Johns Hopkins, Baltimore merchant & banker, left an estate of $7 million (US$137.3 million in 2014) when he died Christmas Eve 1873 at age 78. His will stipulated that his fortune be used to found two institutions that would bear his name: "Johns Hopkins University" & "The Johns Hopkins Hospital." At that time, Hopkins's gift was the largest philanthropic bequest in United States history. His name was "Johns", no apostrophe, just "Johns."
Johns Hopkins University recently streamlined their logo. Compare this version to the more colorful but visually cluttered original, which also contains elements from the Maryland state flag, globe, book, and shield.