First of all, RXC, bees, alligators, leaches as well as other live items were inside appropriate packaging containers which were not reused or
specifically returned in the mails when empty for reuse. While primarily introduced for the mailing of day old chicks, Special Handling Service was also used on bee shipments. At first it provided expedited, meaning first class service for parcel post items. After a short period it was expanded to include Special Delivery Service from the office of delivery to the addressee. Previously a separate and additional Special Delivery fee payment was required. But again the live critters were in packaging.
The US Parcel Post was designed for such matter. Tools, coils of wire and other flexible tubular matter, children (under 50 lbs until prohibited), empty milk and cream containers as well as egg crates, samples from broom straws to small metal items, wood (as shown above), paper, fiber stock cut into a postal card, and even fencing are examples of not packaging mailings.
Recently I received an heavy duty metal packing and shipping container for packaging and protecting camera, electronics, musical instruments, glass and other items requiring custom cut foam packaging within a hard-sided container. I have purchased two from different sources and both came empty (except the foam) in the mail with a postage paid label. They are about 30" x 18" x 12" and weighted "empty" as shipped between 5 and 10 pounds.
Years ago my family would buy fruit and other bare root trees which would have the root ball sealed in plastic with the several feet of stem exposed with a mailing tag attached to the stem.
Winter is coming and both Sears and Montgomery Wards mail tires, my mailing tag example was for the mailing of a snow tire.
Below is one of the better sample items I own:
