Chemical Match Output

Number:23b

Maker:Lawrence Engineering Services Molecular Ratio Slide Rule (for Portland Cement calculations?)
PHOTO

Length: 26.7 cm

Gauge Marks:

Scales Front: Di₁ [ SiO₂, Al₂O₃, Fe₂O₃, CaO, M.R. ] D₂

Scales Back: Instructions

Info: Steve Seale Collection