Refracting telescope
Refractors were the earliest type of optical telescope. The first practical refracting telescopes appeared in the Netherlands about 1608, and were credited to three individuals, Hans Lippershey and Zacharias Janssen, spectacle-makers in Middelburg, and Jacob Metius of Alkmaar. Galileo Galilei, happening to be in Venice in about the month of May 1609, heard of the invention and constructed a version of his own. Galileo then communicated the details of his invention to the public, and presented the instrument itself to the Doge Leonardo Donato, sitting in full council.
History of tracheal intubation
While all these surgical advances were taking place, many important developments were also taking place in the science of optics. Many new optical instruments with medical applications were invented during the 19th century. In 1805, a German army surgeon named Philipp von Bozzini (1773–1809) invented a device he called the "lichtleiter" (or light-guiding instrument). This instrument, the ancestor of the modern endoscope, was used to examine the urethra, the human urinary bladder, rectum, oropharynx and nasopharynx. The instrument consisted of a candle within a metal chimney; a mirror on the inside reflected light from the candle through attachments into the relevant body cavity. The practice of gastric endoscopy in humans was pioneered by United States Army surgeon William Beaumont (1785–1853) in 1822 with the cooperation of his patient Alexis St. Martin (1794–1880), a victim of an accidental gunshot wound to the stomach. In 1853, Antonin Jean Desormeaux (1815–1882) of Paris modified Bozzini's lichtleiter such that a mirror would reflect light from a kerosene lamp through a long metal channel. Referring to this instrument as an "endoscope" (he is credited with coining this term), Desormeaux employed it to examine the urinary bladder. However, like Bozzini's lichtleiter, Desormeaux's endoscope was of limited utility due to its propensity to become very hot during use. In 1868, Adolph Kussmaul (1822–1902) of Germany performed the first esophagogastroduodenoscopy (a diagnostic procedure in which an endoscope is used to visualize the esophagus, stomach and duodenum) on a living human. The subject was a sword-swallower, who swallowed a metal tube with a length of 47 centimeters and a diameter of 13 millimeters. On 2 October 1877, Berlin urologist Maximilian Carl-Friedrich Nitze (1848–1906) and Viennese instrument maker Josef Leiter (1830–1892) introduced the first practical cystourethroscope with an electric light source. The instrument's biggest drawback was the tungsten filament incandescent light bulb (invented by Alexander Lodygin, 1847–1923), which became very hot and required a complicated water cooling system. In 1881, Polish physician Jan Mikulicz-Radecki (1850–1905) created the first rigid gastroscope for practical applications.