1)

(a)When Rava says regarding ...

1. ... water on water 'Haynu Hanachashan", he means - that if someone scoops some water from a collection in his house and carries it out into the street, he is Chayav (because the water was originally considered Munach, in which case his Akirah was valid.

2. ... a nut on water 'La'av Haynu Hanachasan', he means - that it is not considered Munach, in which case, should he pick it up and carry it out, he will not have performed an Akirah, and will therefore be Patur.

(b)He then asks - whether a nut in a vessel, and the vessel is floating on water, is considered Munach (like water on water), or not (like oil floating on water).

(c)The outcome of the She'eilah is - Teiku.

2)

(a)Oil on wine, Rava concludes, is a Machlokes between Rebbi Yochanan ben Nuri and the Rabbanan. When Rebbi Yochanan ben Nuri says in a Mishnah in Tevul-Yom (in connection with Tum'ah) that oil floating on wine is considered one entity - he means that oil is comparable to water on water, and that if the Tevul-Yom touches the oil, the wine because Pasul too.

(b)The Tana Kama holds - that if the Tevul-Yom touches the oil, the wine remains Tahor.

3)

(a)According to Abaye, someone who throws a mat into a pit ten Tefachim deep and exactly eight Tefachim wide is Chayav. If however, he placed a dividing mat into the pit, dividing it into two, he is Patur ...

(b)... because placing the mat detracts from the Shi'ur of four Tefachim (since there will now be two pits each one of less than four Tefachim) and Abaye holds that, when the Hanachah and the nullification of the wall occur simultaneously, one is Patur.

(c)If Abaye renders him Patur here (when one does not tend to nullify the mat) - then he will certainly render him Patur by the She'eilah of Rebbi Yochanan on the previous Amud (where someone places a clod of earth into a pit which is ten by ten Tefachim to begin with, but which now, after he has placed it, is only nine Tefachim), since there, we can assume that he nullified the clod of earth, too.

(d)Rebbi Yochanan, on the other hand, is uncertain even in the case of the clod of earth (where the thrower nullified it), whereas in our case (where the owner does not nullify the mat) he will certainly hold that the Hanachah is not Mevatel the Reshus ha'Yachid, and the thrower will be Chayav.

4)

(a)Someone who throws something into a pit which has the dimensions of a Reshus ha'Yachid, which contains ...

1. ... water - is Chayav, since water does not nullify the walls of a Reshus ha'Yachid.

2. ... fruit - is Patur, because fruit does (see Tosfos DH 'Peiros').

(b)We cite a Beraisa in support of the former ruling. The Tana Kama exempts someone who throws from a main street into the sea or vice-versa - because the sea is a Karmelis.

(c)Rebbi Shimon rules however - that if the place in the sea where he threw from or to which he threw - is four by four Tefachim and ten Tefachim deep, he is Chayav, since that constitutes a Reshus Ha'Yachid ...

(d)... even though it is full of water (a proof that water does not negate the walls of a Reshus ha'Yachid.

5)

(a)Our Mishnah rules that someone who throws four Amos in the street, and the article lands on a wall ...

1. ... above ten Tefachim - is Patur, as if he had thrown through the air above ten Tefachim (which is considered a Makom Petur).

2. ... below ten Tefachim - is Chayav as if he had thrown through the air below ten Tefachim.

(b)In answer to the question how, in the latter case, the article came to rest in the middle of the wall, Rebbi Yochanan establishes the case -side by a sticky fig that stuck to side of the wall.

6)

(a)Rav Yehudah ... Amar Rebbi Chiya cites a Machlokes between Rebbi Meir and the Rabbanan regarding someone who throws something at a wall in the street, and it lands in a small cavity. He is Patur according to the Chachamim. Rebbi Meir rules that he is Chayav - due to the principle of 'Chokekin Lehashlim', which means that wherever there is enough room to carve out four by four Tefachim, we consider as if it has already been carved out.

(b)A Tel ha'Mislaket is a gradient in a street that rises ten Tefachim in the space of four Amos, and which becomes a Reshus ha'Yachid (see Chidushei Maharshal on Rashi DH 'Tel ha'Misleket'), like Rebbi Chanina ben Gamliel learns in the Beraisa that follows.

