OcTOBER 30, 1902] 
NATURE 
651 
a few errors have unfortunately remained uncorrected. 
These he has noted on p. xvi.” 
One or two have still escaped the author’s notice. 
Muscat is ordinarily spelt by him “ Maskat,” but once 
“Mascat ” appears ; and no regular rule is followed with 
regard to the hyphening of Arabic compound names; thus 
we have “ Roba-el-Khali” (p. 73), but “ Wadi er Rumma” 
(p. 71), which is spelt “ Wadi-er-Rumma” in the index. 
So in other cases. The correct form, of course, is 
Roba el-Khali, Wadi er-Rumma ; only one hyphen ‘is 
necessary. 
We are at one with Mr. Hogarth as to the unde- 
sirableness of too pedantically accurate a transcription 
of Oriental names, but it seems to us that “ Hadramut” 
and “Riad” would be better replaced by Hadhramut 
and Riadh, which we can pronounce even if the Germans 
cannot. And though Mr. Hogarth defies the pedant with 
his “ Bedawins,” we are unable to back him up in his de- 
fiance ; “ Bedouins” or “ Beduins ” may be all very well, 
but not “ Bedawins” ; either “‘ Beduins” or “ Bedawin,” 
one or the other. 
In the maps there are one or two mistakes which need 
correction ; for instance, in Fig. 36, “Yidda.” In Fig. 
16 the railway is made to cross the Nile immediately 
south of Siut, which is itself placed much too far south. 
In reality the railway crosses further south than in the 
map, at the Nag’ Hamadi bend. South of Aswan, spelt 
here and in other maps “ Assuan,” the railway gets wrong 
again. There is no line between Shellal and Wadi 
Halfa, and there zs a line along the Nile bank south of 
Wadi Halfa, which runs as far as the Third Cataract, to 
Kerma. In Fig. 49 the Athens-Kephisia-Lavrion line 
is not inserted at all, nor is the new Athenian “‘ under- 
ground” from the Theseion v7é Monasterdki to the 
Omonoias. It is true that these are only sketch- 
maps, but if the railways are inserted in them at all, 
they should be inserted correctly. In the fine ethno- 
graphical map opposite p. 176, we do not quite like 
the unhesitating colouring of Egypt with the Semitic 
yellow ; there should be some brown or other coloured 
stripes across it. Nor do we think that pure brown 
should begin with the Wadi Hammamat; Nuba is not 
spoken north of Daraw, south of the 25th parallel, so the 
line should run north-eastward from Dardw to Kusér. 
Should there not also be some Magyar, Szekler and 
Teutonic stripes and spots in the portion of Hungary and 
Siebenbiirgen which comes into the upper left-hand 
corner of this map and is entirely coloured with Rumanian 
purple? 
these parts at all, but if they are coloured in the map, the 
coloration should be correct. 
For these cartographical slips Mr. Hogarth, of course, 
cannot be held entirely responsible. We point them 
out merely that they may be corrected in the second | 
edition. They in no way detract from the value of the 
maps as a whole. 
One thing we regret, the absence of photographs. A 
few pictures of salient features of the land—a Greek isle, 
a desert wadi, a Cilician gorge—would have added greatly 
to the interest of the book. 
We welcome Mr. Hogarth’s work, then, not only as a 
notable contribution to geographical literature, but as a 
book which will—as is the idea of the series—appeal to a 
NO. 1722, VOL. 66] 
It is true that the book does not deal with | 
| larger public than the members of scientific societies, 
| and will probably not only cause its general readers to 
take an unwonted interest in geography, but will also 
direct their attention to threatening political questions 
for which sooner or later they will be called upon to help 
to devise a solution. H. H. 
CHEMISTRY AND LIFE. 
Das Eisen als das thatige Prinzip der Enzyme und der 
lebendigen Substanz. Von N. Sacharoff. Pp. 83. 
(Jena: G. Fischer, 1902.) Price M. 2.50. 
HIS philosophical treatise, originally written in 
Russian, is presented to us in a translation by 
Dr. Rechtsamer. Without going so far as to say it is of 
the first importance, it may be safely affirmed that it will 
be welcomed by physiologists as a contribution to the 
discussion of the more obscure chemical processes con- 
nected with the life of the protoplasm. The author at 
the outset reviews the different hypotheses that have 
been advanced as to the intimate constitution of living 
matter, and finds them all unsatisfactory. He holds 
that the behaviour of protoplasm cannot be attributed 
to either its organisation, or its chemical composition or 
structure, and suggests that all the vital processes must 
be regarded as arising from a decomposition or splitting 
of the living substance in consequence of the access of 
oxygen, followed by a series of recombinations. Hence 
he turns to a study of the nature of this auto-decompo- 
sition with a view ‘to determining its cause. 
Proceeding to the action of oxygen in the animal 
and vegetable cell, and seeking for something universally 
present therein which is capable of easy oxidation, and 
of yielding compounds which can be reduced again or 
further decomposed with comparative ease, he considers 
he has found it in minute traces of iron. He puts forward 
accordingly a hypothesis of his own, to the effect that 
the various vital phenomena of protoplasm are set up by 
the oxidation of a minute trace of iron contained in 
the living substance, with subsequent or concurrent 
hydrolysis. 
This theory is examined at some considerable length 
in the subsequent chapters, attention being given first to 
enzyme action, which he takes as one of the most remark- 
able of the metabolic processes. His views on this 
point will not commend themselves to all physiologists, 
but he argues in favour of them with some skill. After 
reviewing the theories of enzyme action advanced by 
Liebig, Nageli, Berzelius, Wiirtz and more recent writers, 
| and quoting published experimental evidence of the action 
of several of these bodies, he suggests that the active 
principle of enzymes is a substance which is capable of 
auto-oxidation and auto-reduction, and that the working 
which they exhibit depends upon alternate oxidation and 
reduction of this active principle. An experiment of his 
own with papain may be quoted in illustration of his 
| view. He prepared a solution containing 2 per cent. of 
| papain and heated it to boiling. Taking another solution 
| of the same enzyme, containing Io per cent., he prepared 
three tubes. No. 1 contained two drops of this active 
| extract and 10 c.c. of the boiled extract; No. 2 two 
drops of the active extract with 10 c.c. of water; No. 3 
10 c,.c. of the boiled extract alone. He added to each a 
