Reference for Eruvin 175:20

<big><strong>גמ׳</strong></big> מ"ט אמר רבה מפני שאדם עשוי להסתפק סאתים מים בכל יום בארבע אמות אדם רוצה לזלפן

INTO IT ON THE SABBATH,<span class="x" onmousemove="('comment',' Because all the water that is likely to be poured into it during the Sabbath would, as a rule, be absorbed before it reached the public domain. If some of the water should, for any reason whatever, run into the public domain no transgression would be committed since the tenants' intention was that it shall be absorbed before it reached the public domain and no transgression is involved where one's intention was not fulfilled. Particularly is this the case here where Pentateuchally it is permitted ab initio to pour water into a private domain though one's intention was that it should ultimately find its way into the public domain.');">⁴⁵</span> BUT THE SAGES RULED: EVEN WHERE A ROOF OR A COURTYARD WAS A HUNDRED CUBITS IN AREA,<span class="x" onmousemove="('comment',' A stretch sufficient to absorb all the water that can possibly be poured out in one day.');">⁴⁶</span> NO WATER MAY BE POURED DIRECTLY OVER THE MOUTH OF THE DRAIN,<span class="x" onmousemove="('comment',' The reason is given in the Gemara infra.');">³⁶</span> BUT IT MAY BE POURED UPON THE ROOF FROM WHICH THE WATER FLOWS INTO THE DRAIN. THE COURTYARD AND THE EXEDRA MAY BE COMBINED TO MAKE UP THE PRESCRIBED FOUR CUBITS. SO ALSO IN THE CASE OF TWO UPPER STOREYS OPPOSITE EACH OTHER<span class="x" onmousemove="('comment',' Between which there was a courtyard whose area was less than four cubits.');">⁴⁷</span> THE TENANTS OF ONE OF WHICH<span class="x" onmousemove="('comment',' Lit., 'some of them'.');">⁴⁸</span> MADE A TROUGH<span class="x" onmousemove="('comment',' In the courtyard.');">⁴⁹</span> AND THOSE OF THE OTHER DID NOT, THOSE WHO MADE THE TROUGH ARE PERMITTED TO POUR DOWN THEIR WATER,<span class="x" onmousemove="('comment',' Into the courtyard below.');">⁵⁰</span> WHEREAS THOSE WHO DID NOT MAKE ANY TROUGH ARE FORBIDDEN. <big><b>GEMARA: </b></big>What is the reason?<span class="x" onmousemove="('comment',' That IF THE AREA OF A COURTYARD WAS LESS THAN FOUR CUBITS NO WATER MAY BE POURED OUT INTO IT and, inferentially, that if the area was four cubits or bigger water may be poured out into it.');">⁵¹</span> - Rabbah<span class="x" onmousemove="('comment',' MS.M. Alfasi and Asheri read 'Raba'; Bomb. ed. 'Rab'.');">⁵²</span> replied: Because a man is in the habit of using up two se'ah of water daily, and in an area of four cubits<span class="x" onmousemove="('comment',' During the summer, the season to which this Mishnah refers (cf. infra) , when courtyards are dusty.');">⁵³</span> he is inclined to spray it<span class="x" onmousemove="('comment',' As his intention is not to have the water running into the public domain but to spray on the floor of' the courtyard it is permitted to pour it out in that courtyard though sometimes it might eventually find its way into the public domain.');">⁵⁴</span>

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