The Astronomical Register. No. 179. NOVEMBER. 1877. OPTICAL SPECTROSCOPY OF THE RED END OF THE SOLAR SPECTRUM AT A HIGH ALTITUDE IN THE SKY. PART III.- OBSERVATIONS AT LISBON. Violently up and down hill is the city of Lisbon, excepting only the winding strand along the Tagus shore, and the ominouslooking valley of the great earthquake of 1755, the grave of 30,000 citizens. Ominous still; for the line of that valley is more marked than concealed by the rectangular blocks of renewed street architecture hastily run up by Count Pombal to fill the vacancy; and, with all the modern houses, so engineered it is said, as to keep up the floors and roofs, though the filling-up masonry of their walls may fall, when the next equally powerful shock shall take place. But that calamitous valley runs northward from the river's bank, near the eastern end of the city and just short of the old Roman buildings at the foot of the castle hill, while all our attention on the morning of July 11 was directed westward, driving right through the Lusian metropolis, even out at its western, or Alcantara, gate; and then partly by the Belem road, reaching a cross lane which conducts between winding garden walls to the south-west entrance of the Ajuda Park, "Tapada de Ajuda," in the midst of which regal and carefully secluded domain stands the Royal Observatory of the country. Much to be distinguished from the educational astronomical observatory of the Polytechnic school, on one hand, (though that is an extremely well furnished and fitted observatory, with three domes, two meridian, and other library and laboratory rooms), and on the other hand from the meteorological observatory of the Infante Dom Luis, in the heart of Lisbon-is this western Royal Observatory thereof; for it is devoted to high astronomy and the development thereof, alone. Its building is not indeed quite finished yet, but is growing day by day into full condition for VOL. XV. |