Yerushalmi Eruvin 1:8 ירושלמי עירובין א׳:ח׳

MISHNAH: If a caravan rested in an area of difficult access¹⁹Which therefore is karmelit, where carrying is forbidden only rabbinically and which therefore can be turned into a kind of private domain by an improvised wall. which they surrounded by the implements of animals²⁰The bags on the beasts of burden may be used as temporary walls for the Sabbath. one may move things inside on condition that the fence be ten hand-breadths high and the openings not be more than the built-up part²¹The bags used for the wall need not touch one another but the openings must be smaller than the lengths of the bags, and no opening may be more than 10 cubits.. Any opening up to ten cubits is permitted since it is like a door; more than that is forbidden.

HALAKHAH: “If a caravan rested in an area of difficult access¹⁹Which therefore is karmelit, where carrying is forbidden only rabbinically and which therefore can be turned into a kind of private domain by an improvised wall.,” etc. Rebbi Aḥa in the name of (Rebbi Ḥasdai) [Rav Ḥisda]²³⁷Since no R. Ḥasdai is otherwise known in the Talmudim, the reading of [G} is preferable to that of the (Leiden ms.).: For whom was this needed? For Rebbi Yose ben Rebbi Jehudah, since Rebbi Yose ben Rebbi Jehudah says²³⁸Mishnah 10., any partition which is not woof and warp is no partition, (the words of Rebbi Yose ben Rebbi Jehuda.)²³⁹This quote from the Mishnah is inappropriate here; it was deleted by the corrector in the ms. But G shows that it belongs to the original text. But he agrees here, and it was stated thus²⁴⁰Babli 15b/16a.: One makes partition with everything, even camel saddles, even tubs, even camels, on condition that between two saddles there not be space for a saddle, between two tubs there not be space for a tub, between two camels there not be space for a camel, and on condition that no standing wall be opposite standing wall and breach opposite breach²⁴¹Not only is it required that the length of the wall be strictly greater than the opening (a matter of dispute in the Babli 15b) but also, and this is accepted in the Babli, that there can be no straight path from an opening on one side to that on the other side. This implies that if the caravan is camping on a road, the roadway has to be blocked at least on one side., but a standing wall opposite a breach and a breach opposite a standing wall.

²⁴⁶This paragraph from Kilaim 4:4 (Notes 82–87,כ), it also is found in Sukkah 1:1 (52a l. 74,ס) The baraita is similar to Tosephta Kilaim 4:6 quoted also in Babli Eruvin 16a. The main difference between Yerushalmi and Babli-Tosephta is that in the latter source, each breach has to be smaller than the surrounding wall whereas in the Yerushalmi only the total length of standing wall has to be larger than the total length of the missing parts.
The problem of kilaim addressed here is that grain must be separated from vines by at least 4 cubits. If the farmer wants to sow grain close to his vineyard, he has to fence off the vineyard by a wall. The question is, what is called a wall? It turns out that concerning kilaim everything less than three [hand-breadths] is considered closed²⁴⁷As noted before, an opening of less than three hand-breadths in a wall is disregarded; in computing the total length of the torn-down parts, breaches smaller than three hand-breadths in width are disregarded.. From three to four, if what is standing is more than what is torn down it is permitted, but if what is torn down is more than what is standing, it is forbidden. From four [hand-breadths] to ten [cubits], if what is standing is more than what is torn down, it is permitted; but if what is torn down is more than what is standing it is permitted where it is standing²⁴⁸The Babli notes that not only are breaches up to three hand-breadths long disregarded as holes, but also standing pieces of wall up to three hand-breadths wide are disregarded as walls. This is the background of the discussion later in this paragraph., forbidden where it is torn down.

Concerning the Sabbath, everything less than three [handbreadths] is considered closed. From three to four, and from four [hand-breadths] to ten [cubits], it is permitted if what is standing is more than what is torn down, but forbidden if what is torn down is more than what is standing. More than ten, it is forbidden even though what is standing is more than what is torn down. Rebbi Ḥananiah, Rebbi Judah bar Pazi, in the name of Rebbi Joḥanan: There is no “from three to four.²⁴⁹R. Joḥanan wants to eliminate the middle part of the baraita, the one dealing with breaches of between three and four hand-breadths, in case that the standing walls also are in pieces less than four hand-breadths wide. While a hole wider than three hand-breadths is considered a breach, a wall narrower than four hand-breadths is not a wall. In that case, there are only holes and no wall at all; the entire wall should be considered as non-existent! He requires in this case that any sown field should be at least four cubits distant from the vineyard.” There is a hole of three and no place of four! Rebbi Mana objected: Did we not state: “One surrounds with sticks,” does a stick form a place²⁵⁰Mishnah 1:10. Since the sticks are counted and no stick is even one hand-breadth wide, any piece of wall should be considered a wall. The answer is that as long as no two sticks are three hand-breadths distant from each other, the entire dividing fence is considered a solid wall.? He said to him, do not object to me from a breach less than three hand-breadths, since anything less than three is considered closed! Rebbi Yose ben Rebbi Abun in the name of Rav: In any case, since what is standing is more than what is torn down, it is permitted²⁵¹This explicitly rejects the text of Babli/Tosephta, that no single hole may be wider than both adjacent pieces of standing wall; the wall is valid as long as the combined length of standing wall (of at least 4 hand-breadths length) is larger than the combined length of the breaches..