Mine lllumination

CIM Bulletin1955
W HILE DIGGING caves and underground passages for li ving quarters, primitive man must have had some means of illumination. Most likely he used pieces of wood or slim 'bundles of r eeds or grasses as torches, perhaps steeped in animal fats to give more light. If this is so, we may accept these as the first means of underground illumination. Very little was clone to irmprove lighting deviees for many generations, but slowly there was developed a foun't holding fatty oils, with a spout in which was inserted a form of wick.
Accés complet à Document technique
Version PDF pour 20,00 $
Autres documents dans CIM Bulletin1955