Tannenbaum, Beulah <br/><br/>
Understanding time :  the science of clocks and calendars / 
Beulah Tannenbaum and Myra Stillman ; illustrated by William D. Hayes. 
 - New York :  McGraw-Hill,  c1958. 
 - 143 p. : ill. 
<br/><br/> Includes index. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Time<br/>Clocks and watches<br/>Chronology