On May 10, 1739, Benjamin Tasker presented the first of numerous petitions to the Maryland Assembly seeking the establishment of a new county to be carved from Prince George's County. Frederick County was created in 1748 and included all of present day Montgomery, Frederick, Washington, Allegheny and Garrett counties. On May 10, 1750, Daniel Dulany conveyed six lots for a Frederick County Courthouse. He was paid 18 pounds. On May 10, 1775, Thomas Johnson of Frederick was appointed to represent Maryland at The Second Continental Congress. On May 10, 1776, Thomas Jefferson spent the night at the Black Horse Tavern on West Patrick Street. On May 10, 1891, the B&O Railroad freight yard opened in Brunswick beginning that town's Boomtown era. The nation's first roundhouse was built in Brunswick. If anyone can add information to these History Moments, or would like to suggest an item for another calendar day, please contact me privately. John W. Ashbury (wasps65@earthlink.net)