Reference for Shabbat 195:5

א"ר כהנא באטבעי אטבעי היכא מנח להו אגבא דעגלה עגלה גופא מקורה הואי

Now, on the view that the boards were one cubit thick at the bottom, but tapered to a fingerbreadth, it is well:<span class="x" onmousemove="('comment',' As there would be more at the ends than three handbreadths' space between each. ');">⁹</span> but on the view that just as they were a cubit thick at the bottom, so at the top too, what can be said? — Said R. Kahana: (They were arranged] in clasped formation.<span class="x" onmousemove="('comment',' I.e., the four rows were not equidistant. but in two rows (as though clasped) at the head and at the tail of the waggon respectively, this leaving a cubit between them. This was necessary because each row contained three boards, which would give a height of four and a half cubits, and as the thickness was only one cubit they might otherwise topple over. ');">¹⁰</span> Now, where were they placed: on the top of the waggon. But the waggon itself was covered?<span class="x" onmousemove="('comment',' It is assumed that the floor of the waggon was completely closed, like the floor, e.g., of a cement-carrying lorry. How then did Rab state that the space underneath the waggon too was public ground? [The translation follows Rashi's reading and interpretation. R. Han and Tosaf, adopt different readings both here and supra. 'Rab referred to the interspaces', and explain accordingly.] ');">¹¹</span>

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