Reference for Niddah 4:39

מאי שנא הכא ודאי ומ"ש הכא ספק

a wine jug for the purpose of periodically taking from it <i>terumah</i> [for wine kept in other jugs]<span class="x" onmousemove="('comment',' In order that he might be allowed to use the wine in the other jugs he keeps this one jug for the purpose of taking from it daily, or whenever required, the appropriate quantity of wine as terumah or tithe for the wine in the other jugs. ');">³⁶</span>

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