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Proposals from individuals and themselves to initiate Proposals.
All possible means will be used to enlist the interest and secure the co-operation of persons directly engaged in trade and industry.
(8) It is contemplated that the Advisory Council will work largely through Sub-Committees reinforced by suitable experts in the particular branch of science or industry concerned. On these Sub-Committees it would be desirable as far as possible to enlist the services of persons actually engaged in scientific trades and manufactures dependent on science.
(9) As regards the use or profits of discoveries, the general principle on which grants will be made by the Committee of Council is that discoveries made by institutions, associations, bodies, or indviduals in the course of researches aided by public money shall be made available under proper conditions for the public advantage.
(10) It is important in order to secure effective working that the Advisory Council should be a small body, but it is recognised that even if full use is made by the Council of its power to work through reinforced Sub-Committees, its membership may be found inadequate to do justice to all the branches of industry in which proposals for research may be made or to the requests of other Government Departments for assistance. It is therefore probable that it will be found necessary to strengthen the Council by appointing additional members.
The first members of the Council will be:-The Right Hon. Lord Rayleigh, O.M., F.R.S., Mr. G. T. Beilby, F.R.S., Mr. W. Duddell, F.R.S., Prof. B. Hopkinson, F.R.S., Prof. J. A. M'Clelland, F.R.S., Prof. R. Meldola, F.R.S., Mr. R. Threlfall, F.R.S., with Sir William S. M'Cormick as administrative chairman.
(11) The Advisory Council will proceed to frame a scheme or programme for their own guidance in recommending proposals for research and for the guidance of the Committee of Council in allocating such State funds as may be available. This scheme will naturally be designed to operate over some years in advance, and in framing it the Council must necessarily have due regard to the relative urgency of the problems requiring solution, the supply of trained. researchers available for particular pieces of research,
and the material facilities in the form of laboratories
and equipment which are available or can be provided for specific researches. Such a scheme will naturally be elastic and will require modification from year to year; but it is obviously undesirable that the Council should live "from hand to mouth" or work on the principle of "first come first served," and the recommendations (which for the purpose of estimating they will have to make annually to the Committee of Council) should represent progressive instalments of a considered programme and policy. A large part of their work will be that of examining, selecting, combining, and co-ordinating rather than that of originating. One of their chief functions will be the prevention of overlapping between institutions or individuals engaged in research. They will, on the other hand, be at liberty to initiate proposals and to institute inquiries preliminary to preparing or eliciting proposals for useful research, and in this way they may help to concentrate on problems requiring solution the interest of all persons concerned in the development of all branches of scientific industry.
(12) An Annual Report, embodying the Report of the Advisory Council, will be made to his Majesty by the Committee of Council and laid before Parliament. (13) Office accommodation and staff will be provided for the Committee and Council by the Board of Education.
MODERN MUNITIONS OF WAR.1
I. GUNS AND PROPELLANTS.
LEVEN months of war have now passed, and certain lessons have made themselves perfectly clear. The teaching of the first six months of the war was tersely summed up by General French when he said last February, "The problem set is a comparatively simple one-munitions, more munitions, always more munitions," the special munitions meant in this case being the high explosive shells that from the time the war assumed the conditions of a field siege after the battle of the Aisne became a necessity for any advance.
By "munitions" are meant practically everything required by the Army, and it will be well first to consider the wonderful changes which have taken place in guns and propellants, and which in this war have made artillery probably the most important feature.
Napoleon, himself an artillery officer, was fond of using massed batteries in much the same way as artillery is being used in the present war, but what artillery meant in those days and in these can perhaps be best grasped by remembering that the old Victory, which was our most heavily armed ship in the Napoleonic days, had a broadside of 52 guns, which, when fired simultaneously, would have thrown about 60 per cent. of the weight of the metal contained in one shot from the 15-in. guns of the modern super-Dreadnoughts. We must also remember that in the Crimean War the old smooth-bore 68-pounders, using a charge of 16 lb. of black powder, were the largest guns ashore or afloat at the time, whereas now we have the 15-in. guns of our super-Dreadnoughts, weighing close on 100 tons, from which a charge of 400 lb. of MD cordite hurls a projectile weighing 1925 lb. with accuracy to a distance of fifteen miles, or with high angle firing to double that distance.
