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Chapter 4: Laws relevant to insulating food before Shabbos with Muktzah materials
This chapter will discuss the laws of Muktzah which are relevant to the different forms of insulating materials which may be used to insulate ones hot food for Shabbos.
1. What does one do if he insulated using a Muktzah material? 
If one insulated with a material which is forbidden to move, and one now wants to remove the pot from within it on Shabbos, how is this to be done? If part of the lid of the pot is not covered by the insulation, then one grabs on to that part which is uncovered and removes [the cover, this then causes the insulation to entirely fall off the top of the pot and consequently also uncovers the top of the walls of the pot, with which one can grab onto and use to remove the pot with].
The reason the pot does not have the status of a Basis: Now, even though the insulation which is Muktzah is resting on the pot, [nevertheless] the pot is not considered to have become a base for something Muktzah, being that the [purpose of the] lid [of the pot which is being held on to in order to remove the pot] is not at all meant for the insulating material but rather is meant [to be used] for the pot.
[Now, once the cover has been removed] one holds on to the head of the walls of the pot which have become revealed from under the lid, and he then removes the pot entirely from the insulation.
If the lid of the pot is completely insulated: If there is no part of the lid which is not covered [by the insulation], then if one is able to stab a stick or a knife into the lid and then lift it and remove it from the pot, then this is permitted be done, as even though by doing so he is moving the insulation through [moving] the lid, [nevertheless] this does not hold [Halachic] meaning, being that this is considered moving [a Muktzah item] indirectly, which is not [Halachicly] considered to be [under the prohibition of] moving [a Muktzah item], as will be explained in chapter 311 [Halacha 14].
2. What does one do if also the cover of the pot is Muktzah? 
The above [allowance to remove the lid of the pot] is only referring to if the lid of the pot is considered a vessel, and is thus not Muktzah. However if also the lid is made of an item that is Muktzah, then [the cover may not be lifted]. [However] if part of the walls of the pot are not covered by the Muktzah insulation material, enough so one can grab that area with his hands, then one may grab it there and lift up the pot and remove it from the insulation, [thus] having the insulation fall off of it on its own. Afterwards one shakes the pot until the Muktzah lid falls off of it.
The reason that the pot is not considered a Basis: [This is allowed] since the pot has never become a Basis for the lid and insulation, being that the lid and the insulation are there for the purpose of heating up the pot, and not [the other way around] that the pot is there to serve a purpose for them [and thus it does not have a status of a Basis, as an item can only become a Basis if its purpose in being there is to serve the Muktzah item].
3. Rocks and wood that are placed around the oven:
One who places stones and bricks around the Kirah, needs to permanently designate them to be used for this purpose [from now on], in order so it be allowed to move them on Shabbos.
Similarly wood that is designated to be used as fuel, which were used to block the opening of the oven on Shabbos, need to be designated to be always used for this purpose [from now on], as so long as they have not been designated [for the above purposes] they are not considered of importance to him and he [plans to eventually] throw them out, and therefore [they are not considered vessels and] are forbidden to be moved unless one puts them away and designates them for this [purpose]
However those stones which are placed on top of the Kirah, do not need explicit designation, as they are generally [anyways] considered designated to be used.
 Amongst the laws of Muktzah is a law which states that any item which is serving as a base or support for a Muktzah item, then that item also becomes Muktzah, even when in general it is not considered a Muktzah item. Thus here it remains to be understood why it is allowed to remove the pot if the pot is supporting the Muktzah item.
 Meaning the lid of the pot is not considered a basis because an item is only considered a basis when it serves a purpose for the Muktzah item. Thus here since the lid does not serve a purpose for the Muktzah insulation material, and rather the opposite the insulating material is placed there for the purpose of serving the lid [so it stay hot] therefore it is not Muktzah.
 Vetzaruch Iyun from Chapter 309 Halacha 9 where Admur rules that even when it serves benefit from the Basis such as placing a stone to cover a barrel, then it has the status of a basis. See there in the footnotes.
 This applies to any lid that has been either designated for covering, or for any other ready usage.
 Such as if one took a stone and placed it over the pot to cover it.