Science for beginners . echanicalMotors: Water Motors; Available Water Power of theUnited States; The Steam Engine; The Gas Engine; Gas-oline Motors and Aeroplanes. SCIENCEFOR BEGINNERS CHAPTER I THE PRODUCTION AND USE OF LIGHT I. PRIMITIVE LIGHTING i. The Discovery of Fire.—There probably was a timewhen primitive man was without fire. In those days he hadno artificial heat or light, and heate his food uncooked. Perhapsman first obtained fire from deadtrees ignited by lightning, per-haps from oil wells which areknown to have been burning forcenturies. With fire camewarmth, light, and cooked fo
Science for beginners . echanicalMotors: Water Motors; Available Water Power of theUnited States; The Steam Engine; The Gas Engine; Gas-oline Motors and Aeroplanes. SCIENCEFOR BEGINNERS CHAPTER I THE PRODUCTION AND USE OF LIGHT I. PRIMITIVE LIGHTING i. The Discovery of Fire.—There probably was a timewhen primitive man was without fire. In those days he hadno artificial heat or light, and heate his food uncooked. Perhapsman first obtained fire from deadtrees ignited by lightning, per-haps from oil wells which areknown to have been burning forcenturies. With fire camewarmth, light, and cooked light from the camp fire alsofurnished protection from wildanimals. Gradually the fire cameto be the center of the home. Itis probable that we owe more thanwe realize to fire for what it hasdone toward building up andstrengthening home ties. 2. The Primitive Lamp.—Per-haps a pine knot snatched fromthe fire constituted the first portable light. How re-cently pine knots have been in common use is shown by the 1. Fig. 1.—A Roman Stories of Useful Inven-tions. (By courtesy of TheCentury Company.) 2 THE PRODUCTION AND USE OF LIGHT fact that Abraham Lincoln learned to read by the light ofthem. Perhaps by collecting the grease obtained from cook-ing and placing it in a rude vessel with a bit of bark or athread of twisted moss for a wick, man made the first would consider the light produced by such a lamp a poorone indeed, but the Eskimos still use such primitive bowl is hollowed out from soapstone; the fat comes fromthe animals they slay. The Eskimo lamp serves also as astove. By its heat all their cooking is done and their snowhuts are warmed. 3. Greek and Roman Lamps.—The lamps of Greece andRome were no better than the Eskimo lamps of today, butthe lamp bowls were often very costly and elaborately orna-mented (Fig. 1). The rich used lamps of bronze or silver;the middle classes, lamps made of terra-cotta; the poor, cheapiron lamps. 4. The Ea
Size: 1308px × 1911px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectscience, bookyear1921
