The St. Louis directory and register :
Section VI.

1. The senators and representatives shall receive a compensation
for their services, to be ascertained by law, and paid out of the trea-
sury of the United States. They shall, in all cases, except treason,
felony, and breach of the peace, be privileged from arrest, during
their attendance at the session of their respective House, and in
going to, or returning from the same; and for any speech or de-
bate in either House, they shall not be questioned in any other
place.

2. No senator or representative shall, during the time for which he
was elected, be appointed to any civil office, under the authority of
the United States, which shall have been created, or the emoluments
whereof shall have been increased, during such time; and no per-
son, holding any office under the United States, shall be a member
of either House, during his continuance in office.