Allen, Charles Ricketson, 1862- [from old catalog] · New York, H. Holt and company · leaf 125
wnlow, the flame sometimes runs down to the bottom of thetube, and burns at the point where the gas enters.* Thisis called backing-down, and is often indicated by theflame taking a green color. Backing-down should bestopped at once, as it will make the lamp very hot, some-times even hot enough to… … * Partially closing the sleeve when tbe gas is turned low tends toprevent this. 112 BOW BEAT TRAVELS. 113 Precautions in Heating.—If a flask is nearly full ofwater, it is fairly safe to heat it directly, but care must beused that the flame strikes the glass nowhere above thelevel of the water. Test…
Physics
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