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Show Nothina WHAT would bo your definition of "nothing"? Perhaps you would 6ay 'fin absence ab-sence of anything." You take the ltd off an empty box and say, 'There Is nothing in it." But there fs something in the box It is full of air. Take, however, a common electric incandescent lamp, and (barring the glass rod and the delicate filaments supported by tho rod) it contains literally lit-erally nothing. There Is a vacuum inside. in-side. If tho bulb contained air, the oxygen would soon burn up tho filaments which Is why a vacuum Is necessary. Tt will be noticed that the bulb terminates ter-minates In a little tip. When the bulb was made at the factory it had a glass tube extending from the point where you see the tip Through this tube the air was pumped out of tho bulb, SUnl then the tube was bitten off, so to speak, close to the bulb with a khj. blower's flame, which incidentally sealed the lamp, rendering It alrproof. In other words, the vacuum was sealed up inside, and it represents an almost absolute emptiness. Inasmuch as there Is only about one-ten thousandth thou-sandth as much air In the bulb as it would contain If there were a small hole in It. By the uso of an ingenious contrivance, con-trivance, to which a dozen bulbs in process of manufacture can be attached, at-tached, the air is exhausted from all of them simultaneously by one pump Largo incandescent lamps are sometimes some-times filled with pure nitrogen, instead in-stead of exhausting the air from them. It is cheaper, and that -. being Inert, does not affect tho filament. Tho vacuum bulb represents In effect a hole in the air. If It be broken there is a loud "implosion" a bursting Inward, In-ward, caused by the rush of air |