Engineering Equipment Appraisal

Edison Steam Pressure Gauge with Siphon Tube and Mount

This item is an antique or vintage steam pressure gauge manufactured by Edison. The gauge features a circular brass casing with a cream-colored face, marked with numbers 5 through 30 in increments of 5, and smaller tick marks for individual units. The '15' marking is prominently centered at the top. The gauge face clearly displays 'Edison Steam Gauge' and 'Edison Lamp Works' or similar text, indicating its manufacturer. A single needle, likely made of brass or a similar alloy, points to the pressure reading. The brass casing shows significant patina, consistent with age and exposure, suggesting a rich golden-brown hue with some tarnishing and possible discoloration in areas. There are no obvious dents or severe damage to the casing, though surface scratches and minor wear are present. Below the gauge, a brass pipe extends downwards, connecting to a classic siphon or pigtail tube, which is a coiled, U-shaped tube designed to protect the gauge from hot steam by allowing condensate to collect and cool the steam before it reaches the sensitive internal mechanisms. This siphon tube is also made of brass and exhibits a similar aged patina. The entire assembly is mounted on a hexagonal, flat brass base with three visible mounting holes, indicating it was originally fixed to a surface. The connection points between the gauge, siphon, and base are threaded and appear robust, though some minor corrosion or oxidation is visible around the joints. The overall construction points to industrial or maritime use, reflecting a period when steam power was prevalent. The craftsmanship appears sturdy and functional, typical of instrumentation from the late 19th to early-to-mid 20th century. The item exhibits good visible condition for its likely age, retaining its primary components and legibility.