In pursuance of this contract between the United States of the one part and Maryland of the other part, expressed in solemn statutes, the present seat of government was occupied in November, 1800, when Congress proceeded to assume that complete jurisdiction conferred in the Constitution, by enacting, on the 27th of February, 1801, “that the laws of the State of Maryland, _as they now exist_, shall be and continue in force in that part of the said District which was ceded by that State to the United States, and by them accepted for the permanent seat of government.”[230] Thus at one stroke all existing laws of Maryland were adopted by Congress in gross, and from that time forward became the laws of the United States at the national capital. Although known historically as laws of Maryland, they ceased at once to be laws of that State, for they draw their vitality from Congress alone, under the Constitution of the United States, as completely as if every statute had been solemnly reënacted. And now we see precisely how Slavery obtained its foothold. Among the statutes of Maryland thus solemnly reënacted in gross was the following, originally passed as early as 1715, in colonial days. “All negroes and other slaves already imported or hereafter to be imported into this province, and all children now born or hereafter to be born of such negroes and slaves, shall be slaves during their natural lives.”[231] Slavery cannot exist without barbarous laws in its support. Maryland, accordingly, in the spirit of Slavery, added other provisions, also reënacted by Congress in the same general bundle, of which the following is an example. “_No negro or mulatto slave_, free negro or mulatto born of a white woman, during his time of servitude by law, … _shall be admitted and received as good and valid evidence in law, in any matter_ or thing whatsoever depending before any court of record or before any magistrate within this province, _wherein any Christian white person is concerned_.”[232] At a later day the following kindred provision was added, in season to be reënacted by Congress in the same code. “No slave manumitted agreeably to the laws of this State … shall be entitled … to give evidence against any white person, or shall be recorded as competent evidence to manumit any slave petitioning for freedom.”[233] And such is the law for Slavery at the national capital.