A contradiction is brought between our mishna and a braita about whether or not an employer can insist that the worker takes his wages in the items he is working with rather than in money. Rav Nachman brings 3 different explanations (as the first two are rejected) to explain the contradiction. From this the gemara discusses whether or not one can acquire items from hefker by watching them (without lifting them). If one puts items in the public domain, how long can they be left there? Even if one is allowed to leave them there by law, if they damage another is the person wh left them responsible to pay for damages? If a group of people work together – each doing a different part of the work – to build something and after it is built, it breaks and damages someone, which one is responsible to pay? If one field is higher than another and something grows from the side of raised area that borders the two fields, to whom does it belong? In many ways the end of the masachet mirrors the beginning.