Then towards the equator, with a latitude of 5 deg.

north and a longitude of 25 deg.

west, appears _Mare Tranquillitatis_, the Sea of Tranquillity, occupying about 180 thousand square miles.

This communicates on the south with _Mare Nectaris_, the Sea of Nectar, embracing an extent of about 42 thousand square miles, with a mean latitude of 15 deg.

south and a longitude of 35 deg.west.Southwest from _Mare Tranquillitatis_, lies _Mare Fecunditatis_, the Sea of Fertility, the greatest in this hemisphere, as it occupies an extent of more than 300 thousand square miles, its latitude being 3 deg.