_g. Examining fuel._ Lift the paddle quickly. If the mixture drops or runs from the paddle, additional stirring is necessary. When the paddle comes out clean, except for an adhering film, stirring should be stopped, provided there is no further visible settling of particles of thickener. _h. Loading shipping drums._ When stirring is completed, the mix is immediately bucketed (Fig 26) through a funnel into the shipping drum. The second bung hole should be open, if possible, to provide a vent to aid in pouring. Two men do the bucketing, each handling one pail so that the funnel may be kept loaded with mix and the shipping drum filled as rapidly as possible. Finally, the open-end drum should be picked up and its contents poured into the funnel. Not more than 50 gallons of thickened fuel should be loaded into a 55-gallon drum. The funnel should then be removed and replaced by a plug. The vent opening of the drum should also be closed. (See Paragraph 39 for pressure method of filling storage drums.) _i. Unused thickener._ Any thickener remaining in opened cans should be discarded. Since moisture in the air can quickly ruin its properties, no attempt should be made to save it. _j. Aging and storing._ Newly mixed fuel has the appearance of tapioca pudding. (Fig 27) It should preferably be stored overnight before use. It may, however, be fired within 1 hour after mixing. To keep fuel in good condition, drums for shipping and storing must be clean, moistureproof, dry, strong, and unrusted, but not galvanized. They must be kept tightly closed and should be laid on their sides so that rain water will not collect around the bungs. _k. Testing fuel._ Before use on missions, all fuels should be tested by being fired from a flame thrower. This is advisable because the characteristics of the fuel ingredients often vary. [Illustration: Fig 27. Contrasting newly mixed thickened fuel (right) with aged fuel (left).] 36. PREPARATION OF LIQUID FUELS. _a. Choice of ingredients._ Thin fuels are easy to ignite, but they lack range and are largely burned in flight before reaching the target. For this reason, liquid fuels should contain the lowest proportion of gasoline and the highest proportion of heavier oils that permits easy ignition. In hot climates, less gasoline is needed than in cold climates. Exactness of proportion, however, is not of great importance. Suitable blends are as follows: (1) Equal parts by weight or by volume of gasoline, light fuel oil, and heavy (bunker) fuel oil. The light fuel oil can be either No. 1 fuel oil, No. 2 fuel oil, automotive diesel oil, or kerosene. (2) One part gasoline to four parts of cleaned crankcase drainings. (Par 36_e_) Unused motor lubricating oil can be employed in place of crankcase drainings, but usually it will be unavailable for flame-thrower use. _b. Preparation of ingredients._ Before mixing blends, the following steps should be taken: