Reference for Menachot 188:1

רבי חנינא אמר כמין תיבה פרוצה ר' יוחנן אמר כמין ספינה רוקדת

R'Hanina said, Like a broken box.<span class="x" onmousemove="('comment',' I.e., in the shape of an open box with two of its sides, the front and the back, removed; in other words, each cake consisted of a base and two sides which rose perpendicularly, thus (Fig. 1) .');">¹</span> R'Johanan said, Like a ship's keel.<span class="x" onmousemove="('comment',' Lit., 'a rocking ship'; i.e., like the sides of a ship which narrow downwards until the keel is reached. In like manner the side of each cake narrowed downwards until there was but a fingerbreadth between Fig. 1 them at the bottom; v-shaped. It also appears (v. Rashi) that each side of the cake tapered upwards almost to a point, thus (Fig. 2) . The sides (s) rose upwards at an angle from the dotted lines.');">²</span>

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