(c)A Mavoy, says the Beraisa, which has a slope leading up to the Reshus ha'Rabim or down to it, does not require a Lechi (a post which serves as a Mechitzah), by the exit, because the slope already serves that purpose.

7)

(a)Our Mishnah rules in a case where, after someone has thrown an article ...

1. ... less than four Amos, it 'rolls' to a point outside four Amos - that he is Patur.

2. ... more than four Amos, it 'rolls' back to a point inside four Amos - that he is Chayav.

(b)Our Mishnah must be speaking when the object did not actually land, but was stopped by the wind in mid-air and blown one way or the other - because had the Mishnah been speaking about an object which actually landed on the ground, it would be no Chidush to tell us in the Seifa that one is Chayav.

(c)Rebbi Yochanan answers the Kashya 've'Ha Lo Nach' - by establishing the case even where the object actually landed on something.

(d)He might have established the case even where the article did not actually land on something before blowing it back - there where the wind stopped it in its tracks within three Tefachim of the ground.

8)

(a)The Beraisa, which we bring in support of Rebbi Yochanan, rules in the case under discussion, if the object that is caught by the wind ...

1. ... is blown back without stopping - that he is Patur.

2. ... is first stopped in mid-air, before being blown back (presumably within three Tefachim of the ground) - that he is Chayav.

9)

(a)When Rava says that even when the article is within three Tefachim of the ground, it still requires a Hanachah on something, according to the Rabbanan - he is referring to the Rabbanan of Rebbi Akiva, who do not hold of 'Kelutah K'mi she'Hunchah', which Rava now explains, applies even if the object is within three Tefachim of the ground.

(b)Besides exempting the person who throws from one Reshus to another from a Chatas, should the object not actually land in the second Reshus, it also absolves someone who throws from one Reshus to another, and who remembers that it is Shabbos, as the object is falling to the ground - even after it has reached within three Tefachim of the ground. Since he became a Meizid before the object reached the ground, he will be Patur.

(c)Ravina asked Mereimar why Rava is not just duplicating what Rebbi Yochanan said earlier, when he explained our Mishnah in the very same way. To which the latter replied - that when Rebbi Yochanan requires the object to rest on something, he is speaking in a case where it is traveling horizontally; but it does not follow that the same will apply to one which is already falling to the ground. We may well think that there, once it reaches within three Tefachim of the ground, it will not require a Hanachah at all, because there the Rabbanan will agree with the principle of 'Kelutah'. Therefore Rava needs to tell us that even in such a case, the object requires a Hanachah on some sort of surface.

10)

(a)Our Mishnah rules that someone who throws four Amos ...

1. ... in the ocean - is Patur.

2. ... four Amos along a pool that runs along a Reshus ha'Rabim - is Chayav provided the pool is less than ten Tefachim deep, but not if it is more.

(b)The Tana finally rules that someone who throws four Amos in a pool of water that runs along a Reshus ha'Rabim' - is Chayav.

11)

(a)We already discussed this Mishnah in the first Perek. The Tana repeats ...

1. ... 'Hiluch' ('u'Reshus ha'Rabim Mehaleches Bo') to teach us - that one is only Chayav in a Reshus ha'Rabim along which it is easy to walk.

2. ... Rekek Mayim - to teach us that it applies both in the summer (when people will walk along it to cool themselves down) and in the winter (when they do not care to walk along it because the roads are wet and muddy anyway).

(b)Abaye, in our Sugya, explains that the Mishnah repeats 'Rekek Mayim', to teach us that this Din applies even to a pool which is more than four Amos long - where we might otherwise have thought that people would prefer to make a detour to avoid walking along it.

(c)And when Rav Ashi answers that it is to extend the Din of Reshus ha'Rabim even by one that is less than four Tefachim wide, he means - that we might otherwise have precluded it, since people tend to jump over such a small stretch of water rather than wading through it.

