We learned in our Mishnah that a gutter is subject to Chazakah. The problem with this, according to Rebbi Yirmiyah bar Aba (who explains that 'Marzev Ein lo Chazakah' refers to building underneath it) is that seeing as his gutter runs along the length of the Chatzer, what difference does it make to him if the owner of the Chatzer builds underneath it?

There is no problem according to Shmuel and Rebbi Chanina' interpretation of 'Marzev Ein lo Chazakah' - according to whom the Tana needs to inform us that one cannot force him to move his drain-pipe to the other side, or that the owner of the Chatzer is not entitled to cut the pipe shorter.

We answer that the Tana is talking about a gutter that is built in the form of a building - in which case he can complain that whenever the owner of the Chatzer underneath it bangs with metal implements, it weakens his gutter, causing it to collapse.

Perhaps a plain Marzev is different because it is not sufficiently important to prevent the owner from building underneath it, even if it will cause it to fall down. Alternatively, we might explain the difference between a Marzev and a Mazchilah in that a Marzev is normally made of wood, and will not be adversely affected by the building underneath it, whereas a Mazchilah is made of stone.

Rav Yehudah Amar Shmuel rules that if Reuven wants to dismantle a pipe from which water flows from his roof into Shimon's Chatzer, Shimon is entitled to object ...

... because he has as much of a Chazakah on Reuven's water, as Shimon has in his Chatzer.

They asked the same She'eilah to Rebbi Oshaya, to Rebbi Chama and then to Rebbi Biysa. Rebbi Oshaya and Rebbi Biysa corroborated Rav Yehudah Amar Shmuel's ruling ...

... whereas Rebbi Chama ruled that the owner of the Chatzer has no authority to stop the owner of the pipe from dismantling it.

Rami bar Chama quoted the Pasuk "ve'ha'Chut he'Meshulash Lo bi'Meheirah Yinasek" - with reference to Rebbi Oshaya, whose father was Rebbi Chama, and whose grandfather (with whose opinion he sided) was Rebbi Biysa.

According to de'Bei Rebbi Yanai - a Sulam ha'Mitzri has a maximum of four rungs.

The Tana defines an Egyptian window, but not an Egyptian ladder - because Rebbi Yehudah argues with the Tana Kama regarding the former.

Rebbi Zeira restricts the Chazakah on a Chalon Tzuri (in our Mishnah) to one that is within four Amos from the ground - because, due to the combination of the size of the window, and the height (which enables him to look into his neighbor's garden, we can be quite sure that if the neighbor had not granted him permission to build the window, he would certainly have objected.

If, on the other hand, he now wants to build such a window - the neighbor is entitled to object.

If the window is above four Amos - then he neither has a Chazakah nor can his neighbor object.

When Rebbi Zeira adds 've'Eino Yachol Lim'chos' he means that - it is because the neighbor cannot stop him from building the window, that he does not have a Chazakah (Rabeinu Gershom).

According to Rebbi Ila'a - he does not have a Chazakah, and his neighbor is allowed to protest and force him to close the window above four Amos whenever he wants.

We suggest that they are arguing over 'Kofin Oso al Midas S'dom', in which case - Rebbi Zeira will hold 'Kofin' (meaning that we force the owner to accept the window, since it does not cause him any loss), whilst Rebbi Ila'a holds 'Ein Kofin (and if he wants to protest, he may).

We conclude however, that both opinions hold 'Kofin al Midas S'dom', and on principle, Rebbi Ila'a would agree with Rebbi Zeira. And the reason that he argues here is because the owner has a genuine fear that the Machzik will place a stool on his side of the wall in order to watch him through the window.

Rebbi Zeira disagrees with this however - because a person would not have such Chutzpah.

A case came before Rebbi Ami of someone who wanted to open such a window above the height of four Amos from the ground. Rebbi Aba (to whom Rebbi Ami sent them) ruled - like Rebbi Ila'a (upholding the owner's protest).

We have already discussed Shmuel's opinion (though not by name) that if the window is to provide light, then even a Chalon ha'Mitzris is subject to a Chazakah - because light is something that one needs all the time, and which is therefore considered a permanent fixture.

A 'Ziz' is a ledge.

The distinction the Mishnah makes between a Ziz which is at least a Tefach wide and one which is less, with regard to ...

... a Chazakah is that - the former is subject to Chazakah, whereas the latter is not.

... Mecha'ah is that - in the former case, the owner of the Chatzer can object, whereas in the latter, he cannot.

