Graphoplex Roplex Circular Slide Rule. 10 Scales. Unique Mechanism. France.Fine.

Description

Graphoplex Roplex Circular Slide Rule.
10 Scales - - 5 each side.
5 -1/8" (128 mm) diameter. ¼" (6 mm) thick.
Metal and plastic.
Duplex.
France.
Has a unique mechanism for operating the scales and cursor.
A knurled metal wheel on one corner moves the scales ("Echelle")
and a second wheel on another corner moves the cursor ("Curseur").
A very fine piece of machinery.
The mechanism is so unique that, to my knowledge, no other slide rule
maker duplicated it.
The Roplex slide rule is scarce and seldom seen.
Rule is in very good condition.
Curseur moves a bit more easily than Echelle.
Case is home made from packing foam sheet. Protects the rule well.
Payment is due via PayPal within 3 days from end of auction.
Buyer pays .70 shipping to USA address
via First Class Package.