Smoke

[PhilB]

According to Wiki, the basic smoke formula is fairly simple:-

"A simple smoke powder can be made by gently mixing saltpeter (potassium nitrate, KNO3) and sugar in roughly a ratio of 60% saltpeter to 40% sugar; add more sugar for a slower burn and more KNO3 for a faster burn. The more finely ground the saltpeter and sucrose, the better the smoke bomb.

This formula has a variant in which the ingredients are left in powder form and the granulated sugar is replaced with powdered sugar.

More success could potentially be enjoyed when one adds another flammable substance to the mixture without "cooking" it. The best choice for this is melted paraffin."

I'd be surprised if WW1 smoke, at least in the early years, was much more sophisticated. Now, where are those artillery experts...

[johnreed]

Here is drawing of a 18 Pdr WP Smoke round. One of the problems using WP is that the smoke tends to pillar base ejection smoke is a better mode of producing smoke for blinding I am now going to find out whnen the first BE Smoke rounds were produced.

John

[johnreed]

The idea of a Base Ejection Smoke around the 1920's but was not developed until the 1930's due to cost, it was based on a shell containing two or more canisters containing a smoke mixture based on hexachlorethane and powdered zinc, was packed into the canisters each had perforated tube running through its centre. Two or more of these canisters could be packed into the shell body, topped with a pusher plate and an expelling charge. And the base of the shell was either screwed or pinned in place. A time fuze at the nose of shell ignited the expelling charge at the designated time, the expelling charge exploded, and the flash passed down the central tubes of the smoke pots and lgnites the smoke composition. The pressure due the explosion bursts open the base of the shell allowing the canisters to fall to the ground where they continued to produce smoke, because the smoke produced by the composition was cool it stuck close to the ground to make a continuous screen, the optium height of ejection was 100 feet or 30 m.

John

[Robert Dunlop]

Phosphorus smoke weapons are also very useful against personnel, as the splashing phosphorus goes into locations that shrapnel may not be able to access (eg: behind solid cover)...

Thermite was used in combination with air-burst WP shells for this reason. A very nasty combination!!

Robert

[johnreed]

In the 4.5 in Howitzer the Incendiary Shell used a T & P 80 or82 fuze hence airburst and the 4.5in W.P shell was fuzed with 106E D.A. ground burst only.

John

[PhilB]

Does that mean that one couldn't usually say whether a particular percussion nosecap was from a smoke or HE shell? Or, if timed, from a smoke or a shrapnel shell?

[centurion]

When in the 1930s the British Government belatedly realised that they might have to do the whole thing again a study was made of gas and smoke weapons as used in WW1. The following extracts may be relevant.

"Screening smokes. Various chemicals may be used to provide smoke screens for concealing important areas or buildings. Such substances as phosphorus, chlorosulphonic acid, titanium-tetrachloride, and a number of the chlorinatedhydrocarbon series are utilised for this object, while phosphorus may also be used in bombs for incendiary purposes. These smokes are non-toxic in the open, but serious effects may follow the bursting of the bombs at close quarters

Screening smokes.

Smoke may be used for screening important positions or the movements of troops; it may also be employed to mask a gas cloud, or to extend its flanks so as to conceal its actual frontage. Such screening smokes may be generated from solids dispersed from shell or bombs, or from liquids sprayed from aircraft or land vehicles.

Screening smokes are irritating when inhaled in close proximity to their source, but they are not toxic in the concentrations that render them effective as screens; under ordinary conditions troops can operate in them without wearing respirators, while in higher concentrations they may be irritant yet without producing toxic effects.

A dangerous and possibly asphyxiating concentration, however, may arise if a smoke shell burst at, or close to, the entrance of a dug-out, while proximity to a bursting phosphorus smoke shell may result in very severe burns from flying particles of burning phosphorus.

Apart from these possibilities, the chief danger associated with the use of screening smokes arises through accidental contact with the chemicals used in their production. These chemicals are all corrosive or dangerous to handle, and accidental contamination of the eye or splashes on the skin with the liquids will result in severe ulceration or burns. With a view to preventing such accidents, it is essential that operators should wear protective goggles or respirators, thick gloves and special clothing.

