448 F. H. Storer—Ferment-theory of Nitrification. 
accord with the important fact observed by Warington, that 
darkness* is essential to the action of the nitrifying germs, for 
although my bottles were not shielded from cise’ Gay hans 
the mixtures of peat and water which the tained were 
practically dark-colored muds, not ill-fitted to Moles the germs 
from the light. 
It is possible of course that the colder weather which pre- 
vailed during the later trials may have had an influence upon 
their results; but if this be so, the fact must be counted as an 
additional argument in favor of the ferment-theory. More- 
that is needed to induce nitrification, the heating of the liquids 
by day in the third series of experiments would have been suf- 
he ie though both the strong heat and the cooling of the 
nies would have tended to prevent the growth of 
ee organism 
the Coca of the ferment-theory, it would have been 
well to control the meen: ew above given by trials with 
mixtures of the purified peat and carbonate of lime, for peat 
ich has been treated ah muriatic acid has always a slight 
wed reaction, due I suppose to free humic acid, no matter how 
thoroughly it may have been washed with water, and it is to 
be supposed that this acid peat, devoid withal of phosphatic 
and other saline matters, is not favorable for the growth of the 
ferment. But as was said before, my experiments were made 
to test the oxidizing action of certain chemicals, not to culti- 
vate living organisms. 
It may be added that I have not as yet found any evidence 
* The following statement has a certain interest for analysts as bearing U 
the stability of dilute solutions of — pps chloride. In February, 187 sy 7a 
it was 
noticed by my assistant, Mr. Lewis, solution of ammonium chloride which 
had been prepared ten or twelve ase previously for use in connection with 
Nessler’s test, by dissolving the salt at the rate of 3°15 grams to the liter, now 
gave a strong reaction for nitrites, although f a solutions, made in 
the same way from like ma gave no reaction. e old solution was con- 
tained in a glass-stoppered bottle which was about cae filled by it, and it had 
n kept most of the time in a as cupboard. 
Acting on the supposition that the change of the ammonium salt to a 
had been caused by the growth of some fungus in the liquid and that sale fun- 
gus might pickers be Le at in other bottles in the neighborhood, I a as 
many different specimens of moulds as could be found growing in the various 
saline soltions apt kept in in th the laboratory, and, after sliding with pure water, "placed 
them in a series of half-gallon bottles, into which had been poured from half to 