The sort of damage we are concerned with in the case of a Ziz that is a Tefach wide is Hezek Re'iyah (that he will stand on the ledge and look into the Chatzer).

Abaye interprets Rebbi Asi (or Rebbi Ya'akov) Amar Rebbi Mani's statement 'Hichzik be'Tefach, Hichzik be'Arba'ah' to mean that if Reuven has a Chazakah on a ledge one Tefach wide along a length of wall that is four Tefachim, this automatically extends to a ledge which is four Tefachim wide ...

If the Machzik made a Chazakah on a Ziz one Tefach wide by ...

... ten Tefachim along the wall - his Chazakah also extends to one which is four Tefachim wide.

... three Tefachim along the wall that is what he is allowed (three Tefachim by one), and no more.

We learned in our Mishnah that 'Pachos mi'Tefach, Eino Yachol Lim'chos'. Rav Huna confines this prohibition to the owner of the ledge. This might mean that the Machzik cannot stop the owner of the Chatzer from building ledges on his wall. Alternatively, it means that - he cannot stop him from using his ledge (seeing as he has the authority to remove it, if he so wishes).

According to Rav Huna, the owner can however, stop the Machzik from fixing the ledge on his wall - because he is afraid that he will use it to look into his Chatzer.

Rav Yehudah that 'Eino Yachol Lim'chos cuts both ways (not because he holds 'Hezek Re'iyah Lo Sh'meih Hezek', but) - because the Machzik can counter that, since the ledge is only fit to use to place things on, whenever he uses the ledge, he promises to turn his face the other way (Consequently, he will be afraid to look into the Chatzer, so as not to be caught in the act).

Rav Huna counters this by pointing out that - due to the thinness of the ledge and the precariousness of using it as he bends over from the roof, he can always claim that he turned round to face the Chatzer in order to avoid falling off the roof (even when it is not true).

Our Mishnah - prohibits opening a new window overlooking the public Chatzer of which one is a joint owner (because of Hezek Re'iyah).

And if he purchased a room in an adjoining Chatzer or if he built an attic above his house, he is forbidden to build a door that opens from it directly into the Chatzer which he still owns jointly - because he causes an (un-wanted) influx of visitors to pass through the Chatzer.

The Tana permits this however if he builds one room next to the other or an attic on top of his house, provided his guests enter the Chatzer via his house, and not directly - because, in this way, the influx is confined to his house rather than to the Chatzer, and one is not restricted as to how many guests one invites into one's home.

The problem with our Mishnah teaching us the prohibition of opening a new window overlooking the public Chatzer which he owns jointly is - the implication that it is permitted if the Chatzer is privately-owned, which is not the case.

We answer that the Chidush is greater in the case of a public Chatzer than of a private one - since each person has to be on his guard because of the other residents anyway, so we may have thought that opening another window makes no difference (and is not considered 'Hezek Re'iyah').

It is nevertheless forbidden a. because they can argue that whereas until now, they only had to guard thyemselves when they were in the Chatzer, now they need to guard themselves when they are in the house too (since from his high window, he can now look into their houses - b. because they can claim that from now on, they need to guard themselves even when he is in the house (whereas previously, this was it was confined to when he was in the Chatzer).

When a resident opened windows on to the Chatzer, Rebbi Yishmael b'Rebbi Yossi declared that he had a Chazakah - because he held that silence concerning Hishtamshus (usage) creates an immediate Chazakah.

Rebbi Chiya - instructed the Machzik that, just as he took the trouble to open the window, so he should now take the trouble to seal it ...

... because, in his opinion - this Chazakah too, only takes effect after three years (and in this case, the owner did protest within three years).

Rav Nachman rules that if, after three years, Shimon sealed the window that Reuven opened, and Reuven remains silent, Reuven's Chazakah is broken - because, had Shimon granted him the right to open the window, he would have protested immediately when he sealed it.

The problem with our Mishnah, which permits building one room next to the other or an attic on top of his house (despite the fact that his guests enter the Chatzer via his house, and not directly) is that - when all's said and done, it is the extra building that brings the additional visitors into the Chatzer, so how can the Tana permit it?

To resolve the problem, Rav Huna explains the extra room and the attic to mean that - it speaks where he divided the existing room into two, either vertically or horizontally (thereby adding nothing to the existing building.

This alleviates the problem - inasmuch as a person can entertain as many guests as he likes in his existing house, no matter how he does it.