Diamond Plate Glass Company

The Turning Point

The Gas Boom brought about an economic revolution in Indiana during the late 1800s. The Diamond Plate Glass Company played a pivotal role in those changes. When a huge natural gas reservoir was discovered under east-central Indiana, local communities seized the opportunity. Many communities, including Kokomo, offered free natural gas in return for business development.

In 1887, Monroe Seiberling, Colonel A.L. Conger, and a group of investors from Akron and Chicago saw a unique opportunity in Howard County on the far western edge of the gas reserve. Chicago was undergoing an architectural expansion because of new construction techniques that allowed for taller buildings with larger windows. The investors saw Kokomo’s easy railroad access to both the raw materials of glass-making including sand from the southern shores of Lake Michigan and to the markets of Chicago. This coupled with a source of cheap and seemingly unlimited energy to fire the glass-making kilns. Kokomo offered them free gas, free land, plenty of water for the boilers, and a railroad spur that linked directly to the factory site.

When they began making windows in the summer of 1889, the Diamond Plate Glass Company was said to be the largest plate glass factory in the country. Seiberling believed it to be the largest in the world. It employed up to 1800 men, who worked in hot, dirty, dangerous conditions for 60 hours a week. By the end of the year, the company had eight gas wells, leases on 4000 acres of the gas field, and plans to make the factory even larger. In December, they made the largest sheet of plate glass ever cast at the time – roughly 10 feet tall and 17 feet wide.

The plate glass factory marked the leading edge of an economic and population expansion that soon hit a wall. The national financial Panic of 1893 caused an economic depression with serious international repercussions. There was a sudden decrease in demand for plate glass and prices hit rock bottom. At the same time, it was becoming obvious that the gas fields were drying up, and with them the cause of the boom. Diamond Plate ended up in a battle with Pittsburgh Plate Glass, and was absorbed by them in 1895.

The Kokomo plate glass factory continued operation, now powered by coal, until it was phased out in 1930. During World War II, General Electric used the site to manufacture electric motors for naval vessels. Cuneo Press, the world’s largest commercial printer, began producing nationally-distributed magazines there in 1949, but fell on hard times in the late 1970’s. In the years since, the plate glass site has been used off and on for warehousing.



1201 E. Vaile, Kokomo, IN 46902