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THE PLANET JUPITER.

In the view in question it is seen when situated not quitecentrally upon the disc. Indeed, whenever it is upon that sideof the planet which is turned towards the observer, it is so pro-minent a feature of the surface, and so distinct from any other,that it at once rivets his attention. And yet, huge and mostextraordinary as it appears to be, it first began to attract specialnotice so recently as in the summer of the year 1878. Sincethat date it has remained almost unaltered in size, and in itslatitude upon the disc, although it has recently lost some of

Fig . LXVIII.—Jupiter, showing the great red spot on July 9th, 1878, as seen at MorrisonObservatory, U.S.*

the very decided reddish colour by which the astonishmentwhich it at first excited was greatly increased.

It is now generally known as the Great Red Spot. We be-lieve that it was first publicly mentioned by Mr. F. C. Dennett,in the English Mechanic of November 22nd, 1878, who then statedthat he had repeatedly observed it since July 27th of that year.It afterwards proved that Professor Pritchett had seen it in

* Figs. LXVIII.—LXXIII. are taken from the Observatory , vol. iv., bythe kind permission of the Astronomer Royal, who has most liberally lentthe author the original wood-blocks. This is also the case with anotherwood-cut in Lecture XIV.