Presents over 600 entries describing inventions and scientific discoveries and the people responsible for them.spring was joined with a mainspring-driven clock to create a precise and completely portable watch, suitable for ships as well as a persona#39;s wrist. ... These early battery clocks used tiny motors to wind the mainspring when it ran down. The realanbsp;...
|Author||:||Linda Schmittroth, Mary Reilly McCall, Bridget Travers|
|Publisher||:||Gale Cengage - 1995|