Sentence:  &#91;[https://books.google.com/books?id=eF9HAQAAMAAJ&pg=PA1 page 1]&#93; That branch of these accessorial rights which confers merely a convenience to be exercised over the neighbouring land, without any participation in the profit of it, is called, by the law of England, <WSD>Easements</WSD>, as rights to the passage of light, air, and water. ... &#91;[https://books.google.com/books?id=eF9HAQAAMAAJ&pg=PA2 page 2]&#93; The origin of some <WSD>easements</WSD> is as ancient as that of property—one tenement may be subjected to the convenience of another by the hand of nature itself—the inferior elevation of one in relation to the other, may subject it to the fall of water from the higher ground. 
Meaning of the word marked with <WSD> tags:  (legal right to use another person's property) The legal right to use another person's real property (real estate), generally in order to cross a part of the property, or to gain access to something on the property.