In 1879 he entered into a financial arrangement with Lucius Knowles, another pump manufacturer, and their two businesses were formally merged in 1897.

By this time, the company was a nationally leading supplier of a diversity of industrial pumps.

It provided pumps to the United States Army during World War I, nearly doubling the plant size so that it extended from Bent to Monroe Streets.

[2] The surviving elements of the Blake and Knowles are located in East Cambridge, an area that became increasingly industrial as the 19th century progressed.

They are located on a single block about 2.4 acres (0.97 ha) in size, bounded by Third, Fifth, Rogers, and Binney Streets.