Pub. L. 83-763, tit. VI, sec. 604

Sec. 604. The Act entitled “An Act authorizing the employment of mail messengers in the postal service”, approved March 3, 1887 (39 U. S. C., sec. 578), is amended by adding at the end thereof the following new paragraph: “The Postmaster General may, in his discretion and under such regulations as he may prescribe, readjust the compensation of the holder of any contract for the performance of mail-messenger service on account of increased or decreased costs occasioned by changed conditions which could not reasonably have been anticipated at the time such contract was made.”