(1) Keep blast furnaces in a condition where they must be frequently shut down for repair. In making fire-proof bricks for the inner lining of blast furnaces, put in an extra proportion of tar so that they will wear out quickly and necessitate constant re-lining. (2) Make cores for casting so that they are filled with air bubbles and an imperfect cast results. (3) See that the core in a mold is not properly supported, so that the core gives way or the casting is spoiled because of the incorrect position of the core. (4) In tempering steel or iron, apply too much heat, so that the resulting bars and ingots are of poor quality. (b) Other Metals No suggestions available. (4) _Production: Mining and Mineral Extraction_ (a) Coal (1) A slight blow against your Davy oil lamp will extinguish it, and to light it again you will have to find a place where there is no fire damp. Take a long time looking for the place. (2) Blacksmiths who make pneumatic picks should not harden them properly, so that they will quickly grow dull. (3) You can easily put your pneumatic pick out of order. Pour a small amount of water through the oil lever and your pick will stop working. Coal dust and improper lubrication will also put it out of order. (4) Weaken the chain that pulls the bucket conveyers carrying coal. A deep dent in the chain made with blows of a pick or shovel will cause it to part under normal strain. Once a chain breaks, normally or otherwise take your time about reporting the damage; be slow about taking the chain up for repairs and bringing it back down after repairs. (5) Derail mine cars by putting obstructions on the rails and in switch points. If possible, pick a gallery where coal cars have to pass each other, so that traffic will be snarled up. (6) Send up quantities of rock and other useless material with the coal. (5) _Production: Agriculture_ (a) Machinery (1) See par. 5 b. (2) (c), (d), (e). (b) Crops and livestock probably will be destroyed only in areas where there are large food surpluses or where the enemy (regime) is known to be requisitioning food. (1.) Feed crops to livestock. Let crops harvest too early or too late. Spoil stores of grain, fruit and vegetables by soaking them in water so that they will rot. Spoil fruit and vegetables by leaving them in the sun. (6) _Transportation: Railways_ (a) Passengers (1.) Make train travel as inconvenient as possible for enemy personnel. Make mistakes in issuing train tickets, leaving portions of the journey uncovered by the ticket book; issue two tickets for the same seat in the train, so that an interesting argument will result; near train time, instead of issuing printed tickets write them out slowly by hand, prolonging the process until the train is nearly ready to leave or has left the station. On station bulletin boards announcing train arrivals and departures, see that false and misleading information is given about trains bound for enemy destinations.