14 
Tarugi (183), on the other hand, is of the opinion that the reaction 
is accomplished by the hemoglobin, and that the sulphur in this com- 
pound is first converted into Caro’s acid by the action of the hydrogen 
peroxide or ozonized oil of turpentine, and that it is this acid which 
accomplishes the bluing of the guaiacum. 
According to Liebermann (103) the peroxide contained in old oil 
of turpentine first gives up its oxygen to the hemoglobin, forming a 
compound of hemoglobin rich in oxygen, probably a peroxide of hem- 
oglobin, and that the oxygen of this compound is appropriated by the 
guaiacum with the formation of guaiacum blue, and that methemo- 
globin is also a carrier of oxygen. 
The whole subject of induced oxidations by means of hydrogen 
peroxide has been extensively studied by Loevenhart and Kastle 
(107), and in the second part of their article on this subject the view 
has been advanced that irrespective of the composition of the carrier 
the latter acts by first combining with the hydrogen peroxide to form 
complex unstable holoxide or moloxide derivatives, which give up 
their oxygen to the reducing substances more easily than does the 
hydrogen peroxide itself. This theory of oxygen-carr^^ing is in har- 
mony with the more recent work of Kastle (79) on the subject of per- 
oxidase accelerators. According to this hypothesis, therefore, the 
function of blood as an oxygen carrier in reactions of the Schoenhein- 
Van Deen type could probably be explained most simply and easily 
on the supposition that the iron-containing blood pigment combines 
with the peroxide to form a moloxide derivative, wliich in turn easily 
gives up the whole or a part of its oxygen to the chromogenic sub- 
stance with the production of a dye of characteristic color. Thus if 
the carrier in blood be represented by B and the chromogenic sub- 
stance by Chr, we would have — 
and 
B.H,0,+ (Jhr = B+ 
or 
2^.H202+ Chr = B + ClirO^, 
or to take the specific case of phenolphthalm, in which the precise 
nature of the oxidation product, phenolphthalein, is known, we 
would have — 
B -f H 2 O 2 = i?.H202, 
and 
5.H2O2 + C2oHj6^4 = B 2H2O + C2oH^404. 
This, of course, presupposes that the carrier is a perfect carrier, and 
that therefore it is completely regenerated at the end of any complete 
cycle of the reaction. If it is not thus completely regenerated in 
