"Ever-There Slide Rules" --- 4097, 4097B, 4097C, 4097D, and 4098 (1931-1952):

The "Ever-There" group of slide rules are made of solid celluloid and the scales are engine divided. The scale sets vary between them.The 4097 and 4098 were first shown in the 1931 catalog. In 1936 the 4097 was renamed the 4097B and the 4098 was renamed the 4097C. The 4097D was added to the group and provided an expanded scale set.

The scale sets for the rules are as follows:

4097 & 4097B --- The 4097B is a 5" version of the 4094 and 4096 Merchant's slide rules. The rule was replaced with the 4150-1 in 1954.

4098 & 4097C --- The 4097C is a 5" version of the 4053-3 and was replaced with the 4153-1 in 1952

4097D --- The 4097D has an expanded scale set from the 4097C. It was replaced by the 4161-1 in 1954.

All of these rules have inch and centi-meter scales on the rear side.

Brief History:

The 4097 and 4098 first appeared in the 1931 catalog. The 4097 and 4098 family last appeared in the 1952 price list. The following is a brief history of the 4097 and 4098 family of slide rules as is told in the K&E catalogs that are available at this time. Exact timing is not possible because of the time between catalogs.

Catalog Page Links:

Links to catalog pages for the "Ever-There" family of slide rules:

Link to scans of "Ever-There" Slide Rules