[2] In 1892, the company commissioned the architecture firm of De Lomos & Cordes to build a showroom and offices at 127 Fulton Street in Manhattan.

[1] In the first decade of the 20th century, Keuffel and Esser introduced a new line of surveying instruments based on the work of John Paoli, an Italian immigrant in Hoboken.

[4] K&E acquired instrument maker Young & Sons of Philadelphia in 1918 and made it a department of the firm, retaining the brand name for a time.

It was one of the main suppliers to major engineering firms in Québec during the thriving years of the late sixties, when the province was booming with construction activities, building highways and preparing for Expo 67.

In 1959 a division was formed to specialize in the development and manufacture of optical, mechanical, and electronic systems for precision measurement of lengths and angles.

[8] During World War II, the company made fire-control instruments for the US government and won seven Army-Navy "E" Awards for Excellence in Production.

[10] Around 2005, this collection (which had been acquired by successor companies) was donated to the MIT Museum (Cambridge, Massachusetts), greatly expanding their existing holdings.