Born in New Haven, Connecticut, in 1787, he served in the New York Militia during the War of 1812.

Dummer joined his brother George Dummer's Jersey Glass Company on Washington Street between Essex Street and the Morris Canal in Paulus Hook (later became incorporated as Jersey City).

He later obtained a patent for the manufacture of pressed glass by a process called "Dummer's scallop or coverplate."

Dummer & Company and was selling glassware for home, decorative and commercial use.

After his company went out of business, Dummer was elected City Collector of Taxes, and afterwards appointed Deputy collector of customs of the Port of New York, by Abraham Lincoln and re-appointed under Ulysses S. Grant.