The changes commenced in the 'fifties of the last century, when we adopted the idea of rifling ordnance so as on firing the gun to give the projectile a spin as well as forward velocity, this being found to add to the range and accuracy of fire, and in order to do this satisfactorily the guns had to be increased in length.
The rate at which the size of the big naval guns grew may be gathered from the fact that at the Siege of Alexandria in 1882 we had the So-ton guns of 16-in. calibre, whilst by 1886 we had afloat the 110-ton guns with a bore of 16.25 in., using a charge of 960 lb. of powder. It was soon found, however, that the lengthening of the gun when using the form of gunpowder then employed caused a strain on the breech and gave but a low muzzle velocity, this being due to the rapid burning of the powder. Attempts were then made to slow the combustion of the powder by increasing the size of the grain, and with the increase in the size of the guns the powder gradually grew to the large pebble powder, consisting of 12-in. cubes. Unfortunately the desired effect could not possibly be obtained by alterations of this character, as it is required of a perfect powder that when the charge is fired in the breech of the gun, the combustion shall commence comparatively slowly, so as to overcome the vis inertiae of the projectile without throwing too great a strain on the gun, and the combustion of the powder should then increase in rapidity so as to supply gas more and more rapidly to increase the pressure and momentum of the shot, which should leave the muzzle of the gun with the maximum velocity.
With such forms of powder as cubes or other large
1 Abstracts of three lectures delivered at the Royal Society of Arts on July 7, 14, and 21, by Prof. Vivian B. Lewes.
grain, however, maximum rapidity of burning and evolution of gas takes place at first, owing to the ignition spreading over the whole surface of the cubes, and instead of the gas coming off with more and more rapidity as the space in the gun became larger, the evolution rapidly diminished with the decrease of surface caused by the burning away of the powder.
In order, so far as possible,. to avoid this defect, built-up charges were resorted to, and it was General Rodman, of the American Service, who first tried to overcome the difficulty by building up the charge of solid slabs perforated with holes, from the interior of which the combustion was started, so as to expose the minimum surface of powder at first, whilst the enlarging holes produced a greater and greater surface of powder as the space behind the projectile increased.
Large perforated cakes, however, are always liable to break, and cannot be made of uniform density, so that it was found far better to mould the powder into hexagonal prisms with a central core through them, which could be built up into a charge, the prisms being made with such exactitude that when the charge was fired by a layer of fine grain powder at the base of the cartridge the combustion started from the central cores, and as the powder burnt away a greater and greater surface for combustion was continually formed until the whole of the charge was spent.
With the continued growth, however, in the size of the guns employed other changes became necessary, as even when using the black prism powder for builtup charges the pressure given began to throw too severe a strain upon the breech of the gun, even when the cartridges were made up in such a way as to leave air spaces at the seat of the charge. In order to relieve the initial pressure so far as possible, and to secure further modifications, alterations in the composition of the powder became necessary, so that by the time the 80- and 110-ton guns were introduced into the Naval Service prism powder containing an increased percentage of potassium nitrate and charcoal with a smaller proportion of sulphur were in use. This fitting of the powders to the guns enabled perfect ballistics to be obtained, and really converted the explosive into what Sir Frederick Nathan was fond of calling these powders-"propellants." These powders had one characteristic, however, in common with the old grain powder, and that was that they gave volumes of smoke, and when rapid-firing guns were introduced so dense was the cloud produced that after the first few rounds nothing could be seen, and the guns became useless until the smoke had cleared. This rendered a smokeless powder a necessity, and the history of the inception of the smokeless powders of to-day is full of interest.
