Marcu 12, 1914] 
NATURE 
39 
classified with an index number on the decimal system. 
The division of the Antarctic into four equal quadrants 
is a mistake, as it results in the partition of the Ross 
Sea, but any scheme of division must have its draw- 
backs, especially as the isolated known areas become 
linked by further exploration. M. Denucé has founded 
his work en the polar ‘library which the commission 
is trying to form in Brussels, but he has gone far 
beyond the scope of that collection, and has spread 
his net wide enough to include various important 
reviews of Antarctic works, many newspaper articles, 
and notes in geographical publications, some of which 
inevitably would be lost sight of but for a careful com- 
pilation of this kind. On the other hand, there is 
room for revision and additions. . We have noted a few 
omissions, and some slight errors in references, besides 
the premature inclusion of some papers announced, but 
‘not yet published. However, M. Denucé’s work 
a welcome supplement to Dr. H. R. Mill’s_ biblio- 
graphy in the ‘Antarctic Manual” of 1901. 
is 
THE symbol |x| as applied to real quantities denotes 
the numerical value of x irrespective of algebraic sign. 
In a recent paper (Moscow: I. N. Kouchnéreff and 
€o., 1913), Dr. D. Riabouchinsky, director of .the 
aerodynamic institute of Koutchino, treats this quan- 
tity as a junction of the variable x, and shows how 
this method leads to interesting formula invoiving 
the solution of equations, differentiation, and integra- 
tion. A number of elegant geometrical applications 
are also given, such as equations of broken lines, and 
equations of limited portions of planes, such as a 
square area. 
Tue first number of the Washington University 
NSiudies contains an interesting paper by Mr. Benjamin 
M. Duggar on Lycopersicin, the red pigment of the 
tomato, and the effects of conditions on its develop- 
ment. This red pigment is partially or completely 
suppressed when green fruits are. ripened at a tem- 
perature of 30° C. or above, the inhibition of redden- 
ing being proportional to the temperature above this 
point. The factors for reddening are not destroyed 
by high temperatures, and a return of the fruit to 
normal conditions causes rapid pigmentation. The 
presence of oxygen is necessary to bring about redden- 
ing, and fruits maintained in an oxygen-free atmo- 
sphere fail to redden at the normal ripening tempera- 
ture. The colouring matter of the red peppers and of 
the arils of Momordica exhibit the absorption bands 
of Lycopersicin. 
Tue Photographic Journal for February contains a 
condensed account prepared by Mr. F. F. Renwick of 
Dr. H. Ewest’s thesis on quantitative spectrophoto- 
graphy. After giving a short account of most of the 
methods used previously, the author gives a descrip- 
tion of his own apparatus, and the tests he has made 
in order to see that it is capable of giving trustworthy 
results. The light from a Nernst lamp is condensed 
on the slit of a direct-vision spectroscope, and the 
spectrum is produced on the photographic plate to be 
tested. Immediately in front of the plate is a neutral 
Goldberg absorbing wedge which covers the whole 
| portion of the negative then allows the character of 
| 
| 
the plate to be determined, and the relations between 
the time of exposure, the intensity of the light, and 
the density of the negative in all parts of the spectrum 
to be investigated.. The method seems convenient and 
trustworthy, and should lead to an extension of our 
knowledge in this field. 
AN important paper on the nature of enzyme action 
by Mr. Hendrik S. Barendrecht appears in the Bito- 
chemical: Journal (vol. vii., part 6). In this paper, 
which bears the title, ‘‘Enzyme Action, Facts and 
_ Theory,’ it is pointed out that the researches of the 
past few years on the kinetics of enzyme action have 
brought more confusion than clearness into this field. . 
An attempt is made by Mr. Barendrecht to clear up 
some of the contradictory statements regarding the 
kinetics of some of the most simple enzyme actions. 
As a working hypothesis it is assumed that enzyme 
action spreads like a radiation from an enzyme par- 
ticle as centre; this conception is developed mathe- 
matically for the cases of more or less concentrated 
solution of the substrate, and the effect is considered 
of the products of the action exercising an absorption 
on the active radiations, and hence cn the velocity of 
the change. In this way velocity equations are de- 
rived, which explain certain cases which have appeared 
be abnormal. In particular the special cases of 
the action of invertase on cane sugar, of lactase on 
milk sugar, and of maltase on maltose are considered, 
with especial reference to the effect of the resulting 
sugars on the velocity constants. 
to 
In the course of an interesting and suggestive pape 
on the calculations and details for steel-frame build- 
ings, read at the Concrete Institute on February 26, 
Mr. W. Cyril Cocking urged that all constructional 
engineers and draughtsmen should support the London 
Building Acts 1909 Amendment. It may be thought 
by some that certain amendments to the Act would be 
desirable, but no concessions can be expected unless 
all concerned with its working combine to make the 
best of it as at present framed. Time has shown 
already that the Act has been the means of improving 
considerably the general design of steelwork. The 
rg09 amendment is an Engineer’s Act essentially, and 
the reinforced concrete regulations will be more so, 
| and it seems within the possibilities of the near future 
plate, and is raised with the plate at a uniform rate. | 
The curve separating the opaque from the transparent 
NO. 2315, VOL. 93] 
that, provided the engineer takes advantage of his 
opportunities, he might assume the more important 
position—the architect then confining his attention 
solely to the architectural treatment. Whole-hearted 
cooperation between engineer and architect will tend 
to provide London with buildings in which the archi- 
tecture is more fully developed, and combined with 
sound construction in such a manner that the demands 
of economy and scientific utility are satisfied fully. 
A GENERAL discussion on every aspect of the passivity 
of metals was held at the meeting of the Faraday 
| Society on November 12 last, and was reported in 
the issue of Nature for November 20, 1913 (vol. xcii., 
p. 350). The eight papers read on that occasion, 
together with the discussion upon them, have now 
been reprinted from the Transactions of the Faraday 
Society in book form, and can be obtained at the 
* price of 7s. 6d. 
