I bought this Tinkertoy set at a fleamarket last week. I had never seen it before but checking Wikipedia I came up with this:
'The Tinkertoy Construction Set was created in 1913. It was designed by by Charles H. Pajeau and Robert Pettit after seeing children play with pencils and empty spools of thread.
The cornerstone of the set is a wooden spool roughly two inches (5 cm) in diameter with holes drilled every 45 degrees around the perimeter and one through the center. With the differing-length sticks, the set was intended to be based on the Pythagorean progressive right triangle.'
Unfortunately, this set isn't complete.