In any successful explosive certain conditions have to be fulfilled; one must be able to concentrate in a small space bodies which will act upon each other independent of the air with enormous rapidity, forming the largest possible volumes of gas, which, expanded by the heat of the action and having to find a way for itself, gives the explosive effect. If this change takes an appreciable time, the body can be used as a "propellant" in a gun, and gunpowder is of this character. When, however, the change takes place practically instantaneously, it cannot be used in a gun, and is used in high-explosive shells, bombs, torpedoes, and mines; and such bodies we call "high explosives," nitroglycerin being an example of this class.
When during the formation of the gas from the solid in explosion other solid compounds are formed as well, these solids are blown out in a fused form as fine particles and form a cloud-smoke, but, if only gases are produced, the explosion is smokeless. Gun
down sufficiently to make an excellent propellant by destroying the original cotton structure that still existed in the nitro-cotton by gelatinising it with alcohol and ether, so forming a grain that can only burn from the exterior. If cotton fibre is examined under the microscope it is found to consist of very minute tubes, and in the process of converting the cotton into guncotton," by soaking it in a mixture of the strongest nitric and sulphuric acids, washing out all acid and drying, this structure remains. If the guncotton were used as a charge in a big gun, no matter how much it was compressed, the flame of the combustion would be driven back into these tubes and so accelerate the burning as to give almost instantaneous explosion, straining the gun and giving very low velocity to the projectile.
Nitroglycerin is an even more rapid explosive than guncotton, and if used in a gun would burst it, probably without driving out the projectile at all. Nobel, however, in 1875 discovered that if a low form of guncotton was macerated in nitroglycerin the guncotton was gelatinised, all structure disappeared, and both explosives became so tamed in their action that they were converted into a perfect blasting explosive; and in 1888 the mixture was made the basis of a smokeless propellant far superior to gunpowder. This idea was improved upon by Sir Frederick Abel and Sir James Dewar, who found that the highest form of guncotton, which is unacted upon by nitroglycerin, could be got into a gelatinised mass with nitroglycerin if a common solvent, such as acetone, was used to blend them, and afterwards evaporated out, and this blend with 5 per cent. of vaseline to increase the stability and lubricate the gun forms our modern "propellant" cordite, so named from the fact that it is cast into sticks, rods, or cords, according to the size of the gun in which it is to be used.
The "Mark I" cordite first made contained 68 per cent. of nitroglycerin, and the heat of its combustion in the guns gave rise to a troublesome form of erosion, which in the South African war shortened the lives of the field guns, which had to be re-lined after a certain number of rounds had been fired, and this led to an alteration in the proportion of the ingredients in the MD cordite now used in all arms, from the 15-in. guns of our super-Dreadnoughts to the Service rifles.
Our Allies and enemies alike use smokeless powders of a somewhat different type, made by gelatinising nitro-cotton without any nitroglycerin for their field artillery and rifles, but in the German and Austrian naval guns nitroglycerin powders of much the same kind as our "cordite" are used, as a larger charge of nitro-cotton powder has to be employed than of a nitroglycerin powder, and this means larger chambers in the guns and larger magazines to carry the necessary amount of explosive.
As may be imagined, the introduction of smokeless powder made an immediate change in gun construction, as much smaller chambers were needed, and the possibility of throwing the pressures further forward in the gun enabled them to be made lighter, and as a result our biggest naval guns are only 15 in. as against the 16-25-in. 110-ton guns in use in 1886, and the charge of MD cordite only 400 lb. as against the 960 lb. of prism powder, but the muzzle velocity has
increased by nearly 50 per cent., whilst the projectile is far heavier.
