Tee 
Aug. 17, 1871] 
‘members of the Academy. 

causing great apprehension as to the safety of the Italian 
observatory of Vesuvius, The lava has already partially sub- 
merged the hill of the Canteroni on which the observatory 
stands, and the immediate erection of a strong dyke of scoria so 
as to divert the stream of Java is urgently asked for. 
WE are requested to state that the terrible earthquake at 
Bathang in China, of which we lately published an account 
(NATURE, vol. iv. p. 45), occurred on April 11, 1870, and not 
this year, as might be inferred from the description. 
THE American Polar Expedition in the steamer Polaris 
(Capt. Hall) left Brooklyn on June 29th. Dr. E. Bessels, of 
Heidelberg, who was Scientific Director of the German Expedi- 
tion to Nova Zembla in 1869, is appointed to the same position 
on this expedition. The vessel is provisioned and equipped for 
two-and-a-half years’ absence, but the explorations may be con- 
tinued longer it Capt. Hall desires it, and fresh supplies will be 
sent. The expedition is undertaken principally for geographical 
discovery, but every opportunity will be made use of to make 
scientific observations and experiments, for which purpose a long 
series of instructions have been drawn up by a committee of 
These consist of Prof. Henry on 
meteorology ;' Prof. Newcomb on astronomy ; Prof. Higlard on 
magnetism ; Prof. Baird on natural history; Prof. Meek on 
geology; Prof. Agassiz on glaciers. Orders have been given that 
small copper cylinders containing letters, scientific intelligence, 
&c., shall be frequently thrown overboard during the progress of 
the expedition, and these, when found, are to be sent to the 
Navy Office and afterwards published. 
A MOST important discovery is announced from the Isthmus 
of Panama. In the district between Aspinwall and Panama, 
and extending over a large area, valuable beds of coal have been 
discovered and recently fully explored. The quality of the coal 
has been tested and most favourably reported on, These mines 
can be worked to great advantage, and the seams are rich and 
extensive, and there is ample water communication to the coast 
by means of the river Indis. If further investigations confirm 
this preliminary report, great benefit cannot fail to result to 
commerce in the Atlantic and Pacific Oceans from this opportune 
discovery. 


THE GUN-COTTON EXPLOSION AT 
STOWMARKET 
an HE disastrous explosion of gun-cotton, which occurred 
on Friday last on the premises of the Patent Safety 
Gun-cotton Company, is a calamity of unusual significance. 
Besides the large number of killed, amounting, we believe, 
to five-and-twenty persons in all, there were as many as 
seventy maimed and injured, many of them too, in such a 
manner as only violent explosions are known to torture and 
lacerate their victims ; and when it is taken into consi- 
deration that in all probability a dozen tons of the material 
actually exploded, the grave nature of the accident is in 
truth not surprising. The whole group of factory-build- 
ings and out-houses were levelled to the earth at one fell 
swoop, and for miles away the effect of the catastrophe 
was acutely felt. 
But it is not only from a social point of view that the 
affair is to be deplored. As a result seriously affecting 
the science of explosives, the occurrence is peculiarly un- 
‘fortunate ; for the belief in the safety of gun-cotton as an 
industrial and military agent will now be gravely shaken. 
It is all very well for scientific men to adduce a plausible 
reason for the occurrence, and to prove conclusively that 
with due care and precaution a disaster of this nature 
could not possibly have happened ; but the public unfor- 
tunately will not be satisfied with a theoretical assurance 
_ of this kind ; and indeed measures should certainly be 
taken, not only to guard against such wholesale death and 
destruction, but to render the same absolutely impossible. 
WVATURE . 



309 

The true cause of the disaster we can scarcely hope to 
discover ; but, leaving out of consideration any personal 
carelessness on the part of the workmen, the ignition of 
the cotton must either have occurred through the acci- 
dental firing of a cartridge, or primer, or through sponta- 
neous combustion. It is well known that pyroxilin may 
be exploded in two totally distinct ways—that is to say, 
either by inflammation or detonation. In the first instance 
the cotton, unless confined, only burns fiercely, and does 
not explode like gunpowder on the instant ; while, on the 
other hand, if it is ignited by detonation or percus- 
sion, the material acts in the same violent manner 
as nitro-glycerine or fulminate powder. Is the cata~ 
strophe at Stowmarket, then, the result of detonation, or of 
the milder form of explosion, such as inflamed gun-cotton 
confined in lightly-built magazines would produce? If 
sporting cartridges, such as contain a small charge of ful- 
minate or detonating primers, were at all near the spot, 
the culpability of the authorities is very great indeed ; for 
the approximation of the two agents constitutes obviously 
a source of extreme danger, and it is really hard to believe 
that so thoughtless'a proceeding could have been possible. 
At the same time, if a detonation actually did take place, 
as in fact some of the results would lead us to believe, 
then there is no other way of explaining the occurrence. 
In regard to the theory of spontaneous combustion, 
we must not be too eager to draw conclusions, as the 
careful experiments recently made by Prof. Abel distinctly 
prove that decomposition in this wise is almost impossible, 
provided the pyroxilin has been carefully manufactured, 
Truly, if such has not been the case, and there existed 
impurities or imperfectly converted masses in the store of 
gun-cotton at Stowmarket, then a valid reason for the 
explosion is no doubt at hand. Still it must be remem- 
bered that pyroxilin only takes fire ata high temperature 
(300° or 350° F.), and therefore we must suppose that not 
only was the recent hot sun allowed to shine uninter- 
ruptedly upon the magazines, but that the latter were, 
moreover, very badly ventilated, and altogether ill cared 
for. Again, to have produced such wide-spread devas- 
tation, the stores or outbuildings containing the cotton 
must have been somewhat strongly and firmly built, other- 
wise there would have been no resistance to the burning 
mass, and consequently no violent explosion, for it must 
be borne in mind that the more completely the charge is 
confined, the more energetic will be the result. 
Under any circumstances, then, we must come to the 
conclusion that either the gun-cotton was strongly con- 
fined in cases or magazines and simply inflamed, or that 
the material was detonated by a charge of fulminate 
powder ; and in whichever way the accident fappened, 
the same was in great measure due to neglect and care- 
lessness. Why, indeed, sucha large store of dry gun- 
cotton should have been kept so near a populous factory 
itis hard to understand ; and inasmuch as the compound 
is always prepared in a wet, and, consequently, harmless 
condition, it would appear that the desiccation of the 
mass is afterwards carried on in close proximity to the 
less dangerous departments of the works. It is truly 
lamentable that, after the prolonged rescerches of Schon- 
bein, Abel, Brown, and others, the information and par- 
ticulars brought to light should not have been more ap- 
preciated and made use of by those so directly interested 
in the matter ; for one cannot help thinking that if the 
business of the Stowmarket Company had been carried 
on under competent scientific supervision, we should not 
now have to lament so deplorable an accident. 
While then we must all deeply regret this sad occurrence 
itis to be hoped that the favourable judgment passed 
upon gun-cotton by scientific men during the last ten 
years will not be completely ignored ; but that, on the 
contrary, a proper use may be made of the valuable in- 
fcrmation at our disposal by employing it in the framing 
of regulations to govern more strictly and efficiently the 
manufacture of explosives. | year. 
