Smoke

[shaymen]

Glyn

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

Sorry, no idea.

[shaymen]

Had to smile at the code word used

'Gaspers' - very apt

Glyn

[johnreed]

Further to my posts #28 and #39 I quote from Text Book on Ammunition 1936 on page 44 "Hexachlorethane mixtures in solid for are gradually assuming more importance as fillings for smoke shell and grenades. Their dry compositions eliminates the possibilty of leakage, making them quite safe in storage and transport. Their superiority over white phosphorous in smoke production is also marked both in density of the cloud and period of emission.

The basic principle of these compositions is that of associating a highly chlorinated substance with zinc oxide to produce zinc chloride. The latter is volatile and very hydroscopic, picking up moisture from the air to form a dense cloud. There is little heat in the re-action and for this reason "pillaring" which was an objectional feature of the white phorphorus types, Does not occur.

From Text Book on Ammunition 1926 page 40 "Chlorsulphonic Acid and mixtures of chlorsulphic acid with sulphur trioxide, when vapourised, produce an efficient screening smoke composted of minute drops of sulphuric and hydrochloric acids in aqueous solution. A smoke screen can be readily formed by tanks, the chlorsulphonic acid being vaporised in the heated exhaust pipe".

I think I can see now why the the safer option of Artilley ammunition being adopted.

John

[bmac]

Smoke was extensively used at Gommecourt on 1st July 1916 (yes, I am a broken record!). It was provided by Stokes mortars (laid close to the German lines), P Grenades thrown into No Man's Land and smoke candles (made by famous names in the British firework business) located just in front of the British lines. The allocation of these latter two items was: 56th Division – 10,900 ‘P’ grenades, 21,600 Brock candles and 3,000 Pain’s candles; 46th Division – 13,600 ‘P’ grenades, 27,200 Brock candles and 3,200 Pain’s candles; and 37th Division – 8,000 ‘P’ grenades and 8,000 S.F. Co. and Brock candles. The candles apparently produced some pretty foul green, brown and yellow smoke.

There were various problems:

1. Neither Division rehearsed with the volume of smoke generated on the day. It was much thicker than anticipated and men lost their way and contact with colleagues within a few yards. There was particular confusion on the 46th Div front as some men advanced from the old front line and not from the newly dug advanced line and, in the chaos and being unable to see more than a few feet, decided the advanced trench was the German front line and decided to occupy it and could not be persuaded to move on. This could not be seen from the British lines and so no orders were sent out to get them moving until it was too late.

2. The trench mortar smoke was less thick than the hand and candle smoke meaning men tended to appear in the open as they passed through the thick smoke screen near to the British lines and in NML, their progress having been slowed by the confusion in the smoke. This badly affected the 46th Division.

3. Gommecourt was a salient with a southerly flank and a westerly flank. On the day the wind blew SW to NE. i.e. it blew across NML and over the German lines on the southerly front enabling the 56th Division to move into and over the German first three trenches in many places. It lingered on this front for nearly an hour in the hollow between the lines. On the 46th Div front the smoke blew parallel to the front lines slowly revealing the right wing of the Division's attack and, with the trench smoke drifting away rather quickly to the N,E giving German MGs a clear view of the troops advancing over the last few yards.

4. The smoke did not disperse but carried on moving NE and into the woods and hollows behind the German lines in which were located the German artillery. The reduced observation of the RFC meant the counter-battery work of the British guns was extremely ineffective on a front with the highest concentration of German artillery anywhere on the Somme on 1st July.

In addition, on the 46th Div front there are various accounts of wounded men dropping smoke bombs in their own lines slowing the already exit of the men into NML.

Generally, therefore, a real mixed blessing compounded by some poor staff work in the rehearsals, bad luck and the weather.

Fog, however, the 46th Division might have had a higher regard for as it helped them considerably in their taking of the St Quentin Canal in autumn 1918!

[PhilB]

Would mortar shells, ‘P’ grenades, Brock candles and Pain’s candles all have similar chemical make up? Or are P grenades the odd ones out, being phosphorus?

[Robert Dunlop]

Thanks for the details, Bill. Your information points to the fact that generating smoke from the front lines caused more problems than cures. While the smoke may screen the troops going over the top, it makes things worse once troops navigate their way out of it into the clear. It is very helpful to see the critique of the Stokes-generated screen.

Robert

[centurion]

Looking at the use of smoke in conjuction with tanks it appears to have been useful when used to conceal the initial tank assault on specific objectives (as at the second attack at Langemark - St Julien) or to provide cover from German anti tank guns ( as happened at Moreuil, Harpon Wood when the commander of a lead tank which was knocked out succesfully laid a smoke screen to protect the tanks following him. However when, as at Catelet- Boney, the wnd changed and the whole battle field was covered in smoke it could severely hamper tank/infantry cooperation.

Smoke seems to have been useful when used in controled and specific tactical circumstances