216 Prof. Dufour: Instructions for the better observation of 
the diminution caused by mere inanition. This fact explains 
the fattening of horses after the administration of small doses of 
arsenious acid, a fact well known to horse-dealers. That quan- 
tity of fat, and of albumen, which corresponds to the depression 
in the secretion of carbonic acid and urea, remains in the body ; 
and if the animal receive adequate nourishment, its weight 
increases. 
XXIX. Instructions for the better observation of the Scintilla- 
tion of the Stars. By Cuares Durour, Professor of Mathe- 
matics at Morges*. 
i ie TIL lately the study of the scintillation of the stars has 
not formed the subject of any series of observations. 
Here and there may be found a few isolated directions, and 
several persons have attempted divers explanations of the phe- 
nomenon, but no continued observations have as yet been pre- 
sented to the learned world. I believe I am the first who has 
undertaken a work of this kind. My observations, commenced 
at Morges in 1852, were at first but a series of gropings in the 
dark, but since 1853 down to the present time, I have never 
allowed one evening to pass in which the stars were visible, 
without carefully observing the scintillation ; and after six years’ 
perseverance in the work, I am convinced that this branch of 
astronomical study is important, and merits a place amongst 
meteorological observations. 
But in order that the results obtained may be more general 
and more complete, it would be very desirable to undertake a 
series of observations analogous to those I have commenced, in 
other climates and under other meteorological circumstances. 
At the time I am writing (December 1859) the following are 
the stations where, I hope, a work of this kind is begun or con- 
tinued. 
Morges (Switzerland), 46° 30" North latitude and 4° 9" longi- 
tude east of Paris—Since 1853 I have taken at Morges nearly 
24,000 observations on the scintillation of the stars. The prin- 
cipal results obtained up to the present time, have been published 
in the reports issued by the Academies of Belgium and Paris, 
the ‘ Notices’ of the Astronomical Society of London, and the 
Bulletin de la Société Vaudoise des Sciences Naturelles. 
The Great St. Bernard, at an altitude of 2480 metres.—The 
monks who inhabit this elevated spot all the year round, on the 
borders of the eternal snow, have willingly undertaken to carry 
on the observations that I commenced there in the summer of 
* Communicated by the Author. 
eden. 
