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Rh his stay there to astronomical work. The nebula of Orion of course attracted much of his attention, and on account of its favorable situation for observation he was enabled to examine it to much better advantatage than in England. In the "Astronomical Observations at the Cape of Good Hope," Herschel has given a figure of the nebula as he saw it (see Fig. 3), and has added an account of its appearance, a portion of which account we shall quote.

Fig. 5 is a representation of the small stars immediately in the vicinity of the trapezium as seen by Herschel.



It is easily seen that the circumstances at the Cape of Good Hope were much more favorable than they had been in England: this is witnessed in the figures here given by the greater number of stars shown, and in the original drawing by the amount of detail in the features of the nebula itself. The nebulosity surrounding θ Orionis was traced by Herschel over half a square degree of space, and numerous points of doubt were settled. In his account Herschel states that he discovered the sixth star of the trapezium in 1832, and he expresses his surprise that Struve, who had examined the stars in this neighborhood frequently, should have overlooked it.

Da Vico, of the Roman College, had in 1839 declared that he had seen the stars within the trapezium (an assertion which has been repeated since by various observers, good and bad), and Herschel takes the opportunity to declare that not only had he seen no stars there, but that the absence of any trace of star or even of nebulosity