REGULATIONS CONCERNING THE COMBINING OF ROOFS ON SABBATH.
MISHNA: All the roofs of a town are considered one private ground (although the houses underneath are occupied by several), provided there be not one roof ten hands higher or ten hands lower than the rest. Such is the dictum of R. Meir; the sages, however, hold, that each roof constitutes a separate private, ground. R. Simeon said: Roofs, as well as courts and wood-stores, constitute one private ground, for the carrying of all such utensils as were actually situated there when the Sabbath set in, but not for the carrying of such utensils as were still in the house, when the Sabbath set in.
GEMARA: Abayi bar Abhin and R. Hanina bar Abhin were sitting alongside of Abayi, and were conversing between themselves: “It is right according to the sages, who hold, that, in the same manner as the houses are separated below, so are also the roofs above; thus, unless an Erub is made between the houses, it is not permitted to carry from one roof to the other; but what is the opinion of R. Meir? Does he hold, that as the houses are separated so are also the roofs, why does he state, that all the roofs constitute one private ground; or if he holds that above ten spans there is nothing but private ground, what difference does it make to him, whether a roof be ten spans higher or lower than the rest?” Said Abayi to the two brothers: “Have ye not heard the dictum of R. Itz’hak bar Abhdimi to the effect, that R. Meir said thus: ‘Where there are two distinct premises both of which, however, are legally private ground, e.g., a pillar, ten spans high and four spans wide standing in private ground, and which must not be used to shoulder burdens thereon on the Sabbath, lest a heap of the same size standing in public ground be used for the same purpose,’ so it is also in this case, where a roof is ten spans lower or higher than the rest the same precautionary measure applies.”
The two brothers hearing this from Abayi thought, that according to R. Meir the same case applied to a mortar or kettle,
ten spans high; said Abayi to them: “My master told me, that R. Meir said, this precaution applied only to a pillar and a millstone because for these two objects special places are designated, but as for other utensils, even if they be ten spans high, the precaution is unnecessary.”
“The sages, however, hold, that each roof constitutes a separate private ground.” It was taught: Rabh said: “On every roof things must not be handled except within a limit of four ells,” but Samuel said: “They may be handled in the whole extent of the roof.” If the roofs are separated and the separation is apparent, all agree, that carrying things on those roofs is permissible (because in this case the walls underneath are considered as if they reached up to the tops of the
roofs) but they differ concerning roofs that are separated, where the separation is not apparent. Rabh holds that things must not be carried on those roofs (where the separation is not apparent) except for a distance of four ells, because he does not admit, in this case, the theory of Gud Assik (possibility of the walls reaching up to the tops of the roofs), while Samuel, who does admit the theory, holds, that carrying is permitted in the entire extent of the roofs (because he admits of the possibility of the walls reaching the tops of the roofs).
An objection was made based upon our Mishna: The sages hold, that each roof constitutes a separate private ground. This is in accordance with Samuel’s opinion but is contradictory to the opinion of Rabh. The disciples of Rabh said in his name, that the statement, “things must not be handled except within a limit of four ells,” meant to signify, “two ells in each adjoining
roof” (but in the one roof things may be handled throughout its entire extent).
Abayi said: “If a man erected an attic on top of his house and provided it with a small door four spans wide, he may carry things in all the roofs.” (The reason for this statement is, that the fact of the man having made an attic and provided it with a door is proof, that the other inmates had resigned their right to the use of the roof in his favor.) Said Rabha: “It may happen, that the small door with which the attic was provided may prevent the man from using the other
roofs” (even according to R. Meir). How so? If the door in the attic faced a garden below and the partition made by the attic separated his roof from the others, it might be said, that he made that door merely so as to be able to watch his garden and renounced his right to the use of the roofs.
(It was taught:) Roofs, level one to the other in which, according to R. Meir, it is permitted to carry things, and a single roof which may be used according to the sages, may according to Rabh be used throughout their whole extent, while according to Samuel, it is only allowed to use them for an extent of four ells. Would not this be a contradiction by Rabh to his previous statement and by Samuel to his own former dictum? This can be explained thus: Rabh’s previous statement referred to a case, where the separation between the roofs was not apparent while in this case the separation is apparent and Samuel’s former dictum referred to a roof that had less than two saahs’ capacity, while in this case it refers to a roof that has a capacity of more than two saah. Why should a roof of that size not be allowed to be used? The possibility of the walls reaching the tops of the roofs is not admitted, for the reason that partitions which enclose dwellings are made downwards and are not supposed to extend upwards, and of a space which is not enclosed by partitions of dwellings and has a capacity of over two saah, only four ells may be used.
