Mannheim slide rule
Date: 1915-1930
Inventory Number: 2003-1-0252
Classification: Slide Rule
Dimensions:3.6 × 26 × 1.3 cm (1 7/16 × 10 1/4 × 1/2 in.)
DescriptionRectangular wooden rule faced with white celluloid. The top and bottom slides are fixed; the center slide moves left and right and is removable. A glass runner with a vertical line down its center also moves left and right.
The fixed portion of the slide rule is printed with two scales. Along the bottom edge of the top slide is an unlabeled scale consisting of two logarithmic scales (values ranging from 1 to 10) placed side-by-side. Along the top edge of the third slide is an unlabeled logarithmic scale carrying values from 1 to 10.
The face of the moveable slide is printed with two scales. The unlabeled scale along its top edge is identical to the top scale on the fixed portion of the rule. The unlabeled scale along its bottom edge is identical to the bottom scale on the fixed portion of the rule.
The back of the moveable slide is printed with three scales. The top scale, "S", carries values from 35' to 90°. The center scale, "L", has values descending from 10 to 1. The scale along the bottom edge of the back of the slide, "T", has values ranging from 5.5 to 45.
Printed along the top edge of the rule is a 10-inch scale, part of which has chipped off. Along the bottom edge of the rule is a 25-centimeter scale, part of which has chipped off. Underneath the the removable slide is a centimeter scale carrying values from 26 to 51.