The lesser known Keystone Evaporator was a product of Sproul Hardware and Manufacturing Company out of Delevan, New York. James B Sproul & Sons opened a hardware store in Delevan, New York around 1902 and along with hardware goods they began manufacturing maple sugar equipment including evaporators of various sizes and syrup finishing rigs.
Prior to settling in the Delevan area, Sproul and his family tried their hand at farming for a few years in Ashtabula, Ohio and before than he was in the dry goods business in Springs, Pennsylvania. Both of J.B. Sproul’s two sons, Clyde Robert Sproul and James Fay Sproul, were a part of the hardware and manufacturing business from its very beginning and carried the manufacturing portion of the business forwards after the death of their father J. B. Sproul in 1917.
In 1909 Sproul & Sons expanded their production operations, constructing a new building in Delevan specifically dedicated to manufacturing maple sugaring evaporators. At that time, they also posted advertisements in the Buffalo, NY area looking for experienced “tinners”.
The primary product of their maple sugaring manufacturing efforts was called the Keystone Evaporator, which was a flat-bottomed set up with multiple pans on an iron arch. A particularly unique feature of the Keystone Evaporators was a series of horizontal tubes built into the back pan to serve as a kind of sap pre-heater. The smaller model called the Keystone Junior featured vertical tubes in the rear pan that were referred to as a cupped heater.
In the 1930s, the Sproul Manufacturing Company added another evaporator to their line up which they called the Cyclone Evaporator that featured a back pan with deep flues, a middle pan with shallower flues, and a flat-bottomed front or syrup pan.
Sproul Manufacturing offered a full-complement of maple sugaring supplies and equipment including the Vermont sap spout made by the Vermont Evaporator Company and patented by Willis. They produced their own sap gathering and storage tanks and their special Keystone sap pail. The sap pail cover they offered was made in the design patented by Augustus H. Todd of Griffin’s Corners, New York.
By 1915, J.B. Sproul appears to have retired from the business and left it in the hands of his sons. In 1916, they sold the brick and mortar hardware store and the two sons instead focused their attention on manufacturing sugaring equipment. This continued through the 1920s, 1930s, and into the 1940s.
It is not clear when exactly the Sproul Manufacturing Company stopped manufacturing and selling evaporators, but it was probably sometime in the mid-1940s. The older of the two sons, Clyde R. Sproul, passed away in 1946 and it appears that the company was transferred to bank ownership in 1950. The younger son Fay Sproul himself passed away in 1957.
