Langley, Samuel P.


1875 ALS of the aviation pioneer, 3rd Smithsonian Secretary and noted astronomer, devised precise time standards needed with growth of railroads



Autograph ID: 5211
Condition: Very good
Description: “(1834-1906) US astronomer, physicist, inventor of the bolometer aviation pioneer. An assistant at the Harvard College Observatory, he moved to the US Naval Academy as a professor of mathematics but actually went there to restore the Academy’s small observatory. In 1867, he became director of the Allegheny Observatory and professor of astronomy at the Western University of Pennsylvania (now the University of Pittsburgh), a post he kept to 1891 even while becoming 3rd Secretary of the Smithsonian Institution in 1887. He founded the Smithsonian Astrophysical Observatory. Langley arrived in Pittsburgh in 1867 to be 1st director of the Allegheny Observatory, after the institution had fallen into hard times and given to the Western University of Pennsylvania. The department was in disarray-equipment was broken, there was no library and the building needed repairs. He improved observatory equipment and built additional apparati. One of the new instruments was a small transit telescope used to observe the position of the stars as they cross the celestial meridian. He raised money for the department in large part by distributing standard time to cities and railroads. Until then, correct time was occasionally sent from US observatories for public use. Clocks were manually wound and time was imprecise, exact time not especially necessary until railroad tracks were installed. Trains ran by a published schedule, but scheduling was chaotic. If an engineer and a switch operator’s watches differed by even a minute or two, it could mean disaster. Using astronomical observations obtained from the new telescope, Langley devised a precise time standard – including time zones – called the Allegheny Time System. Initially he broadcast time signals to Allegheny city business and the Pennsylvania Railroad. Eventually, twice a day, Allegheny time signals broadcast the correct time via 4,713 miles of telegraph lines to all railroads in the US & Canada. He used the money from the railroads to finance the observatory. From about 1868, revenues from the Allegheny Time funded the Observatory until the US Naval Observatory provided the signals for free in 1883. He then devoted his time at the Observatory initially in researching the sun. He produced hundreds of drawings of solar phenomena, many of which were the first the world had seen. His 1873 remarkably detailed illustration of a sunspot, observed while using the observatory’s 13-inch Fitz-Clark refractor became a classic. In 1886, Langley received the 1st Henry Draper Medal from the National Academy of Sciences for his contributions to solar physics. He attempted to make a working piloted heavier-than-air aircraft. His models flew, but his 2 attempts at piloted flight were unsuccessful. He began experimenting with rubber band powered models and gliders in 1887. He built a rotating arm (functioning like a wind tunnel) and made larger flying models powered by miniature steam engines. Langley realized that sustained powered flight was possible when he found that a 1 lb. brass plate suspended from the rotating arm by a spring, could be kept aloft by a spring tension of less than 1 oz. His 1st success came on May 6, 1896 when his Number 5 unpiloted model flew nearly 3/4 of a mile after a catapult launch from a boat on the Potomac River, 10 times longer than any previous experiment with a heavier-than-air flying machine, demonstrating that stability and sufficient lift could be achieved in such craft. On Nov. 11 that year, his Number 6 model flew over 5,000’. In 1898, based on the success of his models, Langley received a War Department grant of $50,000 and $20,000 from the Smithsonian to develop a piloted airplane, which he called an “Aerodrome”. He hired Charles M. Manly (1876–1927) as engineer and test pilot. While the full-scale Aerodrome was being designed and built, the internal combustion engine was contracted out to manufacturer Stephen Balzer, the design finished by Manley. This engine had more power than the engine for the Wrights’’ 1st airplane. The piloted machine had wire-braced tandem wings (one behind the other). It had a Pénaud tail for pitch and yaw control but no roll control, depending instead on the dihedral angle of the wings, as did the models, for maintaining roughly level flight. Langley sought safety by practicing in calm air over the Potomac River, which required a catapult for launching. The craft had no landing gear, the plan being to descend into the water after demonstrating flight which if successful would entail a partial, if not total, rebuilding of the machine. He gave up the project after 2 crashes on take-off on Oct. 7 & Dec. 8, 1903. In the 1st attempt, Langley said the wing clipped part of the catapult, leading to a plunge into the river; on the 2nd attempt the craft broke up as it left the catapult. The Aerodrome was modified and flown a few hundred feet by Glenn Curtiss in 1914, as part of his attempt to fight the Wright brothers’ patent, and as an effort by the Smithsonian to rescue Langley’s aeronautical reputation. Nevertheless, courts upheld the patent. However, Curtiss’ flights emboldened the Smithsonian to display the Aerodrome as “the first man-carrying aeroplane in the history of the world capable of sustained free flight”. The Smithsonian action triggered a decades-long feud with Orville Wright. Air and sea craft, facilities, a unit of solar radiation, and an award have been named in Langley’s honor: the Smithsonian Institution Langley Gold Medal; NASA Langley X-43A Hyper-X; NASA Langley Research Center (Hampton, Virginia); Langley Air Force Base; Langley Hall at the University of Pittsburgh; Langley Memorial Aeronautical Laboratory; Langley unit of solar radiation; Mount Langley in the Sierra Nevada. He invented the bolometer, an instrument for measuring infrared radiation, which has enabled scientists to detect a change of temperature of less than 1/100,000 of a degree Celsius. It laid the foundation for the measurements of the amount of solar energy on the Earth. His 1881 paper, “The Bolometer and Radiant Energy”, became a scientific classic. He made one of the 1st attempts to measure the surface temperature of the moon, and his measurement of interference of the infrared radiation by carbon dioxide in Earth’s atmosphere was used by Arrhenius in 1896 to make the 1st calculation of how climate would change from a future doubling of carbon dioxide levels. In 1988, the USPS issued an airmail stamp to honor him.

