in the early 1800´s the firs
time lectricity was available
for cities lke new york
Even thongh ligth bulos were
produced the network was not
ready yet for mass distriburion
electricity presented some danger because
it could nor be seeen as is travelled through
the wires so it was important to wam
people about the hazards of this amazing
new invention
To avoid oxygen from burhing the
filamen it wasextracced from the bulb
creating a vacuum
today´s light bulbs are
basically the same but the
marerials have changt