Reference for Bava Batra 150:15
ושמואל אמר אנא דאמרי אפילו כתנא קמא עד כאן לא קאמר תנא קמא אלא בבעלי חיים דכיון דמיעקרא יד ורגל אידך למיעקר קיימא אבל ספינה אי משיך לה כולה אין אי לא לא
— Rab can tell you: What I have said [is valid] even according to R. Aha. For his statement ['until it moved etc.'] is applicable only to an animal,<span class="x" onmousemove="('comment',' Lit., 'living beings'. ');"><sup>36</sup></span> which, though it has moved a foreleg and a hind leg, remains in the same place;<span class="x" onmousemove="('comment',' The body. resting on the other legs, does not move from its position. ');"><sup>37</sup></span> but [in the case of] a ship, when a small part of it moves the whole moves. And Samuel can say: What I have said [is valid] even according to the first Tanna. For his statement ['as soon as it has moved, etc.'] is applicable only to an animal;<span class="x" onmousemove="('comment',' Lit., 'living beings'. ');"><sup>36</sup></span>