6 
this change. If, however, to the mixture of hydrogen peroxide and 
tincture of guaiacum one adds a small amount of platinum black, 
the mixture at once develops a blue color, for the reason that, accord- 
ing to Schoenbein, the antozone of the hydrogen peroxide is converted 
into ozone or an ozonid through the action of the platinum, and this 
at once blues the guaiacum in the manner alread}" described. He 
observed, further, that certain organic substances act upon the mix- 
ture of hydrogen peroxide and guaiacum in precisely the same way 
as platinum black. This action is shown b}" blood corpuscles and 
the gluten of wheat in a remarkable manner. In describing these 
experiments he goes on to say that if one separates the blood cor- 
puscles as completeh’ as possible from fibrin and serum and dissolves 
them in water one obtains a strong red solution. If one now adds 
a small amount of such a solution to hydrogen peroxide containing 
guaiacum it causes the mixture to take on a deep blue color after a 
few seconds, and this property of blood is not influenced b}" drying 
or boiling. That the red blood corpuscles and flour do not blue 
guaiacum alone needs scarcely to be mentioned. Animal albumin, 
fibrin, and casein are without action on the mixture of hydrogen 
peroxide and guaiacum tincture, and creatinin acts only slowl 3 \ He 
then showed that a mixture of guaiacum tincture containing a few 
drops of strongl}^ ozonized oil of turpentine is colored a deep blue 
after a few seconds b}^ platinum black and also by a solution of blood 
corpuscles. So, in the same way, ozonized ether, which alone does 
not blue guaiacum tincture, does so with the help of platinum black 
or blood corpuscles. He also observed that an indigo solution con- 
taining hydrogen peroxide, which, alone, required six hours for its 
bleaching, was bleached under the influence of blood corpuscles in a 
few seconds, and also that a mixture of indigo tincture and ozonized 
turpentine was bleached by blood corpuscles. He also pointed out 
that blood corpuscles instantly effect the liberation of iodine with the 
formation of the blue iodide of starch in solutions containing potassium 
iodide, starch, and hydrogen peroxide. It is evident from these facts 
that certain materials act upon ox}^gen and certain oxygen com- 
pounds (antozonids) in such a way as to convert the ox 3 ^gen into an 
active form and thereby oxidize many substances which neither ordi- 
nary oxygen nor the antozonids can attack. 
In a second communication (150) on this subject, Schoenbein calls 
attention to the fact that ferrous sulfate acts toward guaiacum and 
hydrogen peroxide or any antozonid, in precisely the same way as a 
dilute solution of blood corpuscles ; and in this connection his colleague. 
Hiss, showed that the chemical activity of red blood corpuscles in this 
regard is proportional to the amount of iron which they contain. He 
therefore concluded that blood corpuscles owe their power to increase 
the chemical activity of oxygen to the iron which they contain, and 
