THE OBSERVATORIES OF ITALY. 539 



the last few years been manifest in various brilliant discoveries. 

 To show this, it will be sufficient to describe briefly the situation of 

 each observatory, and the work upon which it is at present engaged. 



The Observatory of Palermo : Director^ M. Cacciatore ; As- 

 tronomer^ M. Tacchini. This observatory contains two important 

 instruments: a meridian-circle, constructed in 1857 by Pistor and 

 Martins (of Berlin), whose telescope has an aperture of 126 milli- 

 metres (4.98 inches), and an equatorial by Merz (of Munich), of 24 

 centimetres (9.45 inches) aperture, which, though built in 1857^ was 

 not mounted until 1865. The meridian-circle was employed in 1870 

 to determine the difterence of longitude between Naples and Palermo, 

 this last point being the fundamental station in the new topographical 

 map of Sicily, and it is daily employed in observations of the sun 

 and the principal stars. The most important work, however, of the 

 observatory of Palermo, which is specially undertaken by M. Tac- 

 chini, is the daily study of the solar protuberances. 



Since the total solar eclipse of 1868, a great number of astrono- 

 mers have devoted themselves to the daily observations of these 

 protuberances, in order to study their distribution on the solar cir- 

 cumference, and their relations with solar spots. Among these 

 astronomers are Lockyer, Secchi, Rayet, Respighi, Tacchini, and 

 Young, but it is in Italy that these researches are most vigorously 

 prosecuted, and, in order to avoid the interruptions in a series which 

 cloudy days may occasion, the observatories of Palermo, Rome, and 

 Padua, prosecute these observations in common. 



Every day, when the weather will permit, M. Tacchini makes a 

 drawing of the protuberances surrounding the boi'der of the sun and 

 of the spots and faculae which are upon its surface. These drawings, 

 as well as those made at Rome and Padua, are subsequently pub- 

 lished in the "Memoirs of the Society of Italian Spectroscopists," 

 whose publications, begun in 1872, form already four large quarto 

 volumes. 



For this work, M. Tacchmi makes use of the large equatorial of 

 the observatory, and a direct-vision spectroscope made by Tauber, of 

 Leipsic, which has two series of five prisms. These prisms are of rare 

 excellence, for, in spite of their number, the spectral lines suffer no 

 distortion. The spectroscope can be rotated on its axis so that it can 

 be placed tangentially on any portion of the sun's circumference. 

 Among the interesting historical instruments of the observatory is 

 the altitude and azimuth circle made by Ramsden in l788-'89, which 

 served Piazzi in the preparation of his great catalogue of stars. 



The Observatory of Naples : Director^ M. de Gasparis ; As- 

 tronomers, MM. Fergola, Brioschi, and Nobile. The observatory of 

 Naples is the most important of those of Italy, in its equipment and 

 its personal establishment. 



It was founded in 1812 by Murat, and it is built in agreement with 



