Scientific American Monthly

Scientific American Monthly

4.11 - 1251 ratings - Source

They like to be as nearly certain as possible that any new machine they buy will return a good profit. ... Figures obtained from tractor owners as to the number of days they use their machines for different kinds of work and as to the total number anbsp;...

Title:Scientific American Monthly
Author:Alexander Russell Bond
Publisher: - 1920


You Must CONTINUE and create a free account to access unlimited downloads & streaming