About 1919–1920, Hiram G. Hinckley formed the Watervliet Oil Company, wholesalers and distributors of Sinclair gasoline and other oil products. The company was entirely a Watervliet institution, with all of the stock being owned by local people.
The company purchased a site behind the J. S. Burnside lot on Main Street to build their plant. The Watervliet Oil Company purchased half of the car for the concrete work in connection with the building of their plant from Rosenberg & Forbes. The contractors made good progress in erecting the plant and gasoline storage, with concrete foundations and two 10,000-gallon capacity storage tanks on the location—a healthy increase in capacity for the new company.
Early on, the Watervliet Oil Company had a number of gas stations and garages which were supplied with Sinclair gasoline and petroleum products. These were supplied by route drivers. Charles Camp may have been the first to operate a small tank truck for the Watervliet Oil Company. Other early route drivers were Julius Becker and Will Patterson.
Hinckley moved his office and that of the Watervliet Oil Company into a building vacated by the Electric Service Company in 1925. The following year, H. G. Hinckley reported that the local business had experienced a successful and prosperous 1926. The gasoline and kerosene gallonage as well as all kinds of lubricating oils sold during the year showed a substantial increase over that of any previous year. By this time, the company supplied 20 service stations with Sinclair gasoline and other oil products, in addition to enjoying a large patronage from farmers and other individual business interests in its territory.
Early in 1930, the Watervliet Oil Company made plans for an increase in its bulk storage for gasoline. The storage enlargement was made necessary because of expansion of the business and because of the necessity of carrying large supplies of the different grades of Sinclair gasoline demanded by the trade. Three new tanks of 10,000 gallons' capacity each were ordered—one for H–C Sinclair gasoline, one for Sinclair Aircraft gasoline, and one for distillate.
The Gulf Refining Company, one of the largest manufacturers and distributors of petroleum products, assumed control of the Watervliet Oil Company in 1931. Stockholders in the old company received par value for their stock. The officers of the company in charge of the distribution and sale of Gulf products continued in Berrien and Van Buren County. The officers employed at that time by the Gulf Oil company were Charles Schwarz, president; Will Patterson, vice-president; and H. G. Hinckley, secretary and treasurer.
Shortly after this time, the Watervliet Oil Company seems to have vanished into thin air. No other documentation has been located.
Original source can be found here.