Reference for Bava Metzia 83:11
ההוא גברא דאפקיד זוזי גבי חבריה א"ל הב לי זוזאי א"ל לא ידענא היכא אותבינהו אתא לקמיה דרבא א"ל כל לא ידענא פשיעותא היא זיל שלים
it can be guarded only [within the void spaces] between bricks. Raba said: Yet Samuel admits [that it may be] hidden] in the wall. But nowadays that there are rappers,<span class="x" onmousemove="('comment',' Who by rapping at the wall can discover its cavities and treasures. ');"><sup>16</sup></span> It can be guarded only in the handbreadth nearest to the earth or to the uppermost beams.<span class="x" onmousemove="('comment',' Asheri a.l. observes that all this held good only in the days of Samuel and his successors, when rappers, diviners, etc. were to be feared. Nowadays, however, we do not fear all this, and it is sufficient if a bailee puts the money entrusted to his charge in the place where he keeps his own. ');"><sup>17</sup></span>