Hartman, Gertrude. <br/><br/>
Machines and the men who made the world of industry 
by Gertrude Hartman. 
 - New York  The Macmillan company  1939. 
 - x p. , 1 b., 278 p.  illus., diagrs.  22 cm. 
<br/><br/> Illustrated lining papers. 
<br/><br/><label>LCCN: </label>39025154  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Industrial arts--Juvenile literature.<br/>Inventors<br/>Machinery--Juvenile literature.<br/>Industrial arts--History.
<br/><br/><label>LC Class. No.: </label>T15  / .H347 
<br/><br/><label>Dewey Class. No.: </label>609