Our enemies in the field are using guns, howitzers and mortars, the two latter classes being used for indirect fire from behind shelter, for which their high trajectory specially fits them, whilst the field artillery used by them are chiefly quick-firing 77-millimetre guns (3.03 in.). One of the new features they have introduced into the present warfare is the use of siege guns of much larger size, transported by motors, and so made available for field work, whilst amongst the other artillery in use are the celebrated Krupp siege howitzers of 16-8 in. calibre, but probably the most deadly innovation has been the almost unlimited use of machine guns, to the perfecting of which the Germans have devoted many years, and of which they have an enormous supply.
II.-SHELLS AND HIGH EXPLOSIVES.
The shells used in big guns and field artillery may be divided into two main classes: shrapnel, which is utilised against troops in the field, and is of but little use against fortifications or trenches, and high explosive shells, which may be either armour-piercing or ordinary.
The shrapnel shell is a hollow cylindrical steel projectile packed with bullets, at the base of which is a bursting charge that may be gunpowder or high explosive, whilst in the nose of the shell is arranged the time fuse connected by a tube to the bursting charge, and so regulated that the shell can be exploded in the air at any desired point, the bullets and fragments of the shell being driven forward and spreading over a considerable area. The shrapnel used in the ordinary field gun is an 18-lb. projectile, containing 375 bullets, and when burst at the right altitude is a most deadly weapon against troops, especially when in massed formation. Since its invention by the officer whose name it bears, shrapnel has been looked upon in the Service as the form of shell most necessary in field operations, and during the present war our supplies have been ample for all requirements.
For fortified trench warfare, such as has been the characteristic feature of the fighting on the western front since September, shrapnel is not effective, as it does but little damage to earthworks, wire entanglements, and other defences, and this practically new phase of field warfare has to be met by the use of high-explosive shells, capable of detonating with such enormous concussive power as to destroy physical obstructions, crumble earthworks, clear wire entanglements, and reduce the defenders in the trenches to a dazed and stunned condition by the action of concussion on the heart and nerves.
Under the conditions created in the present war both classes of shells are needed in the field-the shrapnel to resist infantry attack, the high-explosive shells to clear the ground and prepare the way for attack on the enemy, and it has been an insufficiency in the supply of the latter which has given rise to so much criticism, mostly undeserved and wholly unwise. At the present time obstacles to supply in all directions have been surmounted, and a steady and ever-increasing stream of shell is flowing to the front.
The high-explosive shell is made of forged steel with comparatively thin walls and a heavy bursting charge, but the large naval shells and those for the siege guns, which have to penetrate heavy armour, are made from ingots of chrome or chrome-nickel steel, forged, hardened, and the nose capped with soft steel, which prevents the shell from shattering on impact with the hardened steel armour. These shells
also contain a heavy charge of high explosive, generally cast into the shell in a fused condition.
All these forms of shell are fitted with the usual. soft copper driving bands near the base of the shells; these bands take the place of the projections used in. the early forms of shell to fit the rifling of the gun. The copper band, under the pressure existing during the firing of the charge, is pressed into the grooves of the rifling in the gun, not only imparting rotation to the projectile, but also acting as a gas check to prevent the rush of the gas past the projectile, an action which had accentuated the serious erosion with Mark I cordite.
For trench fighting the grenade has now again come into use, and the most modern forms are in reality miniature shrapnel shells, which are fitted on to a rod that can be fired from a rifle, or, where the trenches are close together, can be thrown or slung by hand. The body of the grenade is made of steel or malleable iron so serrated as to break up on explosion into many pieces; it contains a charge of T.N.T., and a tetryl detonator fired on impact by a needle liberated only after the grenade has travelled a certain distance, so as to render premature explosion impossible. weight of such a grenade is about 23 oz., and when fired its range would be about 300 yards, but when hand-thrown not more than 40 or 50, and its flight through the air is steadied when fired by a rod, which for hand use is replaced by a rope tail.
One of the things that strikes the ordinary observer most when considering the composition of the explosives of to-day is that they are all derived from substances of the most commonplace and harmless description, and probably the greatest mistake the Government has made in this war was in not making cotton contraband from the commencement, and it is inexcusable that the mistake should not be rectified.
