Siman - Eruvin Daf 87
- Drawing water from a four-by-four tefach hole
It was learned in a Baraisa that Rebbe Chananya ben Akavya says, גזוזטרא שיש בה ארבע אמות על ארבע אמות - A balcony which is four by four amos in size, and extends over water, חוקק בה ארבעה על ארבעה וממלא – one cuts a square hole of four tefachim by four tefachim in the center of it and he may then draw water through this opening. Rashi explains that the solid segments that remain on each side of the hole are viewed conceptually as having been bent down, forming a ten tefach high enclosure below the hole. These partitions are then projected downwards to enclose the surface of the water, using the principle of gud achis.
Rabbah suggested that Rebbe Chananya and Rebbe Yehudah held identical things since Rebbe Yehudah also held gud achis works, such as in the case of a wall over the cistern. Abaye said that this is not necessarily so. Perhaps Rebbe Yehudah holds gud achis works to extend walls downward but would not go as far as to say that one may conceptually “bend” the segments of the balcony to form suspended partitions. And perhaps Rebbe Chananya was lenient only with regards to the Sea of Teverya, because it has high banks, cities and karpafs which surround it, but gud achis would not work with other bodies of water.
- A water canal passing through a chatzeir
The next Mishnah states, אמת המים שהיא עוברת בחצר – If a water canal passes through a chatzeir one may not draw water from it on Shabbos unless they erected a mechitzah ten tefachim high, within the canal at its entrance to the chatzeir and at its exit from it. Rashi explains that although a suspended mechitzah is valid over water, it must be evident that the partition was erected for the water. Therefore, the water’s mechitzah must be within the banks of the canal, and the walls of the chatzeir that pass over the canal do not permit it. Rebbe Yehudah says, כותל שעל גבה תידון משום מחיצה – The chatzeir wall which passes over the canal at each end may be considered a partition.
- טומנין בעצה
A Baraisa is brought that teaches three lenient rulings issued by Chananya ben Akavya for the people of Teverya. The first was regarding drawing water from a balcony on Shabbos via the conceptual bending of walls mentioned above. The second one was טומנין בעצה, he permitted them to store fruit in bean stalks wet with dew. He held that the people of Teverya would collect the extra stalks from the crop early in the morning, so that they would not miss work later in the day, not because they were interested in the stalks being wet with dew. Therefore, the dew is not מכשיר לקבל טומאה and the fruit can be stored in these wet stalks without becoming susceptible to tumah.
