|Base price||2 zm|
|Monster use||Will not be used by monsters.|
A sack stores items beyond the 52-character limit, and protects its contents from fire, cold, and many other forms of damage. However, throwing a sack may break or damage some of its contents; also, if a sack gets wet (e.g. from falling into a pool), it contents may become wet as well.
Sacks are passable for simply carrying more items than usual, and can be greased to offer some protection against water damage, but are generally replaced with an oilskin sack or a bag of holding; the former keeps items dry without the need for grease, while the latter offers weight reduction (lowering or preventing encumbrance) and magically protects contents from breakage. Even once you have one or both of those, sacks still have some uses; they can store emergency items, such as holy water or a scroll of scare monster, separately from the rest of your items so that you can #tip them out when needed.
The most important use is storing a wand of cancellation, which causes an item-destroying explosion if placed into a bag of holding; the wand may also be used to uncurse a bag of holding if necessary. While an oilskin sack can also work for this purpose, they are redundant since wands are not adversely affected by water, and sacks are generally more common. In addition, a sack can also be used to contain a bag of holding and protect it against being cursed to begin with. Nested sacks with a bag of holding at the core also offer the possibility of reducing the weight of loot for extra points when you ascend; the risk of an explosion is still possible, albeit with a reduced chance. See Bag of holding § Nesting bags of holding for more on this tactic.
"Now, this third handkerchief," Mein Herr proceeded, "has also
four edges, which you can trace continuously round and round:
all you need do is to join its four edges to the four edges of
the opening. The Purse is then complete, and its outer
"I see!" Lady Muriel eagerly interrupted. "Its outer surface
will be continuous with its inner surface! But it will take
time. I'll sew it up after tea." She laid aside the bag, and
resumed her cup of tea. "But why do you call it Fortunatus's
Purse, Mein Herr?"
The dear old man beamed upon her, with a jolly smile, looking
more exactly like the Professor than ever. "Don't you see,
my child--I should say Miladi? Whatever is inside that Purse,
is outside it; and whatever is outside it, is inside it. So
you have all the wealth of the world in that leetle Purse!"