JuLy 29, 1915] 
NATURE: 
609 


The inhalation of a very small proportion of sulphur 
dioxide gas causes coughing, four volumes — in 
10,000 of air rendering it irrespirable, but if 
the sufferer escapes from the zone within a reason- 
able period the effects pass off, and the inhalation of 
dilute ammoniacal fumes rapidly affords relief. The 
gas can be easily liquefied by cold or pressure, and 
one pound of the liquid gives roughly 5 cub. ft. of the 
gas. The liquid sulphur dioxide is being used by the 
enemy in hand-grenades, which, broken by a small 
bursting charge, scatter the contents when thrown into 
the opposition trench, when they immediately vola- 
tilise, and often contain other volatile irritant bodies 
besides the sulphur dioxide. 
Chlorine, which in all probability is the gas which 
has been used to the greatest extent, is of a yellowish- 
green colour. It can be liquefied under a pressure of 
six atmospheres, and has an insupportable odour. 
When inhaled even in minute quantities it causes great 
irritation of the mucous lining of the throat and lungs, 
air containing from 2 per cent. of it rapidly proving 
fatal. This gas can be made with the greatest ease 
by heating a mixture of hydrochloric acid and black 
oxide of manganese, but it is now produced in large 
quantities in certain electrolytic processes, from which 
it can be collected and liquefied, the liquid being stored 
in lead-lined steel cylinders closed by a valve. 
In such a cylinder the gas above the liquid exercises 
a pressure of at least 90 lbs. on the square inch, so 
that if a cylinder containing it be fitted with a tube 
which passes down into the liquid and is provided at 
its exit from the cylinder with a valve, on opening 
the valve the liquid is blown out in the form of a 
spray, which at atmospheric pressure instantly assumes 
the gaseous form, and it is in this way that it has 
been chiefly used. It is reported, however, that where 
the German trenches are of a more or less permanent 
character, broad tubes with valves at intervals are laid 
a few feet in front of the trenches with the openings 
pointed towards the Allies, the trunk tubes being 
connected with a gasholder and chlorine plant situated 
in a sheltered spot some little distance away, so that 
the mere opening of the valves sets free a flood of gas 
without the disturbing influence of the cooling effect 
produced when gas is liberated from a cylinder of*com- 
pressed liquid. The yellow colour of the gas employed 
has been a marked feature of all the more serious gas 
attacks, but it must be remembered that either chlorine 
or nitrogen tetroxide would give very much this effect, 
although the latter would be browner in colour. 
Nitrogen tetroxide constitutes the fumes formed 
during the action of nitric acid on various substances 
in contact with air, and can be liquefied at tempera- 
tures below 26° C. to a liquid varying in colour with 
the temperature. Most observers from the front 
insist that this gas has been largely used, but 
this seems doubtful, as nitric acid and _ the 
oxides of nitrogen play so important a part 
in the manufacture of explosives that in spite of the 
large quantities of nitric acid made by electrical pro- 
cesses from atmospheric nitrogen, the enemy cannot 
spare much for this purpose, more especially as 
chlorine is more effective and wickedly cruel in its 
action, and can be obtained in any desired quantity 
without affecting the supply of any other munitions 
of war. 
Only two liquid elements are known, mercury and 
bromine, and the latter, which is closely allied to 
chlorine in all its properties, becomes a vapour at 
atmospheric temperatures, and boils at 59° C. Ger- 
many produces practically the whole European supply 
from traces of magnesium bromide found in the great 
salt mines.at Stassfurt. It is a reddish-brown liquid, 
and gives a vapour of the same colour, which violently 
NO. 2387, VOL. 95| 
‘attacks the eyes 

as well as the mucous lining of the 
nose, throat, and lungs. Its effect upon the system is 
the same as that of chlorine, and it is supposed to 
have been used by the Germans in asphyxiating shells, 
the bursting of which would scatter the liquid bromine 
and facilitate its conversion into vapour, which owing 
to its great weight would sink to the ground. 
A form of poisoning used by the enemy has been 
the use of amorphous phosphorus in the shrapnel 
shells used partly for the marking of ranges. Amor- 
phous phosphorus is a violet-brown powder, largely 
used in the composition on safety-match boxes, and 
differs widely from yellow phosphorus in that it is non- 
poisonous, and inflammable only at a temperature that 
converts it into the inflammable yellow form. A small 
cartridge of this included in the 18-pounder shell is 
converted by the heat of explosion into the ordinary 
variety, which burns, giving a dense white fume of 
phosphorus pentoxide, which marks the position of the 
bursting shell by day, and has conferred upon this 
type of “shell the name of ““woolly bear,” and a flame 
which performs the same function of marking the 
position by night. When, however, a fragment of such 
a shell inflicts a wound the phosphorus poisons it, and 
very serious complications ensue. 
Probably the phase of “ frightfulness”’ that interests 
the British public as much as any is the bombs 
dropped by aeroplanes and Zeppelins, of which several 
distinct varieties are in use. 
Besides these, incendiary bombs are used, which 
differ somewhat from those used by the enemy, and 
which for manifest reasons cannot be discussed. The 
incendiary bombs used by the Germans consist of an 
outer skin wound round with tarred rope, and contain- 
ing a charge composed of a mixture of very finely 
divided aluminium and oxide of iron, which when 
ignited develops an enormous amount of heat owing 
to the combination of the oxygen of the oxide of iron 
with the aluminium. 
This mixture is known in trade as ‘“‘thermit,’? and 
was successfully introduced for practical use by Gold- 
schmidt in 1898; it is now largely used for welding 
rails and other iron and steel structures, and also for 
repairing castings, indeed, for any purpose for which 
intense local heating is desired. In many of these 
bombs there is a layer of amorphous phosphorus at 
the base, which converted into phosphorus vapour by 
the heat of the thermit reaction burns with a rush 
of poisonous flame, igniting everything around, giving 
burns which, if not fatal, are poisoned and most 
difficult to get to heal, and also producing a cloud of 
fumes of phosphorus pentoxide. 
UNIVERSITY AND EDUCATIONAL 
INTELLIGENCE. 
Liverpoo.t.—Prof. R. Robinson, of the University 
of Sydney, has been appointed to the newly constituted 
chair of organic chemistry. The University has re- 
cently received the sum of 10,0001. from Mr. Heath 
Harrison for the endowment of the chair. Prof. 
Robinson, who will fill the chair, was a student 
of the University of Manchester, where in 1909 
he was appointed assistant lecturer. He is well 
known for his investigations in conjunction with Prof. 
W. H. Perkin on the constitution of brazilin and 
hematoxylin, the synthesis of narcotine, and the con- 
stitution of strychnine, brucine, harmine, harmaline, 
etc. He was appointed to the chair of organic chem- 
istry at Sydney in 1912. 


Pror. J. Mascart, director of the Lyons Observa- 
tory, informs us that the city of Lyons has commenced 
the formation of a War Library, to contain a collec- 
tion of works and documents on the events of 1914-15. 
