Beginning with the Mishna on yesterday’s daf (12b), the focus in our perek is on what to do what you find a shetar – a legal document – which contains information about a transaction between two people. Since it is not clear who was holding the shetar when it was lost, it is unknown to whom it should be returned; perhaps, it cannot be returned to either of them.
One position that is presented on our daf is the opinion of Shmuel, who follows Rabbi Meir in ruling that a promissory note that does not contain ahrayut nekhasim – it is not guaranteed with real estate – cannot be collected, neither from property that was in the borrower’s possession at the time of the loan, nor from any other source. Thus, such a note can be returned to the lender whose name appears on the note, since it will not be collected in any case.
The Gemara asks that if the note is worthless, why would there be any point in returning it? Rabbi Natan bar Oshaya explains that it can be used “la-tzor al pi tzlohito – used to stop up a flask.”
In the ancient world, which was, generally speaking, poorer in terms of physical resources than the modern world, any object, no matter how small or insignificant, was used to its fullest extent. The tzlohit – the flask – discussed here was a utensil, usually made of clay, with a narrow neck and small opening used for storing liquids like wine or oil. Most clay vessels were made with matching covers from the same material that would be used to protect the integrity of whatever was stored inside. Tzlohiyot were an exception, and covers were not always made for them, so when they needed to be closed any available material suitable for that purpose was used.
In this context it is worth noting that the “paper” of those days – which was actually a type of papyrus – was much stronger than what we use today, which is why is could have been used to stop up a flask and protect its contents. Nevertheless, this was certainly a minor use of the material and its value – even in those days – was minimal.