SEPTEMBER 15, 1899. ] 
quired the necessary skill and had disregarded 
necessary precautions for the treatment of such 
a delicate substance as diastase. In the third 
place Green gives a detailed account of Loew’s 
method for the preparation of diastase which is 
totally erroneous, since neither calcium salts 
nor caustic soda nor acetic acid mentioned in 
that description has ever been used in this 
method. Further, the diastase was not ob- 
tained from the precipitate produced by basic 
lead acetate, as Green states, but from the fil- 
trate of that precipitate. ‘Those readers who 
wish to compare the method in question with 
Green’s remarkable translation are kindly re- 
ferred to Pfliger’s Archiv, Vol. 27, p. 206. 
Another erroneous statement is found on 
page 118. We read there: ‘‘Invertase has 
been described by Atkinson and by Kellner, 
Mori and Nagaoka as existing in rice and in 
Koji, a peculiar preparation of that cereal which 
is much used by the Chinese in the preparation 
of fermented liquids.’’ The statement that the 
authors noted had found invertase in vice is 
incorrect. They have found it in Koji, which 
consists of a growth of Aspergillus oryze on boiled 
rice, and, as these authors have proved, it is 
that fungus which contains the invertase, and 
not the rice in which this enzyme could hardly 
have been suspected. Further, it might be 
mentioned that the Japanese make relatively 
as much use of Kojias the Chinese. 
As to the names adopted for new enzymes it 
may be mentioned that in Chapter IX. the 
name glucase is used for the enzyme which splits 
maltose into two molecules of glucose. Various 
chemists, however, have agreed that for the 
sake of uniformity the new enzymes should be 
named after the compound acted upon and not 
after the compounds resulting from this action. 
Consequently, the name maltase and not glucase 
is now in universal use with physiological 
chemists, which name, however, is only once 
mentioned in parenthesis in Green’s book. In 
the chapter on the oxidizing enzymes we find 
detailed accounts of various investigations on 
lacease, tyrosinase, oenoxidase and animal oxi- 
dases. One very essential point, however, has 
been overlooked by Green, namely the distinc- 
tion between oxidases and peroxidases, the for- 
mer yielding directly a blue color with dilute 
“SCIENCE. 
375 
guaiac tincture*in presence of air, the latter only 
in presence of hydrogen peroxide. The former 
are, therefore, to be considered as the more pow- 
erful, since the rather indifferent oxygen of the 
air can be brought into action by them, while the 
peroxidases want, at least in their action upon 
guaiaconic acid and some other compounds, 
—oxygen in statu nascendi, i. e., oxygen in a 
state of motion or charged with kinetic chem- 
icalenergy. That hydrogen peroxides is gen- 
erally decomposed by enzymes with liberation of 
oxygen is known and this oxygen in statu nas- 
cendi is more powerful than the common oxygen 
of the air. 
In the very ably treated chapter on the se- 
cretion of enzymes we miss the investigations 
of Bruno Hofer, who was the first who demon- 
strated the direct connection of the nucleus 
with the formation of the enzymes. 
On page 870 an erroneous conception is as- 
cribed to Niageli. He never entertained the 
opinion that the chemical powers of the enzymes 
are essentially different from those of the fer- 
menting organisms. He supposed also in the 
enzymes certain motions (although less ener- 
getic ones) to be the cause of their actions, and 
defended this view against Kunkel.f The 
quoting of Fischer by Green is entirely unjusti- 
fiable in this connection. 
In the interest of a future edition of Green’s 
book, which would gain by a little less bias we 
mention the following typographical errors : 
On page 49, line 32 for Griiber, read Gruber. 
BG 08 Sirf) SAB OO" (Cava “* Gans. 
“eo oe 100, iad 99 ce ce ce “ 
te te 1138, ‘ 22 © Nagaoko ‘* Nagaoka. 
cote 973), “17S Mallevre ‘ Mallvére: 
cc «988, ‘* 28 ‘‘Schmiedeburg read Schmie- 
deberg. 
On page 340, line 15 for Pfluger read Pfltiger. 
wc «177, ~‘* 37‘ Loew’s method read Wurtz’s 
method. 
Notwithstanding some unjustifiable remarks 
and some erroneous chemical statements, the 
* Guaiac tincture is a very valuable reagent in the 
hands of a cautious chemist who discriminates and 
controls. It is unreliable only in the hands of un- 
trained persons. Above all, it has to be frequently 
renewed and to be kept cool in the dark. 
+ Sitzungsberichte der Bayrischen Akademie der 
Wissenschaften, 1880, p. 385. 
