|Description: A light yellow and golden yellow paper pamphlet giving directions for the use of the slide ruler. “Concise circular slide rules No.28N, Concise Co., Ltd., Edogawa-ku, Tokyo, Japan” is written on the front cover. The book has nine double printed pages with printing in dark blue ink.
History: The St. Lawrence Starch Company was founded in 1889 by John Gray. It was a corn wet-milling operation with the purpose of producing starch and glucose from corn. Many of the product lines produced by St. Lawrence Starch are still in use today such as Durham Starch and Bee Hive Corn Syrup. Food products were only a small portion of the business done at St. Lawrence Starch as starch is an additive in many industrial products such as cement and plastic.
St. Lawrence Starch was located at the foot of Hurontario Street at Lakeshore Road in Port Credit. It was a major industry for this area. The milling operation closed down in 1990 due to competition and high tariffs on corn. In 1993 St. Lawrence Starch announced a marketing alliance with Cargill, Minneapolis, which provides Cargill with exclusive sales services of corn sweeteners and corn starches in the Canadian Market. For more information on the St Lawrence Starch Company, see “St Lawrence Starch 100 Years 1889-1989”.