Jim here is the M&StL cement hopper purchase history.
1940 buy-new 10 cov hoppers 70051 to 70069 29'-3" 140,000 cement service GA
1947 buy-new 50 cov hoppers 70101 to 70199 29'-3" 140,000 cement service P-S
1955 buy-new 40 cov hoppers 70201 to 70279 29'-3" 140,000 cement service P-S
1956 buy-new 50 cov hoppers 70301 to 70399 29'-3" 140,000 cement service P-S
1957 buy-new 100 cov hoppers 70401 to 70599 29'-3" 140,000 cement service P-S
As you can an early purchase let to major purchase after WWII, then major purchases in the mid 50’s.
The M&StL served two cement plants in Mason City IA, most production going north into Minnesota. Minnesota being one of the few states with out deposits suitable for making cement.
The M&StL also served two cement plants in Des Moines IA, which served the central Iowa area.
