Reference for Eruvin 168:3

אביי אמר כגון דקיימין בתוך עשרה דהדדי ולא מיבעיא קאמר לא מיבעיא עשו לתחתונה ולא עשו לעליונה דאסירי דכיון דבגו י' דהדדי קיימין אסרן אהדדי

to fill their buckets by way of the upper one.<span class="x" onmousemove="('comment',' So that both groups of tenants use the hole in exactly the same manner both lowering and none thrusting their buckets.');">⁹</span> Abaye replied: This is a case where the balconies were situated within ten handbreadths from each other,<span class="x" onmousemove="('comment',' Sc. the position of the upper balcony was by less than ten handbreadths higher than the lower, in consequence of which there can be no existence for a third domain between the two, the use of which should be allowed to the one or the other of these two adjacent domains. A third domain of such a character is possible only where the two adjacent domains were separated from each other by a trench, or a wall that was ten handbreadths deep or high or by a space of similar height.');">¹⁰</span> but<span class="x" onmousemove="('comment',' In reply to the possible objection: If the prohibition of the use of the hole is due to the proximity of the balconies and not to the manner in which use of it was made, why was the ruling limited to the case where 'a partition was made for the upper one seeing that the same ruling should apply even where it was made for the lower one?');">¹¹</span> the ruling is to be understood to be in the form of 'not only but':<span class="x" onmousemove="('comment',' Lit., 'and he implied (the formula) it is not required'.');">¹²</span>

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