Mural

<spoiler> Hint: "People and dates with lasting effect."

The initials on the mural corespond to the names of the inventors:

EW = Eli Whitney invented the cotton gin 1794

HD = Humphrey Davy - Demonstrated electric lamp to the Royal Society - 1806

JW = John Whitehurst - Pulsation Engine (hydraulic pump) - 1722 other possible answer James Watt - Improved steam engine - 1763

BF = Benjamin Franklin - Pointed light rod conductor - 1752

GLL = George Louis Lesage - Used a single wire system to telegraph a message - 1774

LP = Louis pasteur - Process of sterilizing milk - 1862

GS = Glenn T. Seaborg - Synthesis and isolation of the radioactive element plutonium - 1941

GM = Guglielmo Marconi - Radio - 1901

AGB = Alexander Graham Bell - Phonophone - 1880

CM = Cyrus McCormick - Inventor the Reaper - 1809

TE = Thomas Edison - Invented phonograph - 1877

NOTE: The icons that go with the initials are all the same except for GS and AGB which have an identical icon.

shouldn't GS be George Stephenson - 1814 or 1825 - since the image is of the steam locomotive? - Rainaer </spoiler>