Hemmi? (1)

Back

Slide Back

Well

Note

This mystery rule does not have either the model number or the manufacturer's name on it. I am assuming it is a Hemmi, based on the fact that there is a "PATENT.No.22129" inscribed in the well, and that characters such as π closely resemble those of Hemmi rules.
Other characteristics of this rule include; (1) the Japanese/ Chinese word "Patent" inscribed on the left side of slide is written in an old way; from right to left, (2) the constant table on the back is all in King's English.

What are the model number and approximate year of manufacture? They are very interesting questions. I will certainly try to come up with the answer. In the meanwhile, I challenge you to solve this mystery as well.

This mystery rule was given to me by Zvi Doron. I would like to express my thanks for his generosity.