Thanks for the welcome to the group. I have a question. I have been
offered a TACHET 19th century all-wood slide rule. I think it is
French but who knows. It is a simplex 3 stator-2 slide design with
the third stator separating the two slides. There is no cursor and I
suspect it was not designed to have one. Ther appear to be rear
index windows, one for each slide, at the left end of the rule,
leading me to suspect that the slides are duplex and non-reversable.
On the reverse of the rule is a table of formulae and equivalents in
the European and American pre-duplex fasion. Unfortunately, the
pictures I have are sufficiently blurry that I cannot make out
individual scales or the exact nature of the formulae. I can find no
reference to Tachet in any of my texts. Has anyone heard of this
rule? Does anyone have an idea about a fair price? Thanks in
advance.
Grant Hutchinson