One of the first shocks you get when you start your visit through a cartridge factory is the matter-of-fact way in which the operatives, girls in many cases, handle the most terrible compounds. We stop, for example, where they are making primers to go in the head of your loaded shell, in order that it may not miss fire when the bunch of quail whirrs suddenly into the air from the sheltering grasses. That grayish pasty mass is wet fulminate of mercury. Suppose it should dry a trifle too rapidly. It would be the last thing you ever did suppose, for there is force enough in that double handful to blow its surroundings into fragments. You edge away a little, and no wonder, but the girl who handles it shows no fear as she deftly but carefully presses it into moulds which separate it into the proper sizes for primers. She knows that in its present moist condition it cannot explode. [Illustration: INSPECTING METALLIC SHELLS] [Illustration: EXAMINING PAPER SHELLS] [Illustration: WEIGHING BULLETS] Or, perhaps, we may be watching one of the many loading machines. There is a certain suggestiveness in the way the machines are separated by partitions. The man in charge takes a small carrier of powder from a case in the outside wall and shuts the door, then carefully empties it into the reservoir of his machine, and watches alertly while it packs the proper portions into the waiting shells. He looks like a careful man, and needs to be. You do not stand too close. [Illustration: SHOOTING ROOM OF BALLISTICS DEPARTMENT] [Illustration: CHRONOGRAPH FOR MEASURING] The empty carrier then passes through a little door at the side of the building, and drops into the yawning mouth of an automatic tube. In the twinkling of an eye it appears in front of the operator in one of the distributing stations, where it is refilled, and returned to its proper loading machine, in order to keep the machine going at a perfectly uniform rate; while at the same time it allows but a minimum amount of powder to remain in the building at any moment. Each machine has but just sufficient powder in its hopper to run until a new supply can reach it. Greater precaution than this cannot be imagined, illustrating as it does that no effort has been spared to protect the lives of the operators. [Illustration: PUTTING METAL HEADS ON PAPER SHOT SHELLS] It is remarkable that, in an output of something like four million per day, every cartridge is perfect. Such things are not accidental. The secret is, inspection. ~TESTING MATERIALS AND PRODUCTS~