ALS on 8 ¼ x 5 lined Allegheny Observatory, Allegheny, Pennsylvania engraved letterhead while director, March 3 1875, to “Michaels” (likely Frank Michaels, his godson). Langley meant to see Michaels but could not, and will be in NYC and Philadelphia the next 10 days. He can be reached in care of Dr. Morton of the Stevens Institute, Hoboken, and in Philadelphia at Guys Hotel or through Prof. Barker at Franklin Insitute. Langley hopes to see Michaels if he goes east, and will mail the memoirs of Captain Ricq which he asks Michaels to please return, and sends regards to Mrs. Michaels.

HENRY J. MORTON (1836-1902) Scientist, 1st president of the Stevens Institute of Technology. He became professor of physics and chemistry at the Episcopal Academy of Philadelphia in 1860. In 1863, he delivered lectures on chemistry at the Franklin Institute, those on light attracting attention in the US & Europe. He was a founder of the Philadelphia Dental College in 1863 and its 1st professor of chemistry. In 1867, he became editor of the Franklin Institute Journal. He conducted the photographic branch of the US eclipse expedition to Iowa in 1869, and was a member of the expedition organized by Henry Draper to observe the 29 July 1878 total solar eclipse of at Rawlins, Wyoming. He was awarded Ph.Ds by Dickinson College in 1869 and by Princeton in 1871. In 1874 he was elected to the National Academy of Sciences. Besides writing numerous papers on electricity and fluorescence, he assisted in the preparation of “The Student’s Practical Chemistry” (1868). In 1873 he conducted research on the “Fluorescent and Absorption Spectra of the Uranium Salts,” and also on the like spectra of pyrene, and a new material found by him in some petroleum residues which he named thallene. In 1878, he succeeded to the vacancy on the US Lighthouse Board caused by the death of Joseph Henry, holding the appointment to 1885, conducting investigations on fog signals, electric lighting, fire extinguishers, illuminating buoys, and like subjects, in the annual reports of the Board. In 1870, he was named president of the newly-founded Stevens Institute of Technology, and under his direction the faculty was selected and the course of instruction formed. His management of the Institute made it one of the leading technological schools in the US.

GEORGE F. BARKER (1835–1910) Physician and scientist, successively chemical assistant in Harvard Medical School 1858-59 & 1860–61, professor of chemistry & geology in Wheaton (Ill.) College. In 1864 he became Professor of Natural Science at the Western University of Pennsylvania (now the University of Pittsburgh), where he undertook experiments to produce electric light by passing the current through a resisting filament which he claimed was “the first steady electric light generated in Pittsburgh, if not in the country”. He was professor of physiological chemistry & toxicology at Yale, and professor of physics at the University of Pennsylvania 1879-1900, then emeritus professor. He was president of the American Assn. for the Advancement of Science 1879; president of the American Chemical Society; VP of the American Philosophical Society for 10 years; member of the US Electrical Commission; and for several years associate editor of the American Journal of Science. He wrote a Text-Book of Elementary Chemistry (1870); a Physics (1892); etc.”
Type: Letter

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