III. Further observations on the planet Mars

Abstract

The return of Mars to his periodical opposition with the sun has enabled me to offer a few observations on this planet, in addition to those which on a former occasion I had the honour to present to the Society. Among the subjects then suggested for consideration was the permanence of the main features of light and shade which had been recognized by many observers. Another question requiring attention referred to the fogginess or seeming cloudiness of the planet, also noticed by many observers, some of whom represented what might be thought effects of currents in the atmosphere round him.