Milan. The Italian flag flies over the City Hall. Three hundred patriots (or rebels, depending on your side) are barricaded inside. Only about fifty of them have any kind of weapon. The Austrians are preparing to storm the City Hall. A heroic yet reckless charge attempts to stop them. It is led by the meek Professor Paolo Boselli, founder and director of the Institute on Via Bossi, where Milan’s finest youth studies. Boselli and those following him are impaled by bayonets. No one dares leave the City Hall. Eventually, they all surrender to the Austrian assault. Only Antonio Oliva manages to escape. But the situation has already worsened: around thirty Milanese have already died.

In Germany, the uprisings of 1848 failed, with effects that would ultimately have proved catastrophic. Conservative politicians like Otto von Bismarck consolidated their power in Prussia and created an openly militaristic state that, as early as 1850, began preparing for war against France. The French tactic of preventing German unification at all costs backfired, only strengthening German nationalist sentiment. Prussia heavily defeated Austria in 1866 and created the North German Confederation, annexing several states previously under Austrian influence. In 1870, Prime Minister Bismarck provoked France into declaring war on Prussia. The Franco-Prussian War was brief and brutal, with the Prussians defeating the French at Sedan, Napoleon III being taken prisoner and forced to abdicate, Paris being besieged, and 200,000 French soldiers killed. King Wilhelm becomes Kaiser Wilhelm I, and German reunification is completed, forged with blood and iron. The price will be the disastrous first half of the 20th century.

United States. Secretary of State Buchanan delivers to President Polk the peace treaty with Mexico negotiated by clerk Nicholas Trist. Trist had skillfully negotiated the treaty, taking advantage of a favorable economic climate and obtaining California, Arizona, and New Mexico for the United States. Polk, however, is dissatisfied because he also wanted Baja California, and Trist is promptly fired, ending his career; he is also denied his back pay, which will not be paid until decades later.

The Grand Duke of Tuscany grants the constitution

The reactionary King of the Two Sicilies, Ferdinand II, granted the Constitution and the election of a parliament. Other European sovereigns would follow suit, granting constitutions modeled on the French one. Only Lombardy-Venetia, Parma, and Modena remained without a constitution in Italy.

Milan, Austro-Hungarian Empire. The tobacco issue erupts: the imperial administration raises the tax on smoking (one of the most lucrative), and the Milanese abstain in protest. In response, imperial soldiers receive double rations of cigarettes and cigars and are sent to show off in the city. An episode that seems minor, but demonstrates an unbridgeable rift between the Austrian administration and the Milanese people. Almost martial legislation is passed, and brutal acts by police and soldiers will transform antipathy into hatred within weeks.

Galleria, Milan. Appellate Councilor Manganini, often criticized for his pro-Austrian stance, attempts to restrain three drunken soldiers who are beating a victim. He is killed with two saber blows to the head. The owner of the nearby bookstore and his wife are stabbed, and a customer is injured, the shelves destroyed. On Corso di Porta Comasina (now Porta Garibaldi), a wine merchant has his hand amputated, and his daughter is kidnapped and disappeared. At the Osteria della Foppa, a customer is killed, two women are injured, and a child has his arm amputated. Workers at the famous Sala carriage company are attacked, and only seven of the 18 survive. Official figures are conservative, putting the total at six dead and about fifty injured, but popular rumors suggest much higher figures. The conflict escalates, eventually erupting into war in the streets of Milan.

Lincoln was elected to the House of Representatives for a term. He was subsequently unsuccessful in re-election, so he returned to his work as a country lawyer in Illinois.

Milan. Cardinal Romilli, newly appointed by Pope Pius IX, at a time when the pope’s moves favored Italian patriotism, was greeted with great celebrations, and graffiti insulting Austria appeared on the walls. The Habsburg police chief, Torresani, dispatched Hungarian dragoons from the archbishop’s palace. Shouts of “Long live Italy!” prompted the Magyar cavalry to charge the crowd ferociously. Many were injured, and one Milanese citizen died. Conflict had broken out between Milan and the Austro-Hungarian Empire, of which it was a part.

