K&E 4097 & 4098 Family of Slide Rules

4097 --- 5" Version of the 4094 and 4096 Merchants Slide Rules. First shown in the 1931 catalog.

Scale set: CF = CF CI C = D

4097B --- Replaces the 4097 in 1936. The same as the 4097 except for the cursor.

4097C --- Replaces the 4098 in 1936. The same as the 4098 except for the cursor. This is a 5" version of the 4053.

4097D --- First shown in the 1936 catalog. The scale set is a combination of the 4097B and 4097C. It is the predecessor of the 9061 and 4161-1.

4098 --- This is a 5" version of the 4053. First shown in the 1931 catalog.

4098A --- This is a 5" version of the 4041. First shown in the 1936 catalog.