It was taught: Concerning a ship, Rabh said, one may carry things throughout the whole extent of the ship, because the space of a ship is enclosed with partitions, and Samuel said, one may carry only to the extent of four ells. Why so? Because the partitions were not made for the purpose of making the space inhabitable but merely to keep out the water. Said R. Hyya bar Joseph to Samuel: “According to whose opinion does the Halakha prevail? According to thy opinion or according to Rabh’s,” and Samuel answered, “The Halakha prevails according to Rabh.”
R. Giddel in the name of R. Hyya bar Joseph said: “Rabh agrees with Samuel’s opinion, concerning a ship that was in dry dock and turned over, that it was only permitted to carry things
for a distance of four ells.” For what purpose was the ship turned over? If people lived within it, why should it not be allowed to carry things throughout its whole extent? Is the bottom of the ship not equal to a roof, when the ship was turned over? Nay; the ship was turned over for a coating of tar.
R. Jehudah said: When we shall arrive at the final conclusions of R. Meir we shall find that all roofs are considered as one private ground in their own right, i.e., that carrying from one roof to the other is permissible; also that all courts are considered as one private ground and likewise all woodsheds, but
from the final conclusions of the sages we shall learn, that roofs and courts constitute one private ground, i.e., that it is permitted to carry things from the roof to the court and vice versa, which, according to R. Meir is not allowed. The woodsheds, however, are considered according to the sages a separate private ground, i.e., things may be carried from one woodshed to another but not from a woodshed into a court. The final conclusions of R. Simeon denote, that all roofs, courts, and woodsheds are considered as one private ground.
We have learned one Boraitha in support of Rabh and another in support of R. Jehudah. The one supporting Rabh reads as follows: “All roofs of the town are considered as one private ground; but it is prohibited to carry things from the roofs to the courts, and vice versa.” Vessels which were situated in the court before the Sabbath set in, may be carried in all the courts, and those situated in the roofs before the Sabbath set in may be handled in all the roofs, provided there is not a roof ten spans higher or lower than the rest. Such is the dictum of R. Meir; but the sages said: Every roof constitutes a separate ground and things must not be carried in it for a distance of over four ells. This bears out the statement of Rabh in which he says that when the separation between the roofs is not apparent one must not carry except in a limit of four ells.
In support of R. Jehudah we have learned the following Boraitha: Rabbi said: “When we learned the Law at R. Simeon’s in the city of Thequa, we would carry towels and oil from one roof to another, from that to the court, and from that to another, and from the other court to a woodshed, and from that to another, until we would come to the springs where we would bathe.”
Said R. Jehudah: “It happened in a time of danger, that we brought up the sacred scrolls from a court to a roof, from the roof to another court, and from that to a woodshed in order to read therein.” The sages answered: “Acts committed during a time of danger do not serve as evidence.”
“R. Simeon said: ‘Roofs as well as courts and woodsheds,'” etc. Said Rabh: “The Halakha prevails according to R. Simeon, providing no Erub was made, but if an Erub was effected, it is not so, because there is fear, lest the utensils from the houses be carried out on the Sabbath and are then carried about in all the courts.” (R. Simeon himself admits, that they form one private ground for the carrying of such utensils as were actually
within the courts or roofs when the Sabbath set in but nor for such utensils as were within the
house.) Samuel, however, as well as R. Johanan, said: “There is no difference whether an Erub was made or not.”
R. Hisda opposed this: According to Samuel and R. Johanan there will be two kinds of vessels in the court, one kind, which had already been situated in the court when the Sabbath set in, and the other, which was brought out from the house during; Sabbath. Is then not the precautionary measure decreed by Rabh really necessary? Simeon holds to his theory that precautionary measures are not necessary.
