20 Commercial papers
ADMISSIBLE DOCUMENTS
Bills of lading
Copies of or extracts from deeds under private seal written on stamped or unstamped paper
Documents of all kinds drawn up by
public officials
Invoices
Manuscripts of works or for newspapers
sent unaccompanied
Musical scores or sheets of music in
manuscript
Out-of-date correspondence (unclosed letters and postcards) which has already fulfilled its original purpose, and copies thereof
Papers of legal proceedings Proposals and policies of insurance and formal papers necessarily incident to insurance
Pupils' exercises in original or with cor- rections, but without any note which does not relate directly to the per- formance of the work
Receipts
Statements of accounts Way bills
Exceptionally, correspondence exchanged between students at school, even when it is current and personal, is admitted at the commercial papers rate, provided that it is sent through the intermediary of the principals of the schools concerned.
Documents may be accompanied by reference slips or covering statements showing the following or similar particulars: a list of the papers included in the packet; references to correspondence exchanged between the sender and the addressee.
INADMISSIBLE ARTICLES
Postage stamps or forms of prepayment, whether cancelled or not, or any paper representing a monetary value, are inadmissible; but out-of-date correspondence may bear cancelled postage stamps or franking impressions which served to prepay the original postage.
PACKETS CONTAINING PRINTED MATTER, COMMERCIAL PAPERS AND SAMPLES
It is permissible to enclose in the same packet printed matter (except literature for the blind), commercial papers and samples, see under heading "Printed Papers".