of the cemetery). But Meigs still demanded that officers be buried on the grounds of the mansion, around the Lees' former flower garden. The first officer burial had occurred there on May 17, but with Meigs' order another 44 officers were buried along the southern and eastern sides within a month. By May 31, more than 2,600 burials had occurred in the cemetery, and Meigs ordered that a white picket fence be constructed around the burial grounds. In December 1865, Robert E. Lee's brother, Smith Lee, visited Arlington House and observed that the house could be made livable again if the graves around the flower garden were removed. Meigs hated Lee for betraying the Union, and ordered that more burials occur near the house to make it politically impossible for disinterment to occur. Meigs himself designed and implemented most of the changes at the cemetery in the 15 years after the war. In 1865, for example, Meigs decided to build a monument to Civil War dead in the center of a grove of trees west of the Lee's flower garden. U.S. Army troops were dispatched to investigate every battlefield within a radius of the city of Washington, D.C. The bodies of 2,111 Union and Confederate dead were collected, most of them from the battlefields of First and Second Bull Run, as well as the Union army's retreat along the Rappahannock River (which occurred after both battles). Although Meigs had not intended to collect the remains of Confederate war dead, the inability to identify remains meant that both Union and Confederate dead were interred below the cenotaph. U.S. Army engineers chopped down most of the trees and dug a circular pit about wide and deep into the earth. The walls and floor were lined with brick, and it was segmented it into compartments with mortared brick walls. Into each compartment were placed a different body part: skulls, legs, arms, ribs, etc. The vault was half full by the time it was ready for sealing in September 1866. Meigs designed a tall, long, wide grey granite and concrete cenotaph to rest on top of the burial vault. The Civil War Unknowns Monument consists of two long, light grey granite slabs, with the shorter ends formed by sandwiching a smaller slab between the longer two. On the west face was an inscription describing the number of dead in the vault below, and honoring