Should contamination with the liquid chemicals occur, first aid treatment must be undertaken immediately. If the eye be affected prompt and copious lavage with water, or with sodium bicarbonate solution in warm water, may mitigate the resulting effects. Splashes on the skin should be treated with excess of water in order to dilute rapidly and wash away the corrosive liquid, while any article of clothing contaminated by the chemical should be discarded at once.

The respirator gives efficient protection against all the screening smokes, and clothing is not affected by exposure to them in the concentration met with in the open.

Chlorosulphonic acid (C.S.A.).

This is a fuming, highly corrosive liquid which, on contact with quicklime, gives off a thick white cloud closely resembling a dense mist. At close quarters this is sufficiently irritating to eyes and throat to necessitate the wearing of a respirator, but at a distance of 200 yards or more from the source of emission this can easily be dispensed with.

Owing to its highly corrosive nature, C.S.A. requires great care in handling; moreover in contact with water C.S.A. generates intense heat and acid may be scattered in all directions. It is necessary, therefore, that goggles or respirators and suitable protective clothing (such as oilskin or rubber coats, gauntlets and rubber boots) be worn by personnel when filling generators or otherwise working with the liquid.

Contamination of the eye with the liquid should be treated immediately with large quantities of water, followed by lavage with a 3 per cent. sodium bicarbonate solution; a few drops of castor oil and a light pad over the eye will assist in allaying the irritation.

Splashes on the skin should be flooded with water to remove the contaminant, and sodium bicarbonate solution should be applied locally thereafter. Drying should be effected by mopping up excess moisture gently with swabs of absorbent wool, and not by rubbing"

I have seen other material that suggests that exposure to C.S.A as a smoke screen may not be as harmlees as suggested above. I suppose its a matter of risk anaysis.

"Private Atkins, you has a choice. You may proceed towards the enemy's trenches through a cloud of smoke which may have long term efects on your health or you can dispense with this and continue in full view of all them German gentlemen with the rifles and machine guns. - You choose". Not that in relity he was given any choice but you see the point (I hope).

[PhilB]

I get the impression that troops advancing through CSA smoke would need to wear respirators, which we have been told were not required? No use tricking the defenders into wearing masks if the attackers also have to!

[bob lembke]

Thermite was used in combination with air-burst WP shells for this reason. A very nasty combination!!

Robert

I have a vivid memory of a New York Times article of 1982 which made the danger of White Phosphorus very clear.

The Times reporter was visiting a Beruit hospital during the siege and shelling of Beruit in 1982, which lasted something like six weeks. The reporter's guide was a doctor trained at the John Hopkins med school at Baltimore, Maryland. (The attached hospital was just rated as the best hospital in the US). The doctor went to a big bucket of water in an alcove, and fished out a six week old baby with some implement, one of two twins in the bucket. The baby, who had been submerged for at least a day, immediately burst into flames, having been splashed with Israeli WP in the bombardment of the city. The doctor hurredly pushed the baby under water. The hospital did not know how to safely dispose of the babies, or safely return them to the parents or family.

I had not read this while I was on the receiving end of WP shells at Fort Devons, MA, at the hands of other officer cadets, but I knew enough to not be pleased at the error. I guess that the WP was used, as someone posted, so that the strike of the shells could be readily spotten, more so than HE, for training purposes. But not on a "friendly" rifle range. WP does not make a smoke screen that you want your troops to advance thru.

Bob Lembke

[Robert Dunlop]

I agree with your last comment, Bob. It is useful for screening off flanks and other areas that pose a threat to attacking troops.

Robert

[Robert Dunlop]

This German battlemap of the Cambrai battlefield illustrates the smoke barrages (thick white lines) used by the British on 20th November, 1917.

Robert

[PhilB]

Thanks, Robert. Never seen a smoke barrage marked on a battle map before!

[centurion]

QUOTE (Phil_B @ Jan 4 2008, 03:37 PM) <{POST_SNAPBACK}>

I get the impression that troops advancing through CSA smoke would need to wear respirators, which we have been told were not required? No use tricking the defenders into wearing masks if the attackers also have to!

