We discussed in the fourth perek (chapter) that there are instances where somebody can own a well that is under a different person's home. He has the path that goes to that well with it in his friend's property. He has access to the well. Here are other halachot (Jewish laws) associated with him accessing that well.
Somebody has a well inside his friend's house. He can only go into the house to access his well and draw water during the time when people normally enter, during the daytime. He has to leave the house when it's normal for people to leave the house. He can only be around, basically, during normal daytime hours, when it's proper to have other people in your home. He's not allowed to bring his animal in with him to the house and have his animal drink from the well. Rather, he could fill up water from the well and bring it to his animal outside, but he can't bring his animal into the home of this person who has the well under that person's house. It's not respectful. He has access to that well, but he doesn't have the ability to bring an animal into this other person's house.
V'zeh oseh lo potachat (And this one makes a lock for it). V'zeh oseh lo potachat. V'zeh oseh lo potachat. The owner of the well could put a lock on the well or should put a lock on the well, and the owner of the house also puts a lock on the well. The owner of the well puts one because he wants to make sure that when he's not around, the owner of the house is not stealing water from his well. And Hachamim (the Sages) also decreed that the owner of the house could put a lock on the well. The reason for that is to ensure that the owner of the well doesn't show up when the owner of the house is not home and the owner of the well will be in seclusion with the wife. He'll be with the wife of the owner of the house, and it'll lead to bad rumors; it'll lead to suspicion. And therefore, to avoid that, the owner of the well can arrive there and draw water only when the owner of the house is home. But if the owner of the house is not home, there's no access to that well, so there wouldn't be a problem of yichud, of seclusion, between the owner of the well and the wife of the owner of the house.