50 FIRST YEAR COURSE IN GENERAL SCIENCE 



nations will help us in remembering the units of the 

 metric system. 



10 mills make 1 cent. 



10 cents make 1 dime., 



10 dimes make 1 dollar. 



We use the dollar as our unit and regard the smaller divi- 

 sions as fractions which can always be expressed decimally. 

 It is not necessary to write the names of the parts, for the 

 dimes, cents, and mills are expressed decimally. 



I 



cm. 



Inches 



FIG. 15. ENGLISH AND METRIC MEASURE 



1. What is the equivalent of 1 in. in centimeters? 2. How many 

 millimeters in 1 in.? 3. From the answer to 1, find which is longer, a 

 yard or a meter. 



47. Measurement of Extension. In measuring length 

 by the metric system, the meter is the unit. Its divisions 

 are thus expressed: 



10 millimeters (mm.) make 1 centimeter (cm.). 



10 centimeters make 1 decimeter (dm.). 



10 decimeters make 1 meter (m.). 



10 meters make 1 dekameter (Dm.). 



10 dekameters make 1 hectometer (Hm.). 



10 hectometers make 1 kilometer (Km.). 



The prefixes square and cubic are used in measures of sur- 

 face and volume respectively. A block measuring 5 centi- 

 meters on each edge has on each side a surface of 25 square 

 centimeters, and contains 125 cubic centimeters. 



The number of meters is more commonly written than 

 the words dekameter and hectometer, but the kilometer (one 



