Middlesex County was incorporated on May 10, 1643 (Mass Recs 2:38), continuing under successive governments of Massachusetts, most recently the Commonwealth (1780), as outlined in MGLA c 34. Administrative powers and duties previously exercised at various times under the laws of the Commonwealth by the county courts of general sessions of the peace, county courts of common pleas, and circuit courts of common pleas, were assigned to commissioners in Middlesex and other counties, per St 1827, c 77 (1828). The government of Middlesex County in this and other respects was abolished as of the effective date of St 1997, c 48 (approved July 11, 1997)
From the description of Descriptions of railroad locations, 1831-1913. (Unknown). WorldCat record id: 83086260