[Volvelle]: Today's gasoline is Today's engines give you 50% more work than the gaoline of 1925 would deliver in 1925 engines... That's why we say 2=3

$20 · Offered by Between the Covers

[No place]: Ethyl Corporation, [circa 1952]. Unbound. Volvelle. Measuring 5½" in diameter. Modest foxing, very good; the inner circle turns smoothly. More

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