JUNE 13, 1912] 
NATURE 
Os 
of 
conduct and extend that industry, and no such 
literature can prove of greater interest to those 
specially concerned with its modern development, 
or the large number of men of science outside its | 
particular sphere, than that of explosives. 
The names of those discoverers and early 
workers in connection with fulminate of mercury, 
guncotton, nitroglycerine, &c., are familiar to all, 
but few probably realise the risks encountered, 
the difficulties to be overcome, and the patience 
and perseverance exhibited in overcoming those 
difficulties. The thorough and exhaustive manner 
in which Abel and his colleagues investigated the 
problems of the manufacture, decomposition, and 
safe storage of guncotton, leading to the publica- 
tion of that marvellously complete series of 
memoirs by Abel in 1866-67, has seldom been 
equalled, and ten of these are given in sufficiently 
extensive form in the present volume. In view 
of the now well-recognised catalytic effect which 
the products of decomposition of guncotton exer- | 
cise in promoting further decomposition, the ex- 
periments of Abel in submitting stable guncotton 
to the action of the fumes from an unstable 
sample are of particular interest, as are also his 
experiments of the effect of moisture on the k-ep- 
ing qualities, especially when the moist material 
is exposed to the action of sunlight. 
most fundamental of Abel’s discoveries was that 
decomposition appeared to be due to foreign 
matter i the original cellulose, which, on nitro- 
genising, yielded unstable products. 
The work of Nobel, again, in connection with 
nitroglycerine and its application is another ex- 
ample of perseverance, ingenuity, and inventive 
genius, but here Mr. MacDonald has been some- 
what sparing, for only four pages are devoted to | 
his labours. 
Of great interest are the early communications 
of Pelouze and Schénbein relating to their rival 
claims as the discoverer of guncotton. Pelouze 
(1838), in extending Braconnot’s work on nitro- 
starch, which he indicated might be applicable to 
artillery, also noted that paper, cotton, and linen 
were nitrated, their new properties being ascribed 
to xyloidine (nitro-starch) which covered their 
Schénbein’s first nitration (1845) ap- 
pears to have been on sugar, but soon after the 
other nitro-substances of like character, including 
guncotton, were prepared. Schénbein no sooner 
realised the possible value of the latter than he 
instituted trials in pistols, carbines, and cannon. 
Whilst Pelouze therefore nitrated cotton prior to 
Schénbein, he undoubtedly thought it the same 
body as from starch and does not appear to have 
pursued the matter. Schénbein realised their 
essentially different character, but it remained for 
NO. 2224, VOL. 89| 
surfaces. 
One of the | 
| Crum of Glasgow to demonstrate the different 
| composition of the two bodies, and his original 
paper (1847) is of great interest. 
| Mr. MacDonald’s collection of memoirs covers 
| fully the development of guncotton both in 
England and on the Continent, and many are the 
interesting points the reader will find, among them 
a communication from Berzelius to Schénbein, and 
the correspondence between the latter and Mr. 
Hall after the terrible disaster at the Faversham 
works in July, 1847. 
From the few points mentioned it will be seen 
that Mr. MacDonald’s collection of these papers, 
which first appeared in “Arms and Explosives,” 
is particularly welcome, and one may hope that 
similar reprints or condensations of papers of 
great historical interest may, from time to time, 
become available to the student of to-day, for they 
would form an excellent course of post-graduate 
reading. i; SsSaeBe 
PROGRESS OF SCIENCE. 
Fortschritte der naturwissenschaftlichen For- 
schung. Herausgegeben von Prof. E. Abder- 
| halden. Dritter Band. Pp. iv+352. Price 
| 16 marks. Vierter Band. Pp. iii+300. Price 
| 15 marks. (Berlin and Vienna: Urban and 
Schwarzenberg, 191r and 1912.) 
HESE further volumes of a valuable work 
are quite up to the level of the preceding 
ones. There is, however, a considerable reduc- 
tion in the number of the separate essays, and 
while this enables the writers to deal with their 
| subjects at greater length, it somewhat narrows 
the range. In vol. iii., A. Wegener deals with 
recent investigations in atmospheric physics, in- 
cluding the stratification of the atmosphere, 
the isothermal layer, the formation of air-billows, 
the structure of hail and thunder clouds, and 
Birkeland and Stérmer’s electronic theory of the 
| aurora. The article is lavishly illustrated by 
photographs and diagrams. W. Johansen, of 
Copenhagen, deals with heredity on the principle 
of the genotype, i.e. the aggregate of inherited 
tendencies embodied in the germ. His main 
thesis is to show that genotypes differ discon- 
tinuously, and thus recall the discontinui- 
ties between chemical species. Dr. Gustav 
Eichhorn, of Ziirich, has an essay on the present 
position of wireless telegraphy and telephony. 
The system chiefly dealt with is the Telefunken 
system. As regards telephony, we find an in- 
teresting account of the comparative merits of 
Duddell, Poulsen, and Goldschmidt’s recently 
invented high-frequency generator. 
There is a lengthy article on directive forces in 
| plant geography by M. Rikli, of Ztirich. He goes 
