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 the north, you will add the altitude you have taken to the sun's declination that day, and act according to the second rule. 5. When you have an altitude of 90 deg., you will be so many degrees distant from the equator as there are degrees of the sun's declination, and if the sun has no declination you will be under the equator. 6. If you are to the north of the equator, and the sun is in the southern signs you will look what is its declination, you will add these degrees of declination to those of the altitude observed, and as many degrees as are wanting from 90 deg., so many will you be distant from the equinoctial. 7. You will do the same when you find yourself to the south of the equinoctial, whilst the sun is in the northern signs.

"Longitude indicates the degrees from east to west: I have considered many methods or means for ascertaining it, and I have found three methods fitting for that object. The last is the most convenient for those who do not know astrology. At the present time the pilots content themselves with knowing the latitude; and are so proud that they will not hear speak of longitude.

" From the latitude of the moon the longitude is calculated of the place in which the observation is made. The distance of the moon from the ecliptic is called its latitude: the ecliptic is the path of the sun. The moon, in its movement, always increases its distance until it reaches the furthest point of its distance: and thence it returns back, to diminish, so to say, its latitude, until it is with the head or tail of the dragon there it cuts the ecliptic. And since