In fact if you read that government paper I posted it specifically says that you don't need a mask unless you are within 200 yards of the point from where it is being generated

[johnreed]

I have ammunition books like Treatsie of Ammunition 1905,1915,Text Book on Ammunition 1926,1936 and User Handbook for Field Branch Artillery 1958 plus quite a few more. There is no mention of using CSA as a smoke producing agent even in the latest book. The smoke producing composition as I said previously was hexachlorethane and powdered zinc, one of the main factors in using a smoke composition was the storage and transport of the ammunition. CSA is very corrosive and if it comes into contact with water it explodes according to the hazaard sheets it may have been considered by a committee but not approved. With regards to post no 34 regarding WP when transporting WP ammunition we carried a Copper Solution Soap to cover any WP burns before it is treated in hospital. With regards to fuzes from exploded ammunition it would be very difficult to tell which calibre and type ammunition they came from.

John

[PhilB]

In fact if you read that government paper I posted it specifically says that you don't need a mask unless you are within 200 yards of the point from where it is being generated

I saw that. But if the smoke is to mask you from the enemy, then you have to pass through it to get to him. This may be difficult if you have to keep 200m clear of any smoke source!

[centurion]

SOP for smake screens produced from smoke generators is to let the smoke drift along the front between the force you wish to concleal and the enemy (not from the generator directly towards the enemy). In this case it covers a wide front and the troops passing through it would be some way from the source of generation.

[PhilB]

There's more to this smoke business than first appeared!

Do I take it that the smoke producing composition in 1914 was hexachlorethane and powdered zinc, then? In shells, mortars and grenades/rifle grenades?

Incidentally, I believe hexachloroethane is an insecticide, so at least the men get deloused as they pass through the smoke!

[shaymen]

Stumbled across this in the 11th Bn Sussex war diary.

Thought it might add to a very interesting thread.

Glyn

[Robert Dunlop]

It is. Thanks Glyn. What was the date?

Robert

[johnreed]

Smoke candles only last 4 minutes.

John

[centurion]

Glyn

Do you know if the 2nd Lt Blunden mentioned was the Poet and Author Edmund Blunden (Undertones of War)?

[jhill]

Another example of an operation order referring to smoke is this example from the Canadian Corps General staff in preparation for the Hill 70 show in August of 1917. In this case the Special Companies of the Royal Engineers were also to project drums of blazing oil onto the German positions.

Although the order gives the main purpose of the oil as to harass and demoralize the enemy, Nicholson mentions that it also added to the smokescreen, and, indeed, when the oil burned out the advance was held up.

[Robert Dunlop]

Thanks very much for posting the details. It would also have been one or more of the Special Companies that operated the 4" Stokes mortars providing the smoke screen. The right flank represented a major threat to the advance onto Hill 70, as proved in the abortive attempts to recapture the hill and advance beyond it during the Battle of Loos.

Robert

[bob lembke]

QUOTE (Phil_B @ Jan 4 2008, 04:55 PM) <{POST_SNAPBACK}>

There's more to this smoke business than first appeared!

Do I take it that the smoke producing composition in 1914 was hexachlorethane and powdered zinc, then? In shells, mortars and grenades/rifle grenades?

Incidentally, I believe hexachloroethane is an insecticide, so at least the men get deloused as they pass through the smoke!

Phil;

This raises another question. Many or all nerve gasses are insecticides. This is a bit of a problem, due to the ease of dual use; i.e., when the civilized powers feel that developing countries should not have military nerve agents, does this mean that they should not be allowed to produce insecticides? (An interesting but OT aside: The Guardian reported, about three years ago, that the nerve gasses that Saadam H. used to spray the Kurds were produced in an "insecticide" plant supplied to Saadam during the 1980's under UK government commercial guarantees, during Saadam's war of aggression against Iran, which we supported. When Saadam unaccountably did not forward the final payment for the dual purpose plant when the First Gulf War broke out, the guarrantees were so strong that the UK government cut a 25 pound check to the commercial firm to provide the final payment.)

So how benign was this hexachloroethane?

In the same vein, the notorious Zyklon B was a commercially produced de-lousing insecticide, used after the war in Europe to perform humanitarian de-lousing. More evidence that insecticide is not benign stuff.

Sounds like the hexachloroethane/zinc smoke process was not as harmless as we may be imagining, perhaps in the long run. Is this true?

Bob Lembke

[shaymen]

It is. Thanks Glyn. What was the date?

Robert

Robert 26th Setember 1916.