108 
an important communication on the quantitative con- 
version of cellulose into dextrose by means of cold, 
fuming hydrochloric acid of sp. gr. 1204° to 1°212°, 
containing from 4o to 414 per cent. of hydrogen 
chloride. A problem has thus been solved which for 
more than one hundred years has been vainly at- 
tempted by the use of hot mineral acids and other 
means. Although ordinary concentrated hydrochloric 
acid containing 37°6 per cent. of hydrogen chloride 
does not dissolve cellulose but merely disintegrates the 
fibre and causes gelatinisation, the more concentrated 
acid containing 4o per cent. rapidly dissolves it, and 
after twenty-four to forty-eight hours 95 to 96 per cent. 
of the theoretical quantity of dextrose is present in 
the solution. The course of the hydrolysis has been 
followed by observing the specific rotatory power and 
copper-reducing value of the solution in successive 
intervals of time. In this way it was found that the 
cellulose at first dissolves in an optically inactive 
form, thus differing entirely from starch, which gives 
a highly dextro-rotatory modification from the start. 
Only after one hour is a slight dextro-rotation to be 
observed, which progressively increases; in the early 
stages the product, which can be precipitated from 
solution by water or alcohol, is of a dextrin-like 
character, but without either reducing power or 
specific rotation. The solution gradually develops 
reducing properties as the specific rotation increases, 
but during the first six hours the amount of 
““dextrose”’ calculated from the reducing power is 
much less than that calculated ‘from the change of 
rotation. It is thus probable that a complex, optically 
active, but non-reducing sugar is formed first, and 
that this is later further resolved into dextrose. 
One of the most striking observations recorded in 
the paper is the very high specific rotation shown by 
dextrose when dissolved in concentrated hydrochloric 
acid. In 414 per cent. hydrochloric acid [a]*° was 
found to be 106°, which approximates to that of the 
so-called o-form of dextrose (110°), the ordinary value 
observed in aqueous solution for the equilibrium mix- 
ture of a and 8-forms being 52°5°. In 44’5 per cent. 
hydrochloric acid, however, the: extraordinarily high 
value of 164°6° was observed for [a],, at 5° C. 
No. 29 of Scientia contains a number of articles of 
general scientific interest. Dr. E. E. Fournier d’Albe 
writes on interstellar space, Dr. A. Findlay gives a 
short account of the phase rule and its applications, 
and Mr. Léon Fredericq contributes an interesting 
summary of the methods by which animals utilise 
chemical and physical forces as means of defence. 
Mr. E. Rignano discusses the problem of the evolution 
of reason, and G. Cardinali traces the influence of 
Hellenic culture on the development of Roman 
VarRIABLE Neput-2.—M. Borrelly’s recent announce- 
ment in the Comptes rendus that Hind’s nebula ap- 
peared to be passing through a period of maximum is 
now followed (No. 9, Comptes rendus) by a note from 
M. G. Bigourdan incorporating a list of the dates of 
published measures together with the names of the 
NATURE 
[SEPTEMBER 25, 1913 
26, 1861. Attention is directed to the importance of 
confirming M. Borrelly’s observation. 
Comer (1913b) Mercatr.—The following is the 
ephemeris of Metcalf’s comet as taken from the 
Astronomische Nachrichten, No, 4682 :— 
12h. M.T. Berlin. 
R.A. Dec. Mag. 
Der Mts. ‘5 fp 
Sept. 25 3 41 54 +76 44'2 = 
aoe... 3. 0 sObee TF 77 — 
Baas v=) (2 25) Se ewe 77 314 84 
Boe ye. 1 42538 77 16°6 - 
29 I O15 76 40°9 —_— 
BON c=. O21 1304 an 75 33°3 _ 
Oct. I a Fey eee Yess: 74. 10 8:2 
Zee 23-1020 
The above ephemeris has been calculated by Prof. 
Kobold from the observations on September 2, 6, and 
10, which gives quite a new set of parabolic elements 
and makes the places of the comet very different from 
those calculated from his previous elements. 
The present elements are as follows :— 
T=1913 Sept. 13°9168 M.T. Berlin. 
72 6°'0 _ 
or = UL7"" ean 
Q=157° 9! So rons 
; tay epee 
log g =0°133805 
As this comet is getting brighter and higher up in the 
sky, it should be observable with telescopes of small 
aperture. 
Comet 1913c (NEUJMIN).—This comet, discovered by 
Neujmin, is becoming fainter, being now nearly of the 
12th magnitude. For the sake of those who wish 
to follow it further with larger telescopes, the fol- 
lowing ephemeris by Herr M. Ebell, taken from a 
supplement to the Astronomische Nachrichten, No. 
4680, is given :— 
12h. M.T. Berlin. 
Bare (true) * Dec. (true) Mag. 
i. m. on ° ‘ 
Sept. 25 23 39 58 '+6 47 0. aoe 
a 20 23 39 35 6 188 
Eve 23 39 14 6 32°4 
» 28 23 38 54 6 45°4 
1» 29 23 38 36 6 57°9 
a 30. 23 38 19 7 10'0 
Oct. . 1 2335008 SROh ile’ 
” ay) 23°37 49 7 327 12°T 
ANNALS OF THE Bureau or Loncirupes.—Containing 
accounts of the inception, organisation, programmes, 
and transactions of two international conferences 
which have led to results of the highest practical im- 
portance in applied astronomy, the ninth volume of 
the Annals of the Bureau of Longitudes attains the dis- 
tinction of being not only a valuable document in the 
history of that science, but also of marking a stage in 
the growth of international cooperation in scientific 
work. Of the successful issue of the Congrés des 
Ephémérides, let us recall only the sixth of the seven 
general resolutions adopted, namely, that the names 
of stars should be accompanied by designations of 
their spectral type after the notations of Pickering. 
The work last autumn of the Conférence Internationale 
de Il’Heure, of course, chiefly centred around the em- 
ployment of wireless telegraphy not only in the dis- 
tribution of time, but also in the service of meteoro- 
logy. The value of these applications is attested both 
by the rapidly increasing numbers using the time- 
signals, especially on land, and by the fact .that it 
has recently been found necessary to add more than a 
dozen stations to the original six for which the 
' meteorological elements were distributed on the 
observers dating from Schénfield’s observations, July } resolution of the conference. 
NO. 2291, VOL. 92] 
OE a 
