Mechanical movements, powers and devices; a treatise describing mechanical movements and devices used in construcive and operative mechinery and the mechanical arts, being practically a mechanical dictionary (1917)
Hiscox, Gardner Dexter, 1822?-1908 · New York : The Norman W. Henley publishing co. · leaf 27
14. Bell Crank or Angular Lever, firstorder. Same notation as No. 11. … 15. Bell Crank or Angular Lever,second order. Same Notation as No. 12. 16. Bell Crank or Angular Lever,third order. WX 0 + ( a X cosine of a nglej =P
Mechanical movements
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