There is not the least doubt that Germany had enormous supplies of cotton at the commencement of the war, as well as huge quantities of manufactured explosive, but the factor which she had omitted to reckon on was the duration of the war, which was expected to be over last November. It has been calculated that Germany and Austria need 1000 tons of cotton a day, and it has been proved that the neutral European countries-Holland, Denmark, Sweden, and Norway-imported during the first three months of this year six times the amount they did in the corresponding period of last year, and there can be but little doubt as to where this enormous surplus went.
Directly there is any talk of making cotton contraband German articles appear in the Press of the neutral countries pointing out that it is not aimed at German explosives, but is England's attempt to corner the trade in textile fabrics, but for some inscrutable reason the Government has so far declined to do the one thing that more than any other would shorten the
We have seen that cotton and glycerin when nitrated and blended with vaseline yield cordite, which serves as a propellant in all our guns, whilst the high explosives used in shells, torpedo heads, mines, and aviators' bombs are almost entirely derived from coaltar derivatives by nitration. When coal tar is subjected to fractional distillation the portion which comes over up to a temperature of 170° C. is called "light oil," and contains all the compounds of low boiling point found in the tar, and, as we shall see, from this several of our most valuable explosives can be obtained. When these light oils have distilled over the next fraction or "middle oil" yields phenol or carbolic acid, a body which when nitrated gives picric acid, the basis of the French high-explosive melinite, the Japanese shimose powder, and the English lyddite.
Picric acid is a nitro-substitution product, three atoms of the hydrogen of the original phenol being
replaced by the radical nitryl, NO,, and it forms with metals a class of salts called "picrates." The potassium salt was suggested as a bursting charge for shells nearly fifty years ago, whilst Sprengel showed that picric acid itself could be detonated, and later Turpin employed the acid as an explosive. It was found possible to get a great weight of explosive into a small space, as the acid could be melted and poured into the shell in a molten condition. Picric acid per se is a very safe explosive, but has the drawback of acting on metals to form picrates, some of which are far more sensitive to disturbing influences than the acid itself.
Experiences with lyddite shells in the South African war showed their behaviour to be very erratic, some exploding with great effect, whilst others gave disappointing results, this being due to the fact that picric acid requires a powerful detonator for obtaining the highest explosive effect, and the use of such a detonator was dangerous, and might cause a premature explosion of the shell within the gun.
The disadvantages inherent in the use of picric acid led to attempts being made to replace it by some other material of the same character, which could be used as a high explosive in a bursting charge and yet be free from these drawbacks. Such a body was found in trinitrotoluol, and although its explosive force is slightly less than that of picric acid, the pressure of the latter being 135,820 lb. on the square inch, as against 119,000 for trinitrotoluol, yet its advantages more than compensate for this difference. Not being of an acid nature, trinitrotoluol, or T.N.T., as it is termed, cannot accidentally form more sensitive salts; it is without action on metals, and is perfectly stable. The formation of volumes of black smoke on detonation of the T.N.T. has given rise to the names given to shells containing this explosive of " Black Marias," coal-boxes," and "Jack Johnsons," and the fact that this cloud of carbonaceous matter is produced shows conclusively that the oxygen contained in the nitryl radical present in the explosive is insufficient for its complete combustion. An excellent explosive used during the Balkan war, and now largely employed by the Austrians, is known as ammonal, in which 12 to 15 per cent. of T.N.T. is mixed with an oxidising compound, ammonium nitrate, a little aluminium powder, and a trace of charcoal. This mixture gives even better results than the T.N.T. alone, and its only drawback is the hygroscopic character of the ammonium nitrate, which necessitates the material being made up in air-tight cartridges. It forms, however, a most effective bursting charge, and although the rate of detonation of the trinitrotoluol is reduced by the admixture of the oxidising compounds, the shattering effect is even more destructive than when the explosive is used alone, as the pieces of shell scattered are larger in size. An improved form of this explosive is being made on a large scale in England for use by the Allies, and renders the supply of high explosives for shells perfectly adequate.
