Reference for Bava Metzia 203:13

רבא אמר אויר שאין סופו לנוח לאו כמונח דמי

Now if R. Jose son of R. Hanina's dictum is correct, [viz.,] that a man's courtyard effects a title for him even without his knowledge, then when he [the tenant] catches it up from the air, why does it belong to him? Is it not the air of his [the landlord's] courtyard?<span class="x" onmousemove="('comment',' I.e., before it even falls into the tenant's utensil, it must have entered the air of the landlord, and is therefore his. ');">¹²</span>

Jastrow

Jastrow

Rashi on Deuteronomy