z;8 OF THE PHÆNOMENA AND AFFECTIONS

Several astronomers have given us exact mapsof the moon, with the figure of every spot, as itpi. xiv. appears through the belt telescopes, distinguish-ing each of them by a proper name. Ricciolidivided the lunar regions among those philoso-phers and astronomers, who have distinguishedthemselves by advancing the knowledge of theheavens, giving the names of the most celebratedcharacters to the largest spots, and those of lesseminence to the smaller. But Hevelius, whodid not approve of this distribution, denoted thedifferent parts of the moon by such geographicalnames, as belong to the several islands, coun-tries, and seas of our earth, without any regardto their situation or figure. The method of Ric-cioli, however, is that which is now generallyfollowed, as the names of Idipparchus, Tycho,Copernicus, &c. are more pleasing to astrono-mers, than those of Africa, the MediterraneanSea, Sicily, and Mount Ætna.

That the spots in the moon, which are takenfor mountains and vallies, are in reality such,is evident from their shadows. Tor in all situ-ations of the moon, the elevated parts are con-stantly found to cast a triangular shadow, in adirection opposite to that of the sun; and, onthe contrary, the cavities are always dark on theside next the fun, and illuminated on the oppo-site one; which is exactly conformable to whatwe observe of hills and vallies on the earth.

And