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258 of them known), and certainly we in America, who have Peters and Watson among us, have no cause to wonder at such discoveries.

Neptune was discovered first by two theoretical astronomers in their studies, and the delight with which the news of the actual discovery was received was a tribute to the power of pure analysis, and in nowise contributed to the glory of telescopic research.

The startling discoveries, as we have seen, were reserved for the early astronomers, who first found the new country, leaving their successors to accurately map it out. The lesson of patience which can be learned from the labors of these successors is no mean one. To this patience, supplemented by a skill which usually must be of a high order, we owe the later discoveries of the telescope, such as the finding of the eighth satellite of Saturn (by Bond and Lassell), and of the two interior moons of Uranus (Lassell, 1847 and 1851), and of the satellite of Neptune.

There is hardly an object in the whole heavens—planets, of course, excepted—which has been so thoroughly and faithfully studied as the Great Nebula in Orion. And this nebula has a history which will well repay a study somewhat in detail. We shall, in comparing the different work already done upon it, arrive at a very good idea of the progress of telescopic astronomy itself, since, for over 200 years, the details of this nebula have been a subject of solicitude to a great number of eminently skillful astronomers, aided by the best telescopes of their time.

The nebula was discovered by Huyghens in 1656, and in our own century it has been studied by the great reflectors of Herschel and Rosse, and by the refractors of Cambridge, Pulkova, and Rome, in the hands of Bond, Struve, and Secchi.

The place of this nebula in the heavens is easily to be found by any one tolerably familiar with the aspect of our winter sky.

The constellation of Orion is a well-known and brilliant asterism, and very conspicuous among the other stars of the group are the three stars which constitute the "belt." Below these are three others, in nearly a straight line, and these are known as "the sword:" the northern star of these is C Orionis; the middle one is? Ο (Theta) Orionis; and the southern is? ι (Iota) Orionis; it is of the nebula surrounding? Orionis that we wish to speak.

Flamsteed, astronomer-royal of England, marked Orionis in his catalogue of stars, as of the fourth magnitude, and to the naked eye it so appears.

But, on examination with a telescope, this star is seen to be not single, but multiple. When Huyghens, in 1656, turned his newly-constructed telescope to it, he saw three stars, and these were surrounded by a cloud-like mass—the nebula.

The figure which he printed in his "Systema Saturnium" is given (Fig. 1, p. 259), together with the figure of the French astronomer,