Edison's incandescent light bulb, patented in 1880, was only one of several

revolutionary developements.   Another upheaval in the workplace took

place after Christopher Sholes invented the typewriter in 1867 and James

Densmore improved and sold it in 1873.  Next to the light bulb, howver,

perhaps the most dramatic invention was the telephone, unveiled by

Alexander Graham Bell and Thomas Watson in 1876.  Although coast-to-

coast phone service did not begin until 1915 and was slow and expensive ,

this invention laid the groundwork for a worldwide communications network.