1. A fire does not have a Techum.
2. Similarly, one does not transgress Me'ilah according to Torah law if he uses a fire of Hekdesh.
3. The Beraisa states five differences between a coal and a fire. Three of them are the laws in our Mishnah.
4. The Mishnah discusses the Techum of water taken from a well.
5. A well used as a public water source for people coming up from Bavel has the Techum of anyone who uses it.
A BIT MORE
1. Accordingly, if someone lit his candle from his friend's candle on Yom Tov, he may carry it anywhere within his Techum even when it is outside of his friend's Techum.
2. This is because a fire is not considered to be a physical object (this is the reason for #1 as well). However, if he uses a hot coal of Hekdesh, he transgresses Me'ilah.
3. One law is that a coal of idolatry is forbidden from benefit while a fire of idolatry is permitted. The other is that a person who swears that he will not have benefit from someone may not benefit from his coal but may benefit from his fire.
4. If it is a privately-owned well, the water has the Techum of its owner. If it is a public city well, it has the Techum of that city.
5. Since the water is ownerless, anyone may use it. Accordingly, its Techum is that of the person who draws it from the well.