[If] the skylight is smaller than a square handbreadth [and] there is tumah in the house, whatever is directly opposite the skylight remains tahor. [If] the tumah is di-rectly opposite the skylight, the house remains tahor. [If] the tumah is in the house, [and a person] places his foot above [the sky-light], [the person] remains tahor. [If] the tumah is opposite the skylight [and a person] places his foot above [the skylight], R’ Meir declares [him] tamei. However, the Sages say: If the tumah preceded the foot, [the person becomes] tamei; and if the foot preceded the tumah, [he re-mains] tahor. R’ Shimon says: [If] two feet, one above the other, preceded the tumah, and then the first person removes his foot while the second person’s foot remains in place, [the second person] remains tahor, because the first one’s foot preceded the tumah.