Man has unquenchable thirst for knowledge. He is never asatisfy with what he already bknow and cwant to know and esee more and more. This curiosity for fknow more has ginspire him hundertake and icarry out difficult and dangerous tasks which eventually jresult in epoch making discoveries and inventions and k — lead him in his long and continuous journey from his helpless state of caveman to his present situations of power and progress. He l — be helpless still now, he would not have m — be able to control all powers and forces. n — invent so many technologies he now controls almost all destructive powers and forces.