468 Scientific Intelligence. [June 
The inflammation of the zinc is probably owing to its attaining 
a high degree of heat before it bursts the covering of platina ; 
and its combination with the oxygen of the atmosphere is, there- 
fore, instantaneous. 
Rosert W. Fox. 
X. New Principle in the Seeds of the Cytisus Laburnum. 
MM. Chevalier and Lassaigne have discovered. the existence 
of a peculiar substance in the seeds of the cytisus laburnum, 
which possesses violent emetic properties. They obtained it 
by the following process. The seeds were boiled for some time 
in alcohol. The tincture thus obtained being filtered and evapo- 
rated to the consistence of an extract, the residue was digested 
in water. The aqueous solution was mixed with acetate of lead 
in order to precipitate an albuminous matter which it contained. 
A current of sulphuretted hydrogen gas was passed through the 
filtered liquid, in order to throw down the excess of lead which 
it contained. The liquid thus freed from albumen and lead was 
filtered and evaporated. What remained was the peculiar emetic 
principle of these seeds. Its properties were as follows : 
Its taste was disagreeable. Eight grains of it swallowed at 
‘intervals occasioned vertigos, strong spasmodic contractions, 
flushing of the face, increased the velocity of the pulse, and 
occasioned violent vomiting. These symptoms lasted two hours, 
and left the person who had swallowed the substance in a state 
of considerable debility. Its colour is greenish yellow. It is 
not precipitated by acetate of lead, but itis by subacetate. Itis 
precipitated by nitrate of silver, oxalate of ammonia, and muriate 
of barytes. Emetin, or the peculiar principle of ipecacuanha, 
is not precipitated by these last three reagents. 
The other substances found in the seeds of the cytisus laburnum 
were the following : 
. A fatty matter of a greenish-white colour. 
. Albumen. 
. Green vegetable colouring matter. 
. Malic and phosphoric acids. 
. Malates of potash and lime. 
. Silica in very small quantity—(Journ. de Pharm. Aug. 
1818, p. 340.) i 
XI. On Thermometrical Measurements of Heights, §c.- 
By Mr. Murray. 
(To Dr. Thomson.) 
SIR, Paris, March 28, 1819. 
I should be sorry to condemn an instrument ere its inutility had 
been positively decided; and when I consider its portability 
compared with the common mountain barometer, least of all, 
the thermometer of Wollaston for the determination of altitudes. 
I, therefore, write. this rather with a view to excite observers to 
1 Fay 
Anke WW 
