10-inch Mannheim Adjustable Slide Rule
Frederick Post model 1449 [1936-40]
Hemmi model 43
Appears in 1936 Catalog and Price Lists through 1940

Thin 10-inch Mannheim Adjustable Slide Rule
Frederick Post model 1449T  [1937-40]
Hemmi model 47
Appears in 1937 and 1940 Price Lists (not shown)

 1449 (left)           1449T (right)
Edge picture shows both rules 

Top edge: Slanted 0-10 inches
Bottom edge: Vertical 0-28.5 cm
Back of slide: [S, L, T]
Back of rule: Plastic Table
 


This page is from the 1936 (18th Edition) Post Catalog 
The term "adjustable" is carried over from the previous catalog in error; 
Hemmi rules did not have a friction adjusting mechanism other than the 
usual bend-able metal back plate.

Model 1449T first appeared as a "New Item" in the 1937 Post price list where it was described thusly: "MANNHEIM SLIDE RULE.  10 inch, like No. 1449 but thin model, in fabricoid case with instructions.  Each   $3.50."  (There was also a model 1449TL in sewed leather case for $4.25.)