Description and Notes:
As stamped on the outer arms, this six inches ten space precision spacing divider is made of stainless steel and made in Japan. This type of dividers is probably devised in the 20th century, as I can not find any reference on which in 19th century or earlier documentations that I have possessed. Also, as mentioned in Drawing Instruments 1580-1980, p. 85, an earlier device of similar function known as the sectograph which is made of brass by Thomas Jones, patented in 1811, was superseded by this precision device. More about the sectograph can be found in Instruments of the Imagination: A History of Drawing Instruments in Britain 1600-1850, p. 11.
The Alvin Company was established since 1950 and this instrument is still in production as of 2010. The following description for the use of this device is given in the company's official website :
Used in forms design, development of models, textile design, etc. Plots 11 equally spaced points. The 11 numbered teeth will always divide the distance between the teeth marked "0" into 10 equal parts. Riveted pivot points expand and contract with ease, yet maintain precise settings. Satin finish stainless steel construction resists wear and corrosion.