Up, down, or open-moving machines

Name: Up, down, or open-moving machines
Author: Michele Spirn

Cover of Up, down, or open-moving machines

Discusses how simple machines work using drawbridges, escalators, and retractable roofs as examples.

Simple machinesJuvenile literatureMachine designHistoryReaders (Elementary)Readers (Primary)Machines simplesOuvrages pour la jeunesseMachinesConception et constructionHistoireAnglais (Langue)