Selenographers are not quite agreed as to the nature of these colors.

Not that such colors are without variety or too faint to be easily distinguished.

Schmidt of Athens even says that if our oceans on earth were all evaporated, an observer in the Moon would hardly find the seas and continents of our globe even so well outlined as those of the Moon are to the eye of a terrestrial observer.

According to him, the shade of color distinguishing those vast plains known as "seas" is a dark gray dashed with green and brown,--a color presented also by a few of the great craters.
This opinion of Schmidt's, shared by Beer and Maedler, Barbican's observations now convinced him to be far better founded than that of certain astronomers who admit of no color at all being visible on the Moon's surface but gray.

In certain spots the greenish tint was quite decided, particularly in _Mare Serenitatis_ and _Mare Humorum,_ the very localities where Schmidt had most noticed it.