In honour of spring I thought this topic seemed timely… The schematic drawings by Maxwell Sachs, filed Dec 11, 1951 and approved October 1954, are for the Spring-o-lator mule – a huge fashion hit in the mid 1950s. As shown on the drawings, between the ball and heel of the insole was a bridge of elastic tape that would stretch, sucking the shoe up to the bottom of the foot via the tension of the stretched elastic. American shoe designer Beth Levine (wife of shoe company owner Herbert Levine) was shown the drawings by Maxwell Sachs. He had no practical application in mind for his invention, although he thought it might be useful as an orthopedic insole. Beth Levine realized its potential for keeping high-heeled mules in place. She called her fashion sandals “magnet-socks” and demonstrated a pair at a shoe convention by running across the lobby while wearing a pair.
Herbert Levine shipped thirty-six pairs to each of three stores in Boston, Chicago and Los Angeles for test marketing and within days they were sold out. The Los Angeles store immediately re-ordered but cancelled the following day because other manufacturers were already knocking off the mule. The patent holder had ignored a verbal agreement with Herbert Levine for a six-month production exclusive in exchange for the magnet-sock idea. Sachs registered the name spring-o-lator and made the patent available for production to anyone willing to pay a royalty. The shoes were in production even before the patent was approved, and if you look carefully at the writing in spring-o-lators, some will say ‘patent pending’, while others will give the patent number, which is awarded after a patent is approved. The fashion lasted from mid 1954 until 1958, and then slowly fell off in popularity when the pointed toe came into fashion.