A Story Outline of Evolution 



in some dry substance was the beginning of this cycle of 

 developing heat that ends in the grate before you, where the 

 ''spirits" of the earth's interior are being changed into an 

 agency of convenience and comfort. 



On the mantelpiece there is another instrument. It is a 

 clock that is measuring the days and nights into hours, 

 minutes and seconds. The year is measured by the time it 

 takes the earth to complete one revolution in its orbit around 

 the sun. The month is measured by the time required for 

 the moon to revolve around the earth and the day is meas- 

 ured by the time required for the earth to make one com- 

 plete revolution on its axis. We thus see that the longer 

 periods of time are measured by the movements of the 

 heavenly bodies. But as our civilization began to become 

 complex, the necessity for shorter divisions of time pre- 

 sented itself. 



Perhaps the earliest effort made by man in solving this 

 problem was in the use of the sun-dial, or shadow clock, but 

 like the early attempt at communication by the signalling 

 system, the sun-dial was useless at night and on cloudy days. 

 Next came the fire clock, the water clock and the hour-glass. 

 The Chinese, Greeks and Romans used the water clocks and 

 during the Middle Ages the weight clock came into use. The 

 next step in the evolution of the clock was the use of the 

 pendulum. It will thus be seen that our modern clock has 

 passed through a cycle of centuries in its development. 



If we shall examine the bathroom, we will find beautiful 

 bathroom fixtures where clear, sparkling water may be had 

 by the simple process of turning a faucet. It comes to you 



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