The Taz asks: People rely on moving the tablecloth under the Neiros. It would seem because they hold of Tosfos' ruling that Muktza that was put on Heter only for part of Shabbos, i.e. was intended to be removed in the middle of Shabbos, is not Bosis and may be moved. Why is this different than the candelabra itself? Since we know that the flame will go out in the middle of Shabbos, so the candelabra only had Muktza placed on it for part of Shabbos, so, according to Tosfos, you should be able to move it after the flame goes out.
The Bais Meir answers that a flame is different since it's not in existence when it's get removed from the candelabra. Only an object that is always existing and despite that, it was planned to be removed on Shabbos, do we say that it's not considered as a permanent base for the Muktza and is not Bosis. But something that was left on the Heter for the rest of it's existence, then the very fact that it's not there on the Heter anymore doesn't mean that it wasn't meant as a permanent base.
Rav Akiva Eiger points out from Tosfos that even this Shita only allows to shake off the Muktza that is on it, but not pick up the object while the Muktza is on top of it. Even though if someone forgets a Muktza on a Heter, if you need the space that object is on (and if you shake off the Muktza, it would land in the place you'll need) you're allowed to carry the object with the Muktza on it to a different place, over here is different. Since he purposely left the Muktza on top of the object, we cannot allow you to carry the Muktza, all we allow is to shake it off.
The Magen Avraham quotes a Gemara that a chicken nest that didn't have anything in the Erev Shabbos, and the chicken laid an egg on Shabbos (which is prohibited) in it, the nest is Bosis to the egg. Even though you didn't intend to have the egg in the nest it doesn't make it as you forget the Muktza there, but rather, since the nest is made for eggs, it's as if you intended to put the egg in.
SEIF 4 (CONTINUED)
WHEN IS IT CONSIDERED AS PLACING THE BOSIS ON PURPOSE
Trumas Hadeshen says that Bosis since it's considered as you left it there purposely, is when you put the Muktza on the object on Friday. He takes this from the implication of Rashi that forgetting an object takes place Bein Hashmashes. This implies that if it's put on in the vicinity of Bein Hashmashes (on Friday), then we don't consider that as forgetting, but putting it there on purpose so it should be there on Shabbos. The Bais Yosef argues. That you can learn as long as the forgetting was done during Bein Hashmashes, even if it was placed there right before that on Friday, it's still just forgetting and is not Bosis.
The Shaar Hatzion says that the argument is only when it was put on without any specific intention when you'll remove it. Then the Trumas Hadeshen hold that probably you intended to leave it there for Shabbos and the Bais Yosef holds that it's not sure that was your intention, so you can assume that it's not Bosis. If it was put on specifically to remove before Shabbos and then it slipped your mind to remove it, all agree that it's considered forgetting even if it was placed on Friday.
The Shaar Hatzion ends that from the Rambam implication it seems that he agrees with the Trumas Hadeshen.
SEIF 4 (CONTINUED)
PILING THINGS ON TOP OF EACH OTHER
The Trumas Hadeshen says that from Rashi that says that he wanted to put the Muktza on another object makes it Bosis implies that you definitively wanted it on top of the Heter object. If it's only there on a temporary bases, that you're putting objects in a box, and since there is no room to put everything, you need to pile objects on top of each other, that wouldn't be considered Bosis. But he concludes that it's not conclusive, since you can read the implication to mean that he didn't want to put the object there on Shabbos completely, but if he wanted to leave it there, even in a temporary pile up, it's Bosis.
The Magen Avraham says it's not Bosis. He brings a proof from the case of leaving Trumah Timeah on top of Trumah TiHorah in a box, that you may move the box if you need it's place. We must say that you purposely left it there, because if you just forgot it there, then you're allowed to move it even if only Trumah Timeah was in the box. So we must say that the reason why the bottom fruits where not Bosis is because they were piled up in the box.
The Tosfos Shabbos dismisses this proof. He says that we can say that the case was that he wanted to leave the Timeah in the box on Shabbos, he just didn't want to leave it on top of the TiHorah. Rather, he wanted to switch their positions before Shabbos but forgot to. Therefore if it was only the Timeah, then the box would be Bosis, but since regarding the TiHorah it isn't a Bosis, since you forgot to switch them, so the TiHorah remain Heter. Now the box contains both Muktza and Heter, so it doesn't become Bosis.
