Reference for Eruvin 119:1

ולא עירבו אם יש לפניהם דקה ארבעה אינה אוסרת ואם לאו אוסרת

to prepare an 'erub<span class="x" onmousemove="('comment',' Jointly for the balcony and the courtyard, but each was provided with a separate 'erub.');">¹</span> the latter does not restrict freedom of movement in the former if a barrier, four handbreadths in height, intervened between them,<span class="x" onmousemove="('comment',' Lit., 'before them', sc. at the foot of the ladder. The door forms a partition between the two courtyards so that the residents of the one can in no way affect those of the other.');">²</span> otherwise it does impose a restriction?<span class="x" onmousemove="('comment',' As if the ladder were a proper door communicating between the balcony above and the courtyards below. From this it follows that, according to R. Nahman, a ladder has the status of a door where such status leads to a restriction of the law; how then could it be said supra that he held a ladder to have the status of a wall where the law is thereby relaxed?');">³</span>

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