" Apri120, 10b 2T, sidereal time. The volcano burns with greater violence than last night. Its diameter cannot be less than 3", by comparing it with that of the Georgian planet : as .Jupiter was near at hand, I turned the telescope to his third 'satellite, and estimated the diameter of the burning part of the volcano to be equal to at least twice that of the satellite : whence we may compute, that the shining or burn ing matter must be above three miles in diameter. It is of an irregular round figure, and very sharply defined on the edges. The other two volcanoes are much thr ther towards the centre of the moon, and resemble large, pretty faint nebula, that arc gradually much brighter in the mid dle ; but no well defined luminous spot can be discerned in them. These three spots are plainly to be distinguished from the rest of the marks upon the moon ; for the reflection of the sun's rays from the earth is, in its present situation, suffici ently bright, with a ten feet reflector, to show the moon's spots, even the darkest of them ; nor did I perceive any similar phenomena last lunation, though I then viewed the same places with the same instrument.
" The appearance of what I have called the actual lire, or eruption of a volcano, exactly resembled a small piece of burn ing charcoal when it is covered by a very thin coat of white ashes, which frequently adhere to it when it has been some time ignited ; and it has a'degree of brightness about as strong as that with which such a coal would be seen to glow in faint day light. All the adjacent parts of the vol canic mountain seemed to be faintly illu minated by the eruption, and were gra dually more obscure as they lay at a great er distance from the crater. This erup tion resembled much that which I saw on the 4th of May, in the year 1783, but differ ed considerably in magnitude and bright ness ; for the volcano of the year 1783, though much brighter than that which is now burning, was not nearly so large in the dimensions of its eruption : the former seen in the telescope resembled a star of the fourth magnitude as it appears to the naked eye ; this, on the contrary, shows avisible disc of luminous matter very dif ferent from the sparkling brightness of star light."