German Krupp manufactures the first cast steel cannon

Turin chemist Ascanio Sobrero, by dripping glycerin (or glycerin—easily obtained from animal fat) into a cooled mixture of sulfuric and nitric acid, and pouring the resulting solution into water, discovered (or invented) nitroglycerin. Then (perhaps unthinkable today) he tasted the resulting compound and noted that even without swallowing, even contact with the tongue caused a severe headache with throbbing and severe weakness in the limbs. It was later discovered that this was due to the dilation of blood vessels, and nitroglycerin was prescribed for angina pectoris. Today we know that the effect is actually due to simple nitric oxide (NO), and research in this field also led to the development of the drug Viagra, which also relies on the vasodilatory effect of nitric oxide. Alfred Nobel’s idea in Stockholm in 1833, however, was to use a small amount of gunpowder to cause the explosion of a large quantity of nitroglycerin. But Nobel also had to try to avoid unwanted explosions. To do this, he used a diatomaceous earth based on Kieselguhr (diatomite—a porous rock made from diatom shells) to dilute the nitroglycerin. In 1867, Nobel & Company began shipping and selling dynamite around the world.

The English company Fry & Sons creates the first chocolate bars.

Felix Mendelssohn Bartholdy, author of Lauda Sion, dies

Boston dentist, William Morton, demonstrated that ether could induce narcosis, a temporary state of unconsciousness, very useful in surgical procedures. Another substance used for the same purpose was chloroform, an experiment demonstrated by James Young Simpson in November 1847. It has been estimated that during the American Civil War, approximately seven thousand surgical operations were performed on battlefield wounded anesthetized with chloroform, with fewer than 40 deaths due to the use of the anesthetic. In 1853, Queen Victoria gave birth with the aid of chloroform as an anesthetic.

The first satellite of the planet Neptune (itself discovered only a few days earlier) is discovered. For over a century, the satellite will be called “Neptune’s satellite” (a distinction surpassed only by our only moon, simply called “Moon”), until the discovery of Nereid, Neptune’s second satellite. After that, the first will be named Triton and will be visited by Voyager 2, which will photograph spectacular geysers.

The Berlin Observatory consciously and unmistakably sighted the planet Neptune for the first time, where Adams and Le Verrier had indicated it, applying the analysis of Uranus’s orbital perturbations as per Laplace’s vision. In reality, the planet had already been sighted, unconsciously, previously, by Galileo Galilei on December 28, 1612, and on January 27, 1613.

Battle of Monterrey, Mexico. After three days of battle, American General Taylor defeats the Mexicans and captures the city. Taylor’s forces include the Mississippi Rifles Battalion, commanded by Colonel Jefferson Davis (future president of the secessionist Confederate States of America), who was married to Taylor’s daughter for three months before she died of malaria at age 21.

The Sardinian Army was the first to adopt a rifled cannon designed by Cavalli. The weapon, which used a technology—rifling—that was still immature, proved imperfect and was discarded.

The United States Senate declares war on Mexico.

The United States, under the control of the Democratic Party, resolves the issue of Oregon’s northern border, set at the 49th parallel, with a treaty with Great Britain. In the northern United States, there was strong expectation that it would be set much further north: at 54.40. Disappointment was great, and it turned to anger when Southern interests were instead fully protected in the case of the Union’s southern borders, a case that would ultimately lead to war and victory against Mexico, with the annexation of California, Arizona, New Mexico, and Texas. Immediately thereafter, the question of extending slavery to the newly annexed states would erupt, a question strongly opposed by the North and strongly supported by the South. This would be just another of the many factors that, accumulating, would lead to the American Civil War.

United States. President Polk reveals his intentions regarding the war with Mexico to the secretaries of the State Department: to secure for the United States the territories of California, Arizona, and New Mexico.

French mathematician Joseph Bertrand ventured that if you take a prime number, say 1009, and continue counting until you reach double the prime number, you are guaranteed to encounter at least one prime number along the way. This, which became known as Bertrand’s Postulate, would only be proven seven years later by Russian mathematician Paphnutij Chebyshev.