§ 258. Closing of museum; admission fee during certain hours. The
trustees of any institution supported under this chapter by public
money, in whole or in part, may, so far as consistent with free use by
the public at reasonable or specified hours, close any of its museum
collections at certain other hours, for study, to meet the demands of
special students or for exhibition purposes, and may charge an admission
fee at such hours, provided that all receipts from such fees shall be
paid into the treasury and be used for the maintenance or enlargement of
the institution.