182 Description of a Lake of Sulphuric Acid. 
with 31°95 “gr.” [parts] of caustic ammonia, the muriaté 
of ammonia consists of 
Muriatic acid 61°0554 100:0000 
Ammonia... 38°9446 62°8195 
Ammonia. 
If now 62-8195 parts of ammonia contain 29°454 of 
oxygen, ammonia must consist of 
Ammonium = 53°1133 1000000 
Oxygen.... 46°8867 88'2768 
The phenomena of the decomposition of ammoniacal 
gas by potassium appear to demonstrate that ammonia con- 
tains no compound basis. In this case, hydrogen and ni- 
trogen must be oxides of the same simple substance,—an 
opinion first advanced by Davy, but against which some 
celebrated chemists have adduced a variety of indirect ex- 
periments. I shall insist a little on this subject, which is 
of so much importance in the theory of chemistry, having 
previously adverted to another which is intimately con- 
nected with it. : 
[Be be continued.] 
XXX. Deseription of a Lake of Sulphuric Acid al the Bot- 
tom of a Volcano of Mount Idienne, situated in the Pro- 
‘vince of Bagnia-Vangni, in the Eastern Part of the Island 
of Java. By M. Lescuenauct, Naturalist and Cir- 
cumnavigator in the Employment of the French Govern- 
ment. 
[Concluded from p. 132.] 
Tae volcano is situated in the south-west side of the sum- 
mit of Mount Idienne, which in this place is perpendicu- 
larly cut, Jeaving between it and the gulf a space about a 
quarter of a league in extent. This perpendicular section 
indicates that a part of the summit has been detached by 
the effort which took place at the opening of the volcano ; 
but the chief eruption seems to have taken place at the 
west and north-west parts, for towards the east and south 
we see no considerable traces of it. 
The aperture of the volcano is oval, having its greatest 
diameter directed from NE to SE. I reckon its circum- 
ference taken from the summit to be about half a league, 
its greatest diameter 500 toises, and its depth from the 
highest point about 600 feet. The bottom of the gulf is 
about 250 toises broad, in its greatest diameter: a lake of 
about 200 toises long, the water of which is warm, and of 
a greenish 
