VINTAGE WEIGHT SLIDE RULE – Hornyak & Kelly - wood slide rule with case

Description

Manufactured & sold by Hornyak & Kelly, Philadelphia, PA, USA
ERA 1960s    Overall length = 14”             Width 2.75”
Scales – 6, printed on, not engraved       Thickness [ Width, Length ] [ Material, Shape ] Weight
Back is blank
Light marks on the finish surface, as if something lifted some of the finish. Does not affect the use of the instrument.
Made of wood. Back & edges have an oil-cloth covering.
Oil-cloth Case shows considerable wear.
This instrument calculates the weight of metal, given the dimensions and shape of a metal part to be produced. The top of the base has a logarithmic scale that gives the thickness of the part in inches. There are two slides. The upper slide has a logarithmic scale of widths (in inches) along its upper edge and a logarithmic scale of lengths (in inches or feet) along its lower edge.
The upper edge of the lower slide has two scales for possible metals, one for lengths measured in inches, one for lengths in feet. The metals are copper, brass, steel, cast iron, lead, aluminum, and water. The lower edge indicates the shape of the piece. The bottom of the base has a logarithmic scale that gives the weight in pounds.