41 
coloring matter of the fungus. As a matter of fact, he found in the 
expressed sap of this and other fungi, notably in Agaricus sanguineus , 
an organic matter which has this remarkable power of transform- 
o 
ing ordinary oxygen (O), into ozonized oxygen, O, and of forming 
with the latter a compound analogous to lead peroxide (PbO + O), 
o 
which readity gives up this active oxygen, O, to a number of easily 
oxidizable substances, both organic and inorganic, among them 
guaiacum and the chromogenic substance of Boletus luridus. 
He observed, further, that after having been deprived of its active 
oxygen, this peculiar compound may be charged with it again by 
simply passing a current of air through its solution. He then goes 
on to say that this peculiar substance may well be compared with 
nitric oxide, which enjoys to a remarkable extent the power of 
instantaneously transforming inactive oxygen, (O), into active oxygen, 
0, thereby forming a peroxide containing O, and from which this pe- 
culiar form of oxygen may easily be transferred to a multitude of ox- 
idizable substances. In other words, in addition to the chromogenic 
substance which it contains and through whose oxidation it ultimately 
becomes blue, the Boletus luridus and other fungi, notably the Aga- 
ricus sanguineus , contain a substance capable of ozonizing the oxy- 
gen of atmospheric air; in other words, they contain a Sauerstoff- 
erreger, or oxygen-exciter. This substance enters into a loose com- 
bination with the ozone thus produced, forming therewith a compound 
analogous to a peroxide containing active oxygen, which in turn 
is capable of giving up its active oxygen to guaiacum or to the chro- 
mogenic substance contained in the fungus itself, thus turning it 
blue. In other words, the substance responsible for the bluing of 
the chromogenic substance contained in the boletus is not only a 
Sauerstofferreger but also a Sauer staff trdger, or a true carrier of oxygen. 
Schoenbein was also impressed with the instability of these remark- 
able Sauerstofferregern and Sauer stofftrligern of the plant world. 
Thus he points out that on heating to boiling an aqueous solution of 
the fungus which has the power of deeply bluing a tincture of guaia- 
cum, the solution not only loses this power, but was also found to 
lose the power of ever again becoming an oxygen-exciter or carrier, 
no matter how long it was kept in contact with atmospheric air. 
Finally he goes on to say that these substances which have the power 
of bringing into activity the inactive oxygen of the air must play an 
important role in the oxidation processes of vegetable materials, and 
that it is not an unwarrantable supposition that in the animal world 
as well there exist substances capable of ozonizing atmospheric oxy- 
gen at ordinary temperatures, thereby promoting the oxidation of 
other animal substances, and in a later article ( 380, 38e ) on the conduct 
of oil of bitter almonds to oxygen, in which he proved that this com- 
pound belongs to the class of ozonizing substances, he says that new 
