The end of the Napoleonic era did not terminate internal strife in France. The successor of Louis XVIII, Charles XI, an ultra-royalist, was overthrown by revolution in 1830 to be replaced by Louis Philippe, who reigned only until 1848 when he too was disposed of by revolt. Actually these "revolutions" were in reality only Paris disorders, which in some other countries could have been kept under manageable proportions by political processes, but not in France. After Louis Philippe, the Second Republic was proclaimed and Louis Napoleon, nephew of Bonaparte, was elected president. He immediately made himself dictator and emperor, so that the Second Empire was thus launched in 1852. As Napoleon III, he tried to follow in his uncle's footsteps, but had not the ability. He wanted a strong Prussia, a powerful Sardinia-Piedmont, with an Italian Federation, which he hoped would be favorable to France. As Napoleon I had sold Louisiana to the United States in 1803 when he desperately needed money, so Napoleon 111 decided on a new venture in America by sending French troops into Mexico to make the Archduke Maximilian of Austria Emperor of Mexico. But the French troops were always somewhat anxious there and when the United States emphasized the Monroe Doctrine after its Civil War, Napoleon III abandoned Maximilian to his fate at the hands of the Mexicans. The second French emperor, himself, ended his career as a prisoner of the Germans in the Franco-German War of 1870, in which France lost Alsace
French imperialism in Africa and the Far East followed, perhaps as an antidote for the loss of Alsace and Lorraine. The French also had a persistent dream of overturning British naval supremacy. Before the War of 1870 they had developed a good start with the development of their mobile, high f ire-power gun and torpedo boats, but then they had to turn their money and energies to the land war with Germany. In 1887 Gustave Zede designed the first practical submarine, although the periscope, which allowed the aiming of torpedoes while submerged, was not developed until after the turn of the century.
In 1893 Schneider-Creusot introduced the famous French 75 millimeter field gun, which revolutionized artillery design. Russia, as France's ally of the moment, purchased many of those guns. (Ref. 55 , 139 , 74 , 8 , 211 , 23 , 279 )
In this century Louis Pasteur made great discoveries in chemistry, biology and medicine and Francois Magendie and his pupil Claude Bernard made great advances in human physiology. Charles Brown-Sequard is sometimes considered the founder of endocrinology and Rene' Laennec, working early in the century is considered one of the great clinicians of all time, best remembered for his invention of the stethoscope. But still French medicine was crude in many ways. Blood letting was still a major treatment, but rather than opening veins, the French started using leeches, importing over 40,000,000 of them in a single year.