6 
lose their power of rendering oxygen active, either through heating to 
boiling, or as the result of partial putrefaction. This would seem to 
indicate, as pointed out by Schonbein, that their power to render 
active the oxygen of hydrogen peroxide depends less on their organi- 
zation as living cells than on their iron content. 
Schonbein a made the further interesting observations that dried 
blood corpuscles are more active than fresh in the production of guaia- 
cum blue from a mixture of guaiacum and hydrogen peroxide, and 
that hydrocyanic acid retards these oxidations in much the same way 
that it hinders alcoholic fermentation and the sprouting of seeds. He 
arrived at the conclusion, therefore, that hydrocyanic acid kills ani- 
mals so rapidly for the reason that it hinders catalysis and interferes 
with respiration. 
Aside from their general interest the chief importance attaching to 
these earlier observations of Schonbein is that these reactions afforded 
delicate tests both for hydrogen peroxide and blood: and of the various 
tests for blood 6 that have been proposed from time to time, certainly 
the greater number, if not all, depend on the production of some 
colored substance, as the result of the oxidation of a chromogenic sub- 
stance by hydrogen peroxide and blood. 
During recent vears. however, the oxidizing ferments of the blood 
have been the subject of further investigations. Lumiere and Chev- 
rotier,- for example, have prepared a protoplasmic extract of red cor- 
puscles by vigorously centrifugalizing a mixture of blood and isotonic 
liquid, collecting the corpuscles, and washing several times with the iso- 
tonic liquid. The washed corpuscles were then subjected to alternate 
freezing and thawing in order to disintegrate them, and the mixture 
eentrifugalized. The liquid was then filtered and rendered isotonic 
by means of sodium chloride. It was again filtered and preserved in 
sterilized flasks. This liquid, which the authors have called haemoplase, 
rapidly loses oxygen in vacuum, becoming violet black in color, the 
red color being restored bv agitation with air. It was found bv these 
observers to possess the properties of an oxidase to a very marked 
degree. 
Quite recently, Jolles and Oppenheim ' 7 have made a quantitative 
study of the power of the blood of man and certain of the lower ani- 
mals to decompose hydrogen peroxide. It has been found as the result 
of these investigations, that the blood of amphibious animals decom- 
poses hydrogen peroxide very slowly as compared with the rate of 
« Bericht iiber die Verhandlungen der Vaturforschenden Gesellschait in Basel, 
IV, 410 and 767. 
&Schaer, Zeit. f. anal. Chem., 1903, p. 1; and Archiv.der Pharmacie, 238 (1900), 
42-48. 
c Compt. rend., 141 (1905), 142-143. 
( i Zeit. f. anal. Chem., 44 (1904), l-5pand Munch. Med. Woch., 51, 20S3-20S5; and 
also Virchow’s Archiv (1905 ), ISO, 1S5 and 225. 
