הלכות מקוואות

These are the substances that intervene with regard to the immersion of keilim: Pitch, mortar, and the like.
When tar is on a cup or a bottle, it is considered an intervening substance if it is on the inside. If it is on the outside, it is not an intervening substance. When does the above apply? To a k'li in a craftsman's shop. When one belongs to a homeowner, whether the tar is on the inside or on the outside, it is an intervening substance.
When there is tar on a large pot or on a bowl, whether it is on the inside or on the outside, whether it belongs to a homeowner or comes from a craftsman's shop, it is considered as intervening.

Musk and black earth are considered as intervening substances, whether in a cup, a bottle, a large pot, or a bowl, whether it belongs to a homeowner or comes from a craftsman's shop.
If pitch or mortar and the like are found on a counter-top, on a table, or on a small chair and they are clean, the foreign substances are considered as intervening, because the owner objects to their presence. If the surfaces are dirty, the foreign substances are not considered as intervening, because he does not object to their presence.

If such substances were on the bed of an ordinary homeowner, they are considered intervening. If they were found on the bed of a poor person, they are not considered as intervening. If they were found on the saddle placed on a donkey belonging to an ordinary homeowner, they are considered intervening. If found on the wineskins placed on a donkey, they are not considered as intervening; on both sides of its saddle-blanket, they are considered intervening.

If pitch, mortar, or the like were found on the clothes of Torah scholars, even on one side, they are considered as intervening substances, because they are careful to keep their clothes clean. If such substances are found on both sides of the clothes of unlearned people, they are considered as intervening. If they are only on one side, they are not considered as intervening.

When oily substances are found on the garments of one who sells such substances, they are not considered as intervening. Similar laws apply in all analogous situations.
If a butcher also sold oily substances and both blood and oily substances were found on his clothes, there is an unresolved question whether they are considered as intervening, because there are two stains, or whether they are not considered as intervening, since this is his work and hence he does not object to their presence.

If tar, mortar, or the like were present on the inside of a sandal, on its upper surface, it is intervening; on its lower surface, it is not intervening. If they were found on a bench, on the upper surface or on the sides, they are intervening. On the lower surface, they are not intervening.

Spots of filth on a chair and a carriage top that have been laundered, whether in the inside or on the outside, whether below or on the sides, are not intervening, because the water will wash them away. Filth coming from dregs left in a cup and a bottle, cotton on the inside of a necklace or inside a bell, and mud or dough on the handle of a hatchet or a rake are not considered as intervening. Should they harden, they are considered as intervening.

It is clear that whenever we have said that tar, mortar, or the like do not intervene for keilim, the rationale is that the owner does not object to their presence. Therefore, if the larger portion of the k'li was covered with tar, mortar, or the like, its immersion is invalid, even though the owner does not object, as we explained. There is no difference in this context regarding any particular type of k'li. Instead, all keilim are the same in this regard.

Whenever the handles of a k'li are hollow and were inserted into a mikveh upside down, they were inserted in the ordinary manner, but they were not thoroughly washed out, or they were of metal and they were bent out of shape, their immersion is invalid.

When one turned the opening of a container upside down and immersed it, it is as if it was not immersed, because the water will not enter it entirely. If a utensil has a portion into which water will not enter unless it is tilted to its side, its immersion is not valid until it is tilted to its side.

When a container was filled with liquids and immersed in a mikveh, it is as if it was not immersed. If the container was filled with water and one immersed it in a mikveh, the water and the container regain purity simultaneously. The rationale is that water can be purified in a mikveh, as we explained in Hilchot Tum'at Ochalin.
If there was urine in the container, it is considered as if it were water. The following rules apply to a container holding water mixed with the ashes of the red heifer. If the greater portion of the container was empty, so that the quantity of mikveh water would be greater than that of the water mixed with the ashes of the red heifer, the container is pure. If not, it is impure, as if the water is another liquid that intervenes between the substance of the container and the water of the mikveh.

When the inside of a container was pure, but the outside was impure, it was filled with white wine or milk, and immersed in a mikveh, the ruling depends on which is the greater quantity. If the greater portion of the container was empty so that there would be more water than milk or wine, it is pure. This leniency is granted, because the impurity is of Rabbinic origin. If it contained red wine or other liquids, the immersion is not effective.

The following law applies to a container that is filled with impure water which had its opening closed with moist mud which was extending into the water of the container. If one immersed it, it is pure. If it was closed with thick mud, it is as if it was not immersed.
Similarly, if a ring was placed in a brick of moist mud and immersed, it is pure. If the brick is made from thick mud, it is as if it was not immersed.

Water need not penetrate through the following articles for their immersion to be effective:
a) knots in the clothes of poor people as a rule; if they are particular about them, they
are intervening; by contrast, as a rule, knots in the garments of homeowners, intervene;
if they are not particular about them, they do not intervene:
b) knots in the fringes of clothes that became tied unintentionally:
c) the loops of sandals:
d) the head tefilah when its cube is firmly attached to its strand;
e) the arm tefilah when it does not move up and down freely:
f) the handles of a leather drinking pouch or a satchel; and
g) any similar entity that is tied or sewed and will not be untied in the future.

Water must be able to penetrate the following articles for their immersion to be effective:
a) the knots in the openings of a cloak which are made like loops;
b) the knots that serve as loops on the shoulder;
c) the border of a sheet that must be extended:
d) the head tefilah when its cube is not attached to its strand:
e) the arm tefilah when it moves up and down freely:
f) the laces of a sandal; and knots in the fringes of clothes that were tied by humans; and
g) any similar entity that will be laid open or extended.
With regard to baskets used in winepresses and olivepresses, if the strands of material that make up the basket are firm, one must scratch out around them. If they are loose, one must shake them out. For their immersion to be effective, water must penetrate into leather pillows and cushions.

Water does not have to penetrate into the inner space of a round leather cushion, a ball, a mold, an amulet, and tefillin for their immersion to be valid. This is the general principle: Whenever it is not common to remove and insert entities in the inner space of an object, it may be immersed while closed.

Whenever the accessories of a k'li are longer than necessary and one will ultimately cut them off, one may immerse them to the extent necessary.
What is implied? For the chain of a large bucket, the measure is four handbreadths; for a small one, ten handbreadths. It is necessary to immerse only this much of the chain, the remainder is pure.

When one placed other keilim in an impure k'li and immersed them together, the immersion is effective for all of them, even if the opening of the k'li is very narrow. The rationale is that the water is able to enter it and since the immersion is acceptable for the larger k'li, it is also acceptable for the keilim inside of it. If he inclined it on its side and immersed it, the immersion is not acceptable for the keilim inside of it unless the opening is as wide as the mouthpiece of a drinking pouch. Similarly, if the larger k'li is pure and one placed impure keilim and immersed them together, the immersion is not acceptable for the keilim inside of it unless the opening is as wide as the mouthpiece of a drinking pouch.
When does the above apply? With regard to terumah, but with regard to consecrated food, keilim should not be immersed inside pure keilim at all, even if they were in a basket or a storage bin, as explained in its place.