with its effectiveness, by removing stop-plugs from lubricating systems or by puncturing the drums and cans in which it is stored.
(c) Cooling Systems
(1) A water cooling system can be put out of commission in a fairly short time, with considerable damage to an engine or motor, if you put into it several pinches of hard grain, such as rice or wheat. They will swell up and choke the circulation of water, and the cooling system will have to be torn down to remove the obstruction. Sawdust or hair may also be used to clog a water cooling system.
(2) If very cold water is quickly introduced into the cooling system of an overheated motor, contraction and considerable strain on the engine housing will result. If you can repeat the treatment a few times, cracking and serious damage will result.
(3) You can ruin the effectiveness of an air cooling system by plugging dirt and waste into intake or exhaust valves. If a belt-run fan is used in the system, make a jagged cut at least half way through the belt; it will slip and finally part under strain and the motor will overheat.
(d) Gasoline and Oil Fuel
Tanks and fueling engines usually are accessible and easy to open. They afford a very vulnerable target for simple sabotage activities.
(1) Put several pinches of sawdust or hard grain, such as rice or wheat, into the fuel tank of a gasoline engine. The particles will choke a feed line so that the engine will stop. Some time will be required to discover the source of the trouble. Although they will be hard to get, crumbs of natural rubber, such as you might find in old rubber bands and pencil erasers, are also effective.
(2) If you can accumulate sugar, put it in
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