(d)And his ruling here follows his ruling - declaring Chayav someone who throws something on to a plank of a bridge that is slightly apart from the other planks, because even though a lot of people will avoid stepping on it, there are many that do.

12)

(a)One is Patur for throwing from the sea on to dry land or on to a ship, or vice-versa, or from one ship to another - because one is not Chayav for throwing to or from a Karmelis, whether it is to or from a Reshus ha'Yachid, a Reshus ha'Rabim or another Karmelis.

(b)The Mishnah which prohibits carrying from ship to another, even when they are next to each other - is speaking about two ships belonging to two people who made an Eruv. However the Eruv, which permits them to carry from one ship to the other, is effective only as long as the two ships are tied together, and our Mishnah speaks when they became untied, even though they are still next to one another.

(c)Rav Huna permits drawing water by means of a Ziz - a ledge, which serves no purpose than a Heker (to remember not to carry from a Karmelis directly), but not to permit anything which would otherwise be Asur (in this case).

13)

(a)The reason that Rav Huna is so lenient in this regard is - because he measures the ten Tefachim height of a Karmelis from the sea or river-bed. Consequently, the space from the surface of the water until the top of the ship's hull has the Din of a Makom Petur, and it is permitted to carry from a Karmelis to a Reshus ha'Yachid (or Rabim) via a Makom Petur (since Chazal's decree to carry from one Reshus to another via a Makom Petur, is restricted to Reshuyos de'Rabbanan).

(b)According to Rav Chisda and Rabah bar Rav Huna, a Mechitzah Teluyah is required - comprising three walls plus the wall of the ship, with a hole of four Tefachim in the middle.

(c)Rav Chisda and Rabah bar Rav Huna are more stringent than Rav Huna - because they reckon the ten Tefachim of the Karmelis, not from the sea or river-bed, but from the top of the water. Consequently, the space between the sea and the top of the hull of the ship (which is less than ten Tefachim) has the Din of a Karmelis. Therefore, they require a proper Heter, since one is carrying from a Karmelis to a Reshus ha'Yachid (which is Asur mi'de'Rabbanan.

14)

(a)A Sefinah is a ship - whereas an Arivah is a small boat (such as a rowing-boat).

(b)Rav Nachman asked Rabah bar Rav Huna why Rav Huna does not suspect that sometimes the ship travels in low water, so by putting out no more than a Ziz, he will be carrying from a Karmelis to a Reshus ha'Yachid. Rabah bar Rav Huna replied - by referring to the assumption that a ship (as opposed to a boat) cannot travel in water that is less than ten Tefachim deep.

(c)Rav Huna is not worried that one might draw water from the front of the ship, which is above the water, even when the water is less than ten Tefachim deep, before the hull of the ship reaches that point, says Rav Safra - because they tended to have men standing there with poles, to test the depth of the water just before the ship reached that point, and if the water became too shallow, they would immediately steer the ship clear of that point.

15)

(a)Rav Nachman bar Yitzchak asked Rebbi Chiya bar Avin, how, according to Rav Chisda and Rabah bar Rav Huna, they got rid of their dishwater. The latter replied that, according to Rav Chisda and Rabba bar Rav Huna maintain - they would throw their dishwater on to the side of the ship, form where it would run down into the sea.

(b)There is no Isur of Kocho (when something flows down a slope, after one placed it there) - because Chazal did not decree Kocho by a Karmelis.

(c)They could have poured it out via the Mechitzah Teluyah - only it rather unappetizing to use the same outlet to get rid of one's dishwater as the one that one uses to bring in one's drinking water.

16)

(a)The Tana Kama of a Beraisa - forbids carrying from a ship to the sea, or vice-versa.

(b)Rebbi Yehudah refers to a ship that is ten Tefachim deep - from its deck to its base, but less than ten Tefachim high - from the sea to the deck.

(c)He permits carrying from the ship to the sea, but not vice-versa - because it is forbidden to carry from a Karmelis to a Reshus ha'Yachid.

(d)Yet he permits carrying from the ship to the sea - by pouring whatever it is on to the side of the ship and letting it run down into the sea ...

(e)... a proof that 'Kocho be'Karmelis Lo Gazru'.