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540 modern ideas. It contains numerous instruments which are maintained in perfect order by the care of an instrument-maker attached to the observatory. In the west meridian room are a transit-instrument by Reichenbach (aperture 117 millimetres $$=$$ 4.61 inches), and a meridian-circle by the same artist (aperture 108 millimetres $$=$$ 4.25 inches). These are still in use, and by means of them M. Fergola has lately determined the differences of longitude of Naples with Rome and Palermo. The east meridian room contains a meridian-circle by Repsold, which has just been mounted, and which is one of the best instruments of this class made by this celebrated artist. The telescope has an aperture of 163 millimetres (6.42 inches), and a focal distance of two metres (8.74 inches). It has a single graduated circle, one metre (39.37 inches) in diameter, and four microscopes.

It is with this instrument that M. Fergola is observing the zone of stars which the observatory of Naples has undertaken for the German Astronomical Society. Besides the three meridian-instruments the observatory of Naples has in active use two equatorials, and is soon to obtain a third of larger dimensions. The first of these instruments was constructed in 1811 by Reichenbach and Utschneider, and has 83 millimetres (3.27 inches) aperture. It is with this small instrument that M. de Gasparis discovered nine asteroids, Ilygea, Parthenope, Egeria, Eunornia, Psyche, Massalia, Themis, Ansonia, and Beatrix. The second equatorial was made by Merz, of Munich, and has 134 millimetres (5.28 inches) aperture, and 2.06 metres (81.10 inches) focal length. The objective is of so perfect a figure that, in spite of its small dimensions, M. Nobile has been able to employ it in the measurement of double stars of Struve's catalogue. (These were discovered by Struve with an objective of 9.62 inches aperture.)

Director, Padre Secchi; Astronomer, Padre Ferrari.—The observatory under the direction of Padre Secchi is built upon the top of the cupola of the church of St. Ignatius, near the Corso; but in so solid a way that the stability of the instruments, during the night at least, is quite satisfactory. The principal instrument of the observatory is an equatorial of 7.5 inches aperture, which is one of the chefs-d'oeuvre of Merz. There is still another equatorial, by Cauchoix, of five inches aperture, which is used for the daily observations of solar spots, and also a transit-instrument by Ertel (aperture 92 millimetres $$=$$ 3.62 inches), for time-determinations. The situation of the observatory, in the centre of the city, has forced its illustrious director to devote his efforts to the study of physical astronomy, which in his opinion is too much neglected in government observatories.

To enumerate the magnificent works executed in this branch of astronomy by Padre Secchi would require too much space, but I may mention a new experimental method used by Padre Secchi in his studies of the solar protuberances. For more than a year he has