[If] part of a limb projected outside he cuts [it] until he reaches the bone, and pares [the meat] away until he reaches the joint and severs [the limb].  But with other offerings he may chop with a cleaver, for they are not subject to the [prohibition of] breaking a bone.  From the jamb inward is as inside; from the jamb outward is as outside. The windows and the thickness of the wall are as the inside.