Template:On This Day (nonfiction)/April 18
1796: Physicist Johan Carl Wilcke dies. Wilcke invented the electrophorus, and calculated the latent heat of ice.
1873: Chemist and academic Justus von Liebig dies. Von Liebeg made pioneering contributions to organic chemistry, especially agricultural and biological chemistry; he is known as the "Father of the fertilizer industry".
1945: Electrical engineer and physicist John Ambrose Fleming dies. Fleming invented the thermionic valve, also known as the vacuum tube.
1955: Physicist, engineer, and academic Albert Einstein dies. Einstein developed the theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics).
2011: Mathematician Curt Meyer dies. Meyer made notable contributions to number theory, including an alternative solution to the class number 1 problem, building on the original Stark–Heegner theorem.
