Shabbat 26a and Shabbat 26b, a discussion of balsam, pleasant enough of aroma to fear people will take some of the oil from the candle, but also dangerously likely to spark; more kinds of oils acceptable for candles, taking us to a discussion of linen (an exceptional material, in that it’s thought of as a tree, and yet can be used for wicks and is susceptible to ritual impurity), and a discussion of what counts as materials for clothing that can become tamei, at a Biblical level.
