390 Scientific Intelligence. — Meteorology. 



tions might be repeated by making water boil at different heights; 

 and hoped that the improvements made in natural philosophy, 

 might enable the Society of Catania to obtain a more accurate 

 knowledge of the volcano. 



5. Meteor of a Green Colour. — On the night of the 11th of 

 February 1828, between eleven and twelve o'clock, as I was 

 crossing the East River, between this city and Long Island, I 

 observed a beautiful meteor, which was visible for about the 

 space of two seconds. Its course was from a point perhaps 5° 

 below the zenith, toward the horizon in a N.E. direction. It 

 described an arc of perhaps 20°, when it apparently exploded, 

 without any report that I could hear. Its colour was a singu- 

 larly pure grass green, of a hght shade ; the tail which it left 

 was of the same colour, and so were the scintillations which ac- 

 companied its apparent explosion. The latter were distinct, 

 like those accompanying the bursting of a rocket, but by no 

 means so numerous. Two gentlemen who were in the boat 

 with me at the time also saw it. — Silliman's Journal, vol. xiv. 

 No. I. April, 1828. 



6. On ThermO'Barometrical Observatioiis. — M. Horner pre- 

 sented last year, to the Helvetic Society of Natural Science, the 

 results of observations made in January 1827, by M. Esch- 

 mann of Zurich, during an abode of fourteen days on the sum- 

 mit of Rigi, 5520 feet above the level of the sea, for the im- 

 provement of thermo-barometrical observations. There results, 

 from a hundred and twenty observations made evej'y hour, from 

 seven in the morning to nine in the evening, and compared with 

 simultaneous observations made at Zurich, that the height of 

 Rigi above Zurich (which is 702 toises), is without any doubt 

 ten toises greater by the observations made at noon, than by 

 those made in the morning or evening. This results still more 

 evidently from a series of a hundred and eighty-six observations 

 made in June of the same year, only the latter give two toises 

 more for the height. It appears that this augmentation of 

 height, from one hour to another, is connected with the increase 

 of temperature. The evening heights, however, diminish even 

 Avhen the heat still increases. The maximum of height coin- 

 cides pretty well with noon. The summer observations give a 

 height about seven toises greater than those made in winter. It 



