Surface Machinery and Methods for Oil-Well Pumping

BUREAU OF MINES
I a d"."T *

BULLETIN 224 PLATE XII

A. COUNTERBALANCE, a, ATTACHED TO WRIST PIN OF BAND-WHEEL
CRANK ARM

B. COUNTERBALANCE ATTACHED TO BEAM

George, H. C. Surface Machinery and Methods for Oil-Well Pumping. Washington D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc12407/. Accessed August 20, 2014.