate, regions around large bodies of water are 

 usually healthy places in which to live. Blossoming fruit 

 trees in the springtime are less apt to be frozen if they 

 are near a large body of water. 



Ocean currents have great influence upon the climate of 

 various parts of the earth. The Gulf Stream, flowing 

 out of the Gulf of Mexico across the Atlantic Ocean to 

 Europe, makes the climate of Western Europe mild and 

 unchangeable. The Japan current, coming across the 

 Pacific Ocean, touches the western shores of North 

 America and makes a tropical climate in Southern Cali- 

 fornia and a very mild temperate climate in Washington 

 and Oregon. The climate along some coasts, such as 



