Siman - Shabbos Daf 47
- Moving a pan with ashes
R’ Zeira quotes R’ Yochanon who quotes Rebbe Yehuda Hanassi as permitting one to move a pan (which is not muktzeh), even if there are ashes on it (which are muktzeh). This seems to contradict a statement from R’ Yochanon elsewhere, which implied that if a basket only contained a stone then it would become a בסיס לדבר האסור, a base to a prohibited object, and therefore be muktzeh. Why is the pan with the leftover ashes not considered a בסיס לדבר האסור?
Rava explains that Rebbe permitted the pan to be moved because the ashes had been anticipated for later use to cover dirt and therefore the ashes were not muktzeh. Rebbe’s chiddush was that it was permitted to move the pan with the non-muktzeh ashes even if there were muktzeh pieces of wood in it as well.
- Putting a vessel under sparks
The final Mishnah in the perek permits placing a vessel under a lamp on Shabbos to catch the falling sparks. The Gemara asks why this it is permissible to do, given that the falling sparks would make the vessel under the lamp a bosis to muktzeh and it would therefore be a case of מבטל כלי מהיכנו, nullifying the preparedness of a vessel.
Rav Huna the son of Rav Yehoshua answers that ניצוצות אין בהם ממש, sparks have no substance, and therefore the vessel is not considered a bosis to them.
- Olive and sesame gephes
The opening Mishnah of the fourth perek forbids insulating pots before Shabbos with substances that add heat ((מוסיף הבל to the food. One of the substances mentioned is gephes, a certain type of pulp. The Gemara wants to clarify if גפת is referring to olive gephes whose heat is relatively intense, but sesame gephes which is less intense would be permitted to insulate with, or perhaps the Mishnah is referring to sesame gephes, and all the more so, olive gephes would be prohibited.
A statement from R’ Zeira that prohibited placing a box of insulated food on top of olive gephes,was brought to prove that only olive gephes increases the heat of what it is insulating (מוסיף הבל).
The Gemara rejects this proof by saying that sesame gephes also increases heat but is not strong enough to radiate heat upwards to the food on top of it, like olive gephes can.