Come and hear: “Five courts which opened into each other. and also opened into one alley, the inmates of which had all forgotten and not combined an Erub, (the inmates) are prohibited to carry in or carry out from the court into the alley, or from the, alley into the court. The utensils which were situated in the courts when the Sabbath set in may be carried in the courts, but the utensils which were situated in the alley must not be carried even in the alley. R. Simeon, however, permits this to be done (even to carry the utensils of the court into the alley) because he used to say: as long as many people lived there and had forgotten to combine an Erub, the roof, the court, the balcony, the gallery, the woodshed, and the alley are all considered the same legal premises.” Thus we see that R. Simeon makes this decree only if no Erub was made, but if an Erub was made he would not do so; hence he contradicts Samuel and R. Johanan? Nay; R. Simeon states this merely to supplement the statement of the sages and says to them: “As far as I am concerned it makes no difference whether an Erub was made or not, but according to your opinion, grant me, that when no Erub was made the courts, the roofs, etc. all constitute the same legal premises.” The sages, however, answered: “Nay; according to our opinion, each constitutes separate premises.”
Said Rabhina to R. Ashi: “Is it possible that R. Johanan said this? Did not R. Johanan say, that the Halakha prevails according to an anonymous Mishna, and we have learned previously (Chapter VII., Mishna 2) concerning a wall between two courts, if there was fruit on the wall, the inmates of both courts may partake of the fruit providing they do not carry any of it down with them? Hence we see that it is not permitted, according to that Mishna, to carry things from one court into another even if an Erub was made by each court!” (R. Ashi answered:)
By carrying it down is meant carrying it down into the houses, but carrying it down into the courts is permitted.
Asked Rabhina again: “Did not R. Hyya teach (in addition to the quoted Mishna), ‘providing the inmates of each court do riot take it down into their respective courts and eat it’?” Said R. Ashi: “If Rabbi did not teach this in the Mishna, whence does R. Hyya adduce that explanation (I think that my interpretation of the Mishna is correct)?”
It was taught: “If there were two courts, which had a ruin between them and the inmates of one court combined an Erub, while the inmates of the other did not, R. Huna said that the court that had not the Erub is entitled to the ruin (i.e., the vessels situated in their court may be transferred to the ruin) but the court that had combined the Erub is not entitled to the ruin for fear that they might carry out vessels, which were situated in their houses on the Sabbath, into the court, and thence into the ruin.”
Hyya, the son of Rabh, however, said: (I heard from my father) that even the court that had an Erub combined may be entitled to the ruin and I explain my father’s dictum to signify, that the utensils contained in either court may be transferred to the ruin. If thou shouldst explain my father’s dictum to signify, that neither of the courts may make use of the ruin, because he understood R. Simeon’s decree to mean “if they had made an Erub they became separate premises,” hence, in this case, one of the courts having combined an Erub interferes with others also, I will answer it by saying, that such would be the case if there were an occupied court between them, in which event there might be vessels which were situated in the court when the Sabbath set in and also vessels which had been carried out of the houses, so that it would be impossible to distinguish which could and which could not be carried throughout all the courts. When, however, as is the case here, a ruin is between the two courts where there are no vessels which are actually situated there, the danger of confusion is removed and hence my explanation is, that it is permitted for both courts to transfer their vessels to the ruin.
MISHNA: If a large roof adjoin a small one, the owners of the large roof are permitted to carry things thither from the house, but the owners of the small roof are prohibited to do this. If a large court opens into a small one, through a breach in the wall, the inmates of the large court are permitted to carry things through the breach, but the inmates of the small court
are prohibited to do so, because the smaller court is considered as an entry to the larger.
GEMARA: Why does the Mishna teach both cases, concerning a roof and a court? According to Rabh, the object is to demonstrate that in the same manner as courts are divided by partitions so should the partitions between roofs be apparent. According to Samuel, the object is to show, that a roof is on a par with a court, i.e., as the latter is used by many, so also is the former.
Rabba, R. Zera, and Rabba bar R. Hanan were sitting together and Abayi sate close by. They said: “From this Mishna we may adduce, that the inmates of the larger court control the actions of the smaller, whereas the inmates of the smaller court exert no influence over those of the larger. How so? (For instance:) If vines were planted in the larger, other seed must not be planted in the smaller; but if the vines were planted in the smaller, any other seed may be planted in the larger. If a woman who was to be divorced stood in the smaller court and the bill of divorce was thrown to her from the larger court, she is thereby legally divorced, but if she stood in the larger and the bill was thrown to her from the smaller court, she is not legally divorced. If the congregation assembled for prayer stood in the larger and the reader who was to recite the prayer for them was in the smaller, they have acquitted themselves of their duty; if they were in the smaller court, however, and the reader was in the larger, they have not. If there were nine men in the larger court and one man in the smaller, that one man is counted in with the nine and it constitutes a legal assembly for prayer or for the commission of religious acts, but if there were nine men in the smaller and one in the larger that one man cannot be counted in. If there was a filthy thing in the smaller court (on account of which the Shema prayer could not be recited) the larger court may nevertheless recite the prayer; but if the filthy thing was in the larger court the inmates of the smaller are not allowed to do so.”
