Alvin Clark was born on March 8, 1804 and married Maria Pease on March 25, 1824. His first son, George Bassett, was born February 14, 1827, and the second son, Alvin Gram, on July 10, 1832. In 1844, George became interested in grinding and polishing reflectors for telescope mirrors and his father took up the work and aided his son in experimenting with this type of telescope. Taking his fathers advice they abandoned the reflector and began work on refracting lenses. Father and son continued development of optical manufacturing skills over several years and produced the first production achromatic lenses made in the United States.
The Clarks established their company in 1846 and in 1852 the younger brother Alvin Gram, trained as a machinist at the public school of Cambridgport, joined his father and brother in lens production. Among their first objective lenses was a 4.75 inch which Mr. Clark used to discover two new double stars in 1852. In 1853, with a new lens of 7.5 inch aperture he discovered 95 Ceti and reported his discoveries to the Rev. W. R. Dawes, the famous double-star observer of England, who purchased from him this lens and later four others. One of these included an 8 inch objective, which Sir. William Huggins used to make the first visual observations of stellar and nebular spectra. This added to the reputation of quality that Clark Lenses provided the observer.
In 1859 he was a guest of Rev. Dawes in England where he visited the Greenwich Observatory and attended a meeting of the Royal Astronomical Society. It was there that he met Sir John Herschel and Lord Rosse. He sold one equatorial mounting and two objective lenses,one 8 and the other 8.25 inches. The results from the use of these was published by Rev. Dawes in the monthly report of the Royal Astronomical Society. This gave the American Manufacturer a wider international reputation. Rev. Dawes paper is provided below.
From Google Books, "Memoirs of the Royal Astronomical Society, Volume 29, 1861"
(Click on document to read)
Dr. F.A.P. Bernard ordered for the University of Mississippi an 18.5 inch telescope larger than any refractors ever before in service. The delivery was prevented by the civil war and the instrument was sold in Chicago and was afterwards in the charge of S.W. Burnham. This is the lens that the Clarks were testing when Sirus B was discovered in 1862.
The Clarks produced lenses of the highest quality for many years. The elder Clark died on August 19, 1887. He was still active in the business at the time of his death. George Bassett died on January 2, 1892, and Alvin Gram died on June 9, 1897.
Alvin Gram, was also a successful observer of astronomical phenomena and discovered 14 double stars, among them the companion of Sirus. He traveled world wide observing eclipses of the sun, and the 1869 transit of Venus. He completed a 30 inch objective lens for the government of Russia, a 36 for the Lick Observatory, 26 for the Washington Naval Observatory, 26 for Leander J. McCormick of Chicago for the University of Virginia. In May of 1897 he delivered the 41.5 to the Yerkes Observatory, Lake Geneva, Wisconsin, the lens for the most powerful refracting telescope in America. Due to the extreme size of the lens blanks, it was an arduous process to secure glass of the quality required. This objective lens cost three years of labor with two assistants. The last survivor of the family of famous lens makers was in failing health as he supervised the installation and died just a month after this delivery.
The company's trained and dedicated work force, under the guidance of a 27 year associate of the Clarks, Optician - Carl Lundun, continued to manufacture unsurpassed optics, under the Alvin Clark & Sons name. The company was purchased in 1933 bringing an end to a great chapter of astronomical history.
Clear Sky - Rich
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