Talmud for Eruvin 10:7
בּוֹר בִּרְשׁוּת הָרַבִּים, וְחֻלְיָתוֹ גְבוֹהָה עֲשָׂרָה טְפָחִים, חַלּוֹן שֶׁעַל גַּבָּיו מְמַלְּאִין הֵימֶנּוּ בְשַׁבָּת. אַשְׁפָּה בִרְשׁוּת הָרַבִּים גְּבוֹהָה עֲשָׂרָה טְפָחִים, חַלּוֹן שֶׁעַל גַּבָּהּ שׁוֹפְכִין לְתוֹכָהּ מַיִם בְּשַׁבָּת:
A well in the public domain and its chuliah (its surrounding diggings) ten tefachim high — it is permitted to draw (water) from it through a window overlooking it on Shabbath. [Since the chuliah is ten tefachim high, and it is ruled that higher than ten tefachim is not a public domain but a makom p'tur ("a place of exemption"), it is permitted to draw water from it through the window above it on Shabbath. For this constitutes taking from a private domain to a private domain through a makom p'tur. And even if the well is four tefachim removed from the wall of the window, it is permitted to draw water through it, for the public domain does not intervene between the well and the window when he draws water from it, but only a makom p'tur. [Likewise,] (a mound of) refuse in the public domain, ten tefachim high — it is permitted to spill water upon it through a window overlooking it on Shabbath. [For it (the refuse mound) is a private domain, and we do not fear lest the refuse mound be reduced to less than ten tefachim and he come to spill (water) upon it as before. This, only with a public refuse mound, which is not likely to be removed; but with a private mound, which is likely to be removed, it is forbidden to throw (refuse) there on Shabbath, for we fear that he might remove it and render it a public domain.]