Said Abayi to them: “According to this then, a partition, which under ordinary circumstances should facilitate the observance of laws, would prove a detriment; for were there no partition
between the larger and smaller court and vines were planted anywhere within the two courts, a man would simply be obliged to measure off four ells whence the vines grew and could then plant whatever he chose.”
Rabha, through R. Shmaiah ben Zera, sent the following query to Abayi: “Do we not find as a matter of fact that a partition at times proves a detriment? Did we not learn in a Boraitha, that concerning the partitions of a vineyard there are instances where they make the observance of laws more lenient and on the other hand there are instances where they make it more rigorous.” How so? If the vines are planted hard by the partition, one may on the other side of the partition plant whatever he chooses. If there were no partition, however, he would have to measure off four ells whence the vines grew and then plant whatever he chose. This is an instance of leniency caused by the partition. When does it make the law more rigorous? If the vines were planted to within eleven ells of the partition, it is not allowed to plant other seed anywhere within those eleven ells; but if there were no partition, four ells would suffice between the vineyard and the place where other seed was to be planted. Rejoined Abayi: “Why base thy query upon a Boraitha, if in thy opinion the partition is the main issue? Why not cite the following Mishna? (Kilaim, Chapter IV., Mishna 2:) ‘If the space between the vineyard and the fence which surrounds it be less than twelve square ells, no other seed may be sown therein; but if it measure that superficies, a vacant space must be allowed for the cultivation of the vines growing near it, and the rest of the ground may be used for saving (other seed).'” We must say, that because in the Mishna the partition is not the issue, but it is a question of the space between the four ells allowed for the cultivation of the vineyard and the four ells allowed to the hedge or fence, and if such space is four ells wide (i.e., if the whole is twelve) other seed may be sown therein, but if less than four, it is abandoned. Hence we might say, that the same issue is treated of in the Boraitha?
illustration A illustration B
R. Jehudah said: “If there are three woodsheds opening into each other, of which the two outer are enclosed while the middle one is not (see illustration A), and there is a man in each of the wood sheds, the men are considered as a caravan and are entitled to as much room as they desire. If the middle one, however, was enclosed, but the two outer ones were not (see illustration B), and there was a man in each of the three woodsheds, they are entitled to a space of six
saahs’ capacity, i.e., two saahs to each man. (For the reason, that in the first instance the middle woodshed is smaller than either of the two outer ones and is virtually absorbed by them, while in the latter case, the middle woodshed is the larger, but cannot absorb the two outer ones, hence the men cannot be considered as a caravan.)”
The schoolmen propounded a question: “How is it if (in the latter instance of the woodsheds, illustration B) there were two men in the middle woodshed and one each in the outer sheds? Shall we assume that the two men of the middle shed, having a right to either shed, are considered as being in either one of the two outer sheds, and three persons being in one place, thereby form a caravan, or shall we say, that as there are two men in the middle woodshed, each one of them can occupy either court, in which event there would be two people each in the outer courts and no caravan is formed–consequently they are entitled only to a space of two saahs’ capacity for each man? If the latter instance should apply, how would it be if there were two men in each of the outer sheds and one man in the middle shed? Whichever court he might occupy, there would be three men, and thus a caravan would be formed, or, because there is doubt which he would occupy, having a right to either, it would not be considered as a caravan?” The answer was: “All ordinances pertaining to Erubin should be construed in their most lenient form.”
Said R. Hisda: “If a court was five spans higher at the edges than in the centre and a partition of five spans height was added to the edges, it does not constitute a valid partition; for either the edges must be ten spans high to commence with or the partition must be made ten spans high.” Mareimar, however, maintained, that the two may be counted together and constitute a legal partition.
Rabhina met R. A’ha the son of Rabha and asked him: “Does the master teach anything pertaining to partitions?” and he answered: “Nay.” The Halakha prevails, that the edges of the court and the partitions are counted together and constitute a legal partition.
