266 On definite Proportions, 
more powerfully than hydrogen does, this. quadruple com- 
bination of sulphur, metal, oxygen, and hydrogen may take 
place, and all the component parts exist in such propor- 
tions, that, when taken in pairs, they stand in the same 
degree of combination, however they may be divided. If, 
on the other band, the metallic body bas a weaker attrac- 
tion to oxygen than hydrogen has, the combination with 
the hydrotheic acid is-impossible; the hydrogen forms 
water with the oxygen, and the metal a sulphuret with the 
sulphur. Alkalis, alkaline earths, the protoxides of zinc 
and of manganese, afford saline combinations with sulphu- 
reted hydrogen; while most of the oxides of the older 
metals, for instance, the oxides of lead and un, are only 
reduced to sulphurets by it. 
3. Does Ammonia contain Oxygen or not ? 
If we grant_the affirmative, we have already determined 
its composition as accurately as our modes of analysis ad- 
mit. Since, however, many distinguished chemists assert 
the negative, we shall examine the probability of each 
opinion ; for in this case we must be satisfied with proba- 
bility only. . 
Tf ammonia contained no oxygen, we should be obliged 
to consider it-as a base comparable to sulphureted hydrogen 
as an acid, there betag no oxygenization in either case, 
But whence should we derive, on this snpposition, its pro- 
“perty of becoming a base, or its alkalescence, since hydro- 
gen does not possess this property, and since nitrogen, its 
other component part, 1s a substance of an opposite nature ? 
Nitrogen stands with sn!phur, phosphorus, and arsenic, in 
a series of bodies which form the strongest acids, and 
which are attracted by the positive pole of the electric cir- 
cle. It has been observed indeed that sulphur, phosphorus, 
carbon and arsenic are sometimes deposited at: the me- 
gative pole, and cannot appear at the positive pole: this 
however only happens in the presence of water, at the ex- 
pense of which these bodies are oxygenized ; and in come 
parison with oxygen all bodies tend to the negative, pole. 
{ call all those bodies [negative], which either alone, or 
jn combination with oxygen, are capable of being attracted 
by the positive pole; and those [positive], which when 
combined with oxygen cannot collect at the positive pole, 
and are repelled by it when they have been formed, and in, 
a short time either reduced, or collected at the negative, 
pole; for example, the metallic pies which are some- 
times formed at the positive wire? [Negative] bodies are 
in general so [negative] that they never constitute the panes 
o 
