Mischna zu Ijow 12:20

If a woman says: "I vow a pair of birds if I give birth to a male child," and she does give birth to a male child, then she must offer up two pairs one for her vow and one for her obligation. If [before she assigned them] she gave them to the priest, and the priest who ought to offer three birds above and one below does not do so, but offers two above and two below, and does not seek guidance, she must she bring another bird and offer that above. This is so if the birds were of the same kind. If they were of two kinds, then must she bring two others. If she had expressly defined her vow, then must she bring three other birds. This is so if the birds were of the same kind. If they were of two kinds, then must she bring four others. If she made a definite fixture at the time of her vow, then must she bring another five birds. This is so if the birds were of the same kind. If they were of two kinds, then must she bring six others. If she gave them to the priest and it is not known what she gave, and the priest performed the sacrifice, but it is not known how he performed it, then she must bring four other birds for her vow, and two for her obligation and one for her hatat. Ben Azzai says: [she must bring] two hatats. Rabbi Joshua said: This is what it meant when they said: "When [the beast] is alive it possesses one sound, but when it is dead its sound is sevenfold." In what way is its sound sevenfold? Its two horns [are made into] two trumpets, its two leg-bones into two flutes, its hide into a drum, its entrails for lyres and its large intestines for harp strings; and there are some who add that its wool is used for the blue [pomegranates.] Rabbi Shimon ben Akashiah says: ignorant old people, the older they become, the more their intellect gets befuddled, as it is said: "He removes the speech of men of trust and takes away the sense of the elders." But when it comes to aged scholars, it is not so. On the contrary, the older they get, the more their mind becomes composed, as it is said: "With aged men comes wisdom, and understanding in length of days."