R. Oshiya propounded a question: “How is it if new habitations are added to a court on the Sabbath (i.e., if a wall between two courts had become broken and thus new dwellings were added); do they impede the inmates of that court or not?” Said R. Hisda: Come and hear: (We have learned this in our
Mishna:) “If a large court opens into a small one, through a breach in the wall, the inmates of the large court are permitted to carry things through the breach, but the inmates of the small court are prohibited to do so.” Rejoined Rabba: “Perhaps the Mishna refers to a breach that was made before the Sabbath set in.” Said Abayi: “The Master should not say ‘perhaps’; it is certain, that the breach was caused on the eve of Sabbath; because didst not thou, Master, say thyself at one time, that thou didst ask of R. Huna and of R. Jehudah concerning an Erub which was made through an aperture or a door which had accidentally become closed up on the Sabbath and they told thee, that if that happened after the Sabbath set in, the Erub is valid for the whole Sabbath, having been valid at the beginning (and they certainly would not contradict a Mishna)!”
It was taught: If a wall between two courts was destroyed on the Sabbath, Rabh said, that it is not permitted to carry things in either of the courts for a distance of over four ells, but Samuel maintains, that the inmates of each court may carry as far as the ruins of the wall. The statement herein attributed to Rabh was not made by him outright, but was inferred from the occurrence as follows. Rabh and Samuel were both sitting in one court on Sabbath and suddenly the wall of the court caved in. Said Samuel to the other inmates of the court: “Take a garment and hang it up in place of the wall.” Rabh turned away his face from Samuel. Said Samuel: “If Abba (Rabh) is angry let him take his girdle and fasten the garment with it to the wall.” If according to Samuel it is allowed to carry as far as the ruins of the wall, why did he order that a garment should be fastened as a partition? Samuel did not order this to be done in order to make a partition but merely to prevent outsiders from peering into the court. And Rabh! if he holds that it is not allowed to carry he should have said so? It was Samuel’s domain, and he could not contradict him at that time. Why then did he turn away his face? (Surely he is not responsible for Samuel’s actions.) In order to show that he did not agree with Samuel’s opinion but still adhered to his own.
MISHNA: If a court (through an incavation of its walls) is laid open to public ground, whosoever brings anything from private ground into such a court, or from the court into private ground, is culpable. Such is the dictum of R. Eliezer, The sages hold, however: Whoever brings anything from the court into public ground, or from public ground into the court. is
absolved; since the court (through the incavation of its walls and consequent opening) has become like unclaimed ground.
GEMARA: Does R. Eliezer hold, that if a court by reason of the incavation of its walls is laid open to public ground, it becomes public ground? Yea! He holds to his theory as expressed elsewhere (Baba Bathra), that if the public had taken a certain path through a meadow (although there was no path) and used it constantly, it remains a path (and the same is the case with this court; if it was laid open into public ground it becomes the same as public ground). This is not so! Did not R. Giddel say in the name of Rabh, that R. Eliezer (in the passage quoted) referred to a case where the original path had been lost and could not be found, and if we would assume that in the case of the court he holds, that only the space which had been lost to the public, i.e., where it is not apparent that the wall had been standing, becomes as public ground, but the whole court is certainly not to be considered such; did not R. Hanina say, that the sages and R. Eliezer differ as to the entire space up to where the wall was standing? Hence we must say, that
R. Eliezer holds the entire court to have become as public ground! The statement of R. Hanina should be modified to the effect, that they differ only as to the space that had been occupied by the wall and not up to the wall; thus R. Eliezer does not consider the entire court as public ground. If you wish, I may say, that (the place where the wall stood is still apparent, and) the sages differ with R. Eliezer merely as to the adjoining places to public ground. R. Eliezer holds them to be the same as public ground, while the sages say that, as there had at one time been a court there, it is now not public ground.
MISHNA: In a court (the corner walls of which had fallen in on Sabbath so) that (it) has been laid open to public ground on two sides; also in a house (which by a similar accident) was laid open on two sides; or in an entry the cross and side beam of which had been removed, it is permitted to carry things on that same Sabbath; but it is not permitted to do so on the succeeding Sabbaths. Such is the dictum of R. Jehudah; but R. Jose said: If it were permitted for that particular Sabbath, it would also be permitted for the future; but since it is prohibited for the future, it is also prohibited on that same Sabbath.
