Great thinkers through history have written for centuries that there is nothing more wasteful of potential talent than war. Young men and women who might have gone on to do great things are mowed down senselessly in wartime, and what we may have gained is forever lost to speculation. Few embody this more than Henry Moseley, a physicist killed by a sniper at the age of 27 during World War I.
The search for an effective rapid-fire weapon, particularly in the latter 19th century, took on some innovative designs, most of them of dubious battlefield utility and rarely employed. All this changed when the U.S. Army adopted the famed Gatling gun in 1866, which could reliably fire up to 400 rounds a minute and had already proven itself in small quantities during the Civil War. John Gatling -- ironically a physician -- had suddenly made warfare far more deadly.
Depiction of the Battle of Monterrey in September 1846 during the Mexican-American War. (Image date: ca. March 2, 1847.)