Mount Pleasant hospital was, along with Judiciary Square Hospital, one of the two purpose-built hospitals constructed in the winter of 1861-62. These were erected at the urging of the U.S. Sanitary Commission, and designed on the "pavilion principle." [MSHWR, Pt. 3, Vol 1, 917. See this source for a detailed description of the hospital, with a plan of the design.]
An article in the National Republican announcing the start of work on these two hospitals noted that "Both hospitals are constructed on the same plan, furnished by P.B. Wight, Esq. of New York, under the approval of the Sanitary Commission." ["Extensive Hospital Buildings," National Republican, Jan. 7, 1862.]
This hospital was located on Meridian Hill, on the east side of 14th St. Road. It was close to Carver and Columbian College General Hospitals.