Hemmi 405 Portland Cement Calculations

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Country of manufacture: Japan,            Date of manufacture: Feb 1958 (Date Code = IB)
Overall length: 32.1 cm,          Width: 4.1 cm,           Weight: 121.5 gms
Materials: Celluloid laminate over bamboo, metal end braces, adjustable
Cursor: 3.0 X 5.3 X 1.2 cms; plastic runners, metal framed glass lens, adjustable; lines = single hairline, front and back
Scales: 16, specialized
Front: C₂S(A Scale), CaO [ SiO₂(for C₃S), Fe₂O₃, SiO₂(for C₂S), SO₃, Al₂O₃ ] C₃S, C₂S(B Scale)
Back: C₂F, Al₂O₃ [ Fe₂O₃, C₄AF ] C₃A, SO₃, CaSO₄
Gauge Marks: [      ]
Condition: C3-C4 (Very minimal to minimal signs of use)
Came with: Original red cardboard box/case, instructions
Note: An identical slide rule, owned by Ron Knapp, is clearly labeled 'No. 405' in the location where this specimen has only a date code (IB). That rule is pictured and described on the Oughtred Society's 'Rarieties' page, here: http://osgalleries.org/os/fulldetails.cgi?match=151.

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