The British Army used a variety of methods to control malaria, with anti-mosquito creams and mosquito netting being two of the best known. However it was far better to destroy the mosquitos before they even became airborne, so it was common to treat stagnant pools of water to kill the insects larvae. Oil was often used which clogged up the larvae’s breathing tubes, however other methods were also employed, as described by the 1934 Army Mannual of Hygiene and Sanitation:
Paris Green is a green powder containing arsenite of copper, is practically insoluble in water, and is a most effective larvicide. It is mixed with road dust, sawdust or some other similar material to keep it afloat and is then sprayed on the surface of the water. The particles are eaten by anopheline larvae, which are surface feeders, and the chemical acts as a poison. To be effective against culicine lavae, which feed below the surface, Paris Green must be mixed with wet sand or some other material which will carry it below the surface of the water.
Paris Green is most effective for large areas of water which cannot be controlled effectively by oiling. The quantity required is about one pound of Paris Green to the acre and the dilution with dust should be about 5 per cent. For large areas of water and about 1 per cent for small.
It has no effect on domestic animals, fish, or crops such as rice, and the water treated is not rendered unfit for domestic purposes; its disadvantages are that it does not kill pupae and, as it contains arsenic, care must be taken by persons handling it.
Tonight we are looking at a dust gun, used by the British military, to deliver this compound. My thanks go to Owen Thompson who kindly helped me add this one to the collection. The dust gun is a large tinplate pump, painted green, designed to spray out the dust and Paris Green mix:At the front is a large screw on lid that can be removed to refill the dust compartment:Onto the main dust container is riveted a small maker’s plate:The words ‘TOP’ are stencilled onto the dust gun canister to ensure it is used the right way round:At the end of the dust gun is a wooden handle:This is connected to a metal rod inside, with a rubber bung on the end:This creates a seal so that as the pump is moved back and forth the air pressure forces the dust mixture out of the nozzle at the opposite end:This nozzle has snapped off, a similar dust gun on the IWM website has a nozzle almost twice as long. The handle has stamped onto it the /|\ mark and a date of 1946:Although the 1934 hygiene manual described Paris Green as safe in the prescribed quantities, it is now known to be highly toxic if used in higher concentrations, as discovered by some users in North Africa during the war:
Mosquitoes and malaria were a big problem in that area, and so very strict measures were taken to control them. We had already lost one driver, Albert Fairclough, from Yorkshire. He was sent back to England as incurable, having had constant malaria over some nine months.
The main control was to mix up one shovel full of Paris Green arsenic with 50 shovels full of sand, mix well and spread over all the pools of water within half a mile of the camp. When the anopheles mosquito larvae finally came up for air, this poison was sucked in, and it was goodbye to yet another mosquito before it could take flight.
One poison party was supervised by a corporal, not the brightest star in the firmament, who confused the instructions. Thus, when the villagers’ cattle came to drink, they keeled over … dead! Naturally, the buzzards came to clean up the environment — they also keeled over … dead. Now the North African vulture is a gourmet meal for many villagers, and so we had a local hospital full of very sick villagers.
It was understood by many that a promissory note was handed over to the headman of the village. The note had been signed — on the spot — by one Winston S Churchill. It was just as well that we were on our way to the real war in Italy.