But you cannot answer that since like Tosfos we're referring to where the fruits are contained in their own baskets in the box, we'll also says that the Tamea's basket is sitting on the top of the TiHorah's basket, but not on the fruit itself (so the fruit never becomes Bosis.) This is not true, since this is similar to the case of a rock on top of a barrel that the whole barrel and wine is considered Bosis though the rock doesn't rest on the wine. So too here, the TiHorah fruit is Bosis along with the container it's in.
SEIF 4 (CONTINUED)
PILING THINGS ON TOP OF EACH OTHER (CONTINUED)
The Magen Avraham bring another proof to permit objects that have Muktza piled on them. The Gemara permits carrying an incense pot with the ashes (which are Heter since you can use them to cover spit in the house) with the leftover spice woods that didn't get burnt (which are Muktza, since you can't burn them on Shabbos.) From the Rambam it's implied that the wood lie on top of the ashes, and even so the ashes are considered Heter.
The Tosfos Shabbos dismisses this proof. He says that the Rambam anyhow has a printing mistake in it. It says that it can be moved since it's a Gerof Shel Reie (something disgusting) while the real reason is because it's Bosis to both Muktza and Heter. So once you need to change that, we cannot rely that this piece doesn't have other printing mistakes in it, so we cannot assume anything from his implication. The Gemara itself we can say that the wood and the ashes where next to each other, both resting directly on the pot. Rav Akiva Eiger answers that even if the wood was on the ashes, still since the ashes are not one piece, but rather each speck of ash is it's own entity. Even if some wood is on some ash and makes it Bosis, the specks of ash that's between the woods are not Bosis, so you have your Heter there.
The Mishna Brurah says that if needed you can rely on the Magen Avraham. Especially in the case of the tablecloth that's under the candelabra. Since the Bais Meir answers the Taz's question why people are more lenient by this is since the tablecloth is coming to serve the table, to protect anything that would drip on it, and not to serve the lamp. (This is like Rashi's explanation why the cover of a pot not Bosis to the Muktza that is insulating the pot. Since the cover is serving the pot and not serving the insulator, it's not Bosis to the insulator.)
SIEF 4 (CONTINUED)
PUTTING MUKTZA ON SOMEONE ELSE'S OBJECT
The Ohr Zaruah says that if someone puts Muktza on someone else's object it doesn't become Bosis. This is included in the rule that someone cannot make someone else's object prohibited (when it requires intention to prohibit. Obviously, if you throw pork in someone's pot it will prohibit it.)
The Magen Avraham says that if someone puts your bowl under a falling candle to protect your house, then it becomes Bosis. He reasons that we see that something can become Bosis if someone else puts the Muktza on with the owner's knowledge. This is gleaned from Tosfos that explains the case of purposely leaving Muktza on an object in middle of Shabbos (which he obviously cannot do himself, since he's prohibited to move it) by having a Goy or child do it with his knowledge. Knowledge in these cases are not dependant on a command from the owner, as we see that you may not allow a child to put out a fire on Shabbos, since we know his intent is to benefit his father (even if he hadn't commanded him to.)
The Derech Chaim says that if the one who put the bowl to catch the candle had in mind to dump it out in the middle of Shabbos, we can say it doesn't become Bosis. The reason is by combining that it's someone else's action that made the Bosis (so it's not so simple to say it's Bosis) with the Shita of R' Tam that if you intend to remove the Muktza in middle of Shabbos it doesn't become Bosis.
LIFTING BARRELS THAT ARE AMONG OTHER BARRELS
If the barrel that has a stone left on it unintentionally was around other barrels, therefore you cannot tip it over there to drop the stone so not to damage the other barrels, he may lift it and bring it to another place to dump the stone off. Rashi writes "he removes it from among the other barrels and shakes it off." Rav Akiva Eiger says this implies that it must be shook off right away after you get away from the barrels and cannot be moved further with the stone on it. He asks why should this be so? Since the barrel with the Muktza is still in his hand, the Halacha in Simon 308 is that he may move it to where ever he wants and doesn't need to discard it right away. Even the Even Haozer that said this Heter only apply to utensils, since this barrel is a utensil, you should be able to keep on carrying it.