ancient lights

Noun

 * 1)  The right, based in English common law, of a property owner to retain an accustomed, unobstructed view and satisfactory illumination from his or her window(s), restricting nearby construction that would obstruct such a view or such illumination; the window(s) providing such an accustomed view or satisfactory illumination.
 * 2) * 1823, Sir William Blackstone (author), Vincent Wanostroch (editor), The British Constitution, or an Epitome of Blackstone's Commentaries on the Laws of England, for the Use of Schools, p. 403 (Google preview):
 * If a house or wall is erected so near to mine that it stops my ancient lights, which is a private nuisance, I may enter my neighbour's land, and peaceably pull it down.
 * If a house or wall is erected so near to mine that it stops my ancient lights, which is a private nuisance, I may enter my neighbour's land, and peaceably pull it down.