The Secretary of the Interior is authorized, in his discretion and upon submission of evidence of title satisfactory to him, to accept on behalf of the United States of America that certain tract of land adjoining the Hot Springs National Park, Arkansas, described as being a part of the north half southwest quarter section 27, township 2 south, range 19 west, west of the ninety-third meridian, in Garland County, Arkansas, and which has been tendered to the United States of America as a donation and as an addition to the said Hot Springs National Park: Provided, That such land when accepted by the Secretary of the Interior shall be and remain a part of the Hot Springs National Park.