What is a simple machine?
Darby, Gene.
What is a simple machine? By Gene Darby. [contracted braille] / - Louisville, Ky. : American Printing House for the Blind, 1969. - 1 v. of contracted braille. - The What is it series .
Contracted braille.
Describes simple machines--the wedge, screw, wheel, inclined planes, pulley, and lever, and shows how they work.
Transcribed from: Chicago : Benefic Press, 1961.
Simple machines--Juvenile literature.
531.8 DAR
What is a simple machine? By Gene Darby. [contracted braille] / - Louisville, Ky. : American Printing House for the Blind, 1969. - 1 v. of contracted braille. - The What is it series .
Contracted braille.
Describes simple machines--the wedge, screw, wheel, inclined planes, pulley, and lever, and shows how they work.
Transcribed from: Chicago : Benefic Press, 1961.
Simple machines--Juvenile literature.
531.8 DAR