Toluene is obtained from the crude benzol in coal tar and by scrubbing coal gas, by fractional distillation, and is also being produced synthetically from other hydrocarbons by the action of heat and pressure, so it is safe to say that any requirements for toluene to nitrate can be amply met.
Under the influence of nitration other constituents of tar are converted into effective explosives, dinitrobenzol being the basis of such mining explosives as "Roburite" and "Bellite," whilst trinitrocresol has been used largely in place of picric acid, under the name of “Ecrasite," but it shares with picric acid the drawbacks of forming more sensitive compounds with bases and of having an acid reaction.
Expert opinion has by no means settled which is really the best of the high explosives, and although it was the Germans who were chiefly responsible for bringing T.N.T. into such prominence, there are not wanting signs that they are largely reverting to picric acid.
Probably the most powerful explosive known is made from benzene by converting it into anilin, and by nitration making this into tetranitro-anilin, an explosive of which a great deal more will be heard, whilst another derivative tetranitromethylanilin, known as "tetryl," is being used largely for primers and detonators.
III. POISON GAS AND INCENDIARY BOMBS.
Some, like carbon dioxide, nitrogen, and hydrogen, act There are many gases known which are irrespirable. merely in the same way as water would do by cutting off the oxygen supply, which is a necessity to life, from the lungs, but have no toxic action on the system. Other gases, like carbon monoxide and cyanogen, are powerful poisons, less than 1 per cent. of which in the air will cause death by purely toxic action. Others again, like sulphur dioxide, chlorine, and bromine, may act by producing spasms of the glottis, and subsequent asphyxiation.
The use of asphyxiating gas is by no means the simple problem that one might imagine. In the first place, gases differ from other forms of matter in that the molecules of which they consist being free from cohesion, are able to intermingle, no matter how different may be their weights, a process which is known as diffusion," so that unless the gas is very considerably heavier than air it intermingles with the atmosphere so quickly as to prevent its spreading in a poisonous quantity over any considerable area. No gas which is not more than double the weight of air could be used effectively in sufficient quantity to be poisonous at the distances likely to exist between the trenches. It is this that accounts for the fact that although I per cent. of carbon monoxide is instantly fatal, no deaths can be traced to its effects during the war, although all our propellants and high explosives give on explosion large volumes.
The weight of a gas is represented by its density, that is, how many times it is heavier than hydrogen, the lightest gas known, and in the following table are shown the densities of the various gases suspected of having been used or possible to use, and the relation of their weight to an equal volume of air :
By the laws of diffusion gases intermingle at a rate which is inversely proportional to the square roots of their densities, but air currents or wind enormously increase the rate of admixture, so that with anything like a breeze blowing it would be impossible to use them successfully, whilst the opportunity for "frightfulness is, of course, limited by the direction of the wind, so that in Flanders it is only with the wind in the north or a point or two on either side that effective use could be made of them.
During the past few months the prevailing winds have been in the enemy's favour for considerably more than the normal period, and it is to be hoped that during the next few months with the prevalent wind from the south or south-west the opportunity of using these gases will be reduced to a minimum.
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 reasonable 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 volatilise, 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 yellowishgreen 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 compressed 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 temperatures 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 processes 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. Germany 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
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. Amorphous 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 nonpoisonous, 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 containing 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 Goldschmidt 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
LIVERPOOL.-Prof. R. Robinson, of the University of Sydney, has been appointed to the newly constituted chair of organic chemistry. The University has recently received the sum of 10,000l. 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 hæmatoxylin, the synthesis of narcotine, and the constitution of strychnine, brucine, harmine, harmaline, etc. He was appointed to the chair of organic chemistry at Sydney in 1912.
PROF. J. MASCART, director of the Lyons Observatory, 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.