confused by unnecessary repetitions, and voluminous tables, that a man must be pretty conversant in these matters, to trace and combine the facts, so as to check the conclusions, which would consequently be taken upon trust by the generality of readers, unless publicly contradicted. As it will be my endeavour so far to avoid the use of all terms of art as to make the subject generally intelligible, I flatter myself I shall not be thought impertinent for giving a short explanation (though quite unnecessary to the far greater part of my readers) of what the Longitude is, and what the service required of the Watch.[1]
The Longitude of any place is its distance East or West from any other given place; and what we want is a method of finding out at sea, how far we
- ↑ The ensuing paragraph would have been left out, had not Mr. Mudge, admiring it for its clearness, given it insertion in his reply: and also by reason that in a work adapted as far as the writer could effect it, for general perusal, it may be of use to some tyros; and occasionally serve to make the Ladies distinctly acquainted with a word so often in their way, on taking up a newspaper. They will please to observe that four seconds of time are equivalent to a geographical mile, rather more than a statute mile, in space; which gives fifteen such miles to a minute, and sixty, or a degree, to four minutes. By the same progression, the earth revolves 21,600 miles at the equator in the twenty-four hours; but the motion of our globe on its polar axis becomes trifling when compared with its velocity in its orbit, for Mr. Whiston tells them—that while he is writing, himself and his study are carried at the rate of 25,000 miles an hour!