GEMARA: How is the case with the-walls treated of in the Mishna? If the breach caused by the incavation does not exceed ten ells, (it is regarded as a door) so what difference does
it make upon how many sides the court has been laid open? If the breach, however, exceeded ten ells, then it would be the same even if one side only were laid open. Said Rabh: The breach does not exceed ten ells but in a corner it is not customary to make a door.
“A house which was laid open on both sides,” etc. How would it be if the house were laid open only on one side? We would say, that the edge of the roof is supposed to reach down to the bottom and thus serve as a substitute for the wall by application of the law of “Gud Achith.” Cannot the same rule apply to two sides of a house? Let the edge of the roof on both sides be supposed to reach down to the bottom? Said the disciples of Rabh in the name of their master: “The Mishna refers to a house where the corner walls had fallen in and where the roof was not flat but slanting, so that with the walls it also fell.”
Samuel said: “In the case of a court the Mishna does refer to an instance where the breach exceeded ten ells, but it also states that the walls had caved in on both sides because further, when treating of a house, it must specify two sides, hence it does so also when courts are in question.” Why must two sides be mentioned in the instance of a house? Cannot the edge of the roof be supposed to reach down to the bottom of both walls? Then again does Samuel hold to the supposition, that the edge of the roof reaches to the bottom of the wall? Was it not taught that concerning a gallery in a valley, Rabh said, it is permitted to carry throughout the whole extent of the valley, because the edges of the gallery are supposed to reach down to the ground and thus form a partition for the entire valley, whereas Samuel maintained that this supposition cannot be considered and hence it is only permitted to carry for a distance of four ells? This would not present a difficulty, for in that case Samuel maintains, that the edges of the gallery must not be supposed to reach down to the ground because there must be four distinct partitions, but where only three are necessary he would admit the feasibility of such a supposition. The difficulty concerning the two sides of the house where the breach measured over ten ells still remains! In the same manner as the disciples of Rabh referred to a house where the corner walls had fallen in together with their slanting roof, Samuel may refer to a house, the corner walls of which had sustained a breach four ells in width on each corner, or eight ells in all, and five ells in length
on one side, and five ells and a trifle on the other side, or slightly over ten ells in all. Hence it would be necessary to suppose that the edges of the roof reach down on four sides of the breach two in width and two in length and that would be contrary to the theory of Samuel!
Why does Samuel not hold with Rabh? Because the Mishna does not mention a slanting roof and Rabh does not hold with Samuel because he (Rabh, as we have seen in the instance of the gallery in the valley) permits of the supposition, that the edges of a gallery or a roof can reach down on four sides.
“R. Jose said: If it were permitted for that particular Sabbath,” etc. The schoolmen propounded a question: “How is R. Jose’s dictum to be construed? Does he mean to permit it entirely or to prohibit it entirely?” R. Shesheth as well as R. Johanan said: “He means to prohibit it entirely.” We also learned to this effect in a Boraitha, viz.: R. Jose said: As they are not permitted to carry on subsequent Sabbaths, so are they also prohibited to do so on that particular Sabbath.
It was taught: R. Hyya bar Joseph said, the Halakha prevails according to R. Jose, and Samuel said: “The Halakha prevails according to R. Jehudah. Did Samuel indeed say so?” Did not R. Jehudah reply to R. Hana of Bagdad that Samuel decreed: “The Halakha prevails according to
R. Jehudah in all cases pertaining to Erubin, but not where partitions are concerned?” Said R. Anan: “Samuel himself explained to me that if the courts were laid open towards unclaimed ground the Halakha prevails according to R. Jehudah but if they were laid open towards public ground the Halakha prevails according to R. Jose.”
MISHNA: If an attic be built over two houses, also if bridges are open at both ends, it is lawful to carry things underneath on the Sabbath. Such is the dictum of R. Jehudah; but the sages prohibit it. Moreover, R. Jehudah further said: It is lawful to combine, by means of an Erub, an alley that is open at both ends, but the sages prohibit it.
GEMARA: Said Rabba: Do not say that the reason of R. Jehudah is because a private ground requires according to biblical law only two partitions, but because he holds (Gud Achith) that the ends of the roofs (in this case of the attic or the bridge) are supposed to reach down to the bottom.
Next: Chapter X: Sundry Sabbath Regulations.