Reference for Shabbat 248:18
הא רבי יהודה הא רבי שמעון הא רבי נחמיה
One [Baraitha] taught: We may heat with utensils, but not with fragments of utensils; another was taught: Just as we may heat with utensils, so may we heat with fragments of utensils: whilst a third taught: We may heat neither with utensils nor with fragments of utensils. One agrees with R. Judah, one with R. Simeon, and the last with R. Nehemiah.<span class="x" onmousemove="('comment',' (i) R. Judah: both mukzeh and nolad are forbidden, hence the prohibition of fragments. (ii) R. Simeon: mukzeh and nolad are permitted, hence both fragments and vessel are permissible; (iii) R. Nehemiah: a utensil may be handled on the Sabbath or Festival only for its normal function, hence the prohibition of both. ');"><sup>33</sup></span> R. Nahman said: The bricks that are left over from a building may be handled, since they are fit to sit on.<span class="x" onmousemove="('comment',' And the last few may possibly be kept for that purpose. ');"><sup>34</sup></span>