John McGrain processed applications for properties for inclusion into the Maryland National Trust and is a renowned mill historian. The earlier mill was about 30'X 26', one story stone and one of logs with an additional sawmill.

Early records show Brown's Mill at this site in 1794-95. The early mill was built and owned jointly by brothers Richard & Nicholas Brown, both of whom died between 1827 and 1830.

Tax lists show Thomas Brown with a grist and saw mill in 1813. Brown's mill was mentioned in 1820. In 1826, Brown's property with a mill was sold to Richard Ward.

In 1848 Ward's executors sold the property to George Richards Jr. Sometime around 1850 Richards built a new 3 story, frame and stone mill. Richards Mill is shown on a 1862 atlas. In 1871 the Richards Mill property was sold to John W. Abbott for $6025.

Abbott was shown as the proprietor of Deep Run Mill with Samuel Shaner as manager. In 1877, Abbott sold the mill to Shaner for $3800. In 1879 Shaner sold it to Harry H Sparr (Spahr) for $3950. The census of 1880 shows Spahr with a mill having 3 run of stone and a saw mill. Spahr owned the property until about 1900.

Other owners include: Francis L. Herring in 1902, Francis Carroll Herring in 1905, Charles Van Cleaf in 1909, and Mary W. Lee in 1912. The mill remained in the Lee family until it was sold to Ralph S. and Dorothy Walsh in 1958. The next owners were Robert Smith in 1959, Charles I. Rill in the late 1960's, and Thomas V. Appler in 1973.

GPS: 39' 33.02N, 76' 52.29W 620'/189 meters Hampstead Quadrangle