Amateur Telescope-Making: Popular Astronomy and the Great Depression

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Plate b41215 of Halley’s comet taken on April 21, 1910 from Arequipa, Peru. HCO.

The highly publicized return of Halley’s Comet in 1910 remains one of the most high-profile events of modern astronomy. Stories of the comet circulated the globe in the months and years preceding the comet’s reappearance. Mark Twain, who was born two weeks after the 1835 apparition, famously wrote in his 1909 autobiography that it would be the “greatest disappointment of [his] life” if his death did not coincide once again with the comet’s return. He died the day after its perihelion. The fame of the 1910 visitation caused a heightened degree of panic among the general public both in the United States and abroad, and similarly inspired a number of hoaxes. While the professionalization of astronomical inquiry was on the rise at the turn of the century, the average American had very few opportunities for direct engagement with the science of astronomy. Newspapers and print media controlled the public-facing narrative of the discipline, which all too often meant pseudo-scientific narratives overshadowed methodology and facts.

In 1910, astronomy was both a profession for trained scientists and a more recreational pastime among the educated well-to-do. While popular books like Richard Proctor’s The Expanse of Heaven and Simon Newcomb’s Astronomy for Everybody were relatively popular among the general public, based on the extent of circulation and number of subsequent editions, amateur astronomy in practice was almost exclusively limited to elite, white men. That said, ‘Amateur science’ at turn of the century was less defined in practice and qualification than it is today. Prior to the late 19th century, the distinction between amateur and professional in regards to astronomical study was almost meaningless. In comparison with other scientific disciplines during the transition towards professionalization, astronomers in particular fostered closer relationships between early professional and amateur practitioners. Amateur activity frequently impacted the professional field.

George Ellery Hale, who founded a number of astronomical institutions including the Yerkes Observatory and the Mount Wilson Observatory, was a vocal advocate of amateur astronomy. Edward Pickering, Director of the Harvard College Observatory welcomed amateur participation and supported the founding of the American Association of Variable Star Observers (AAVSO) in 1911. The AAVSO capitalized on amateur supplied data under the supervision of professional astronomers at the H.C.O., and remained headquartered at Harvard for the first forty years of its existence. For comparison, early professional organizations in fields like geology and anthropology explicitly banned amateurs from membership. Amateur participation in astronomy was therefore potentially open to many, but in practice, the number of participants were few.

AAVSO Members c. 1916. Harvard College Observatory.

The discrepancy between public interest and participation was largely a result of financial constraints and the relative scarcity of astronomical instruments. The fine, hand-crafted telescopes in production were expensive and limited in supply. Until the 1920s, telescope making in the United States was limited to a handful of small, often family-owned companies, and even then, the tradition of telescope-making in the U.S. was relatively young. When William Cranch Bond founded the Harvard College Observatory in 1839, there was likely only a few dozen astronomical telescopes in the United States, and nearly all of them imported. The H.C.O.’s first 15-inch Merz and Mahler telescope came from a German manufacturer.

American telescope making began in earnest in the mid-19th century. Amasa Holcomb (1787-1875) was the first significant telescope-maker in the United States, though it’s unlikely his business ever produced more than a few dozen instruments, but he opened the door for an American market. Alvan Clark & Sons, easily the premier telescope manufacturer in the United States from 1860 to 1900, rose to prominence when the outbreak of the Civil War interrupted the order of an 18½-inch refractor. The Clarks sold the telescope, originally intended for the University of Mississippi, to the University of Chicago, and capitalized on the publicity of the wartime sale to bolster their business. By the 1870s, American observatories predominantly housed American-made telescopes. In 1895, Alvan Clark & Sons produced the optics for the world’s largest 40-inch aperture refracting telescope at the Yerkes Observatory, but smaller telescopes of 3 to 6-inch aperture made up the bulk of their sales. These were amateur instruments for amateur observers, but their numbers were still relatively few. The entire estimated production of Alvan Clark & Sons’ amateur telescopes numbered under four hundred instruments. At the height of production (1890-1920), the Clarks only produced 240 complete telescopes, which is an average of 8 telescopes per year. Between 1910 and 1930, relatively small instruments with only a 3-inch aperture could cost from $110 to $150. For comparison, after the introduction of mass-production in 1924, a Model T Ford cost $290.  The commercial market was small and prices were too high for all but the wealthiest or most dedicated amateur observers, but public interest in astronomy was growing. In the decades after the 1910 visitation of Halley’s Comet, a few dedicated hobbyist began to seek out alternative solutions, and amateur-telescope making became an increasingly popular ‘sub-hobby’ among astronomy enthusiasts.

Yerkes Observatory 40-inch Refractor Telescope. c. 1897.

Prior to the 1920s, the availability of quality glass on the open market was a significant obstacle to amateur telescope-makers (self-titled ‘ATMs’). Increased wartime production for military optics resulted in a surplus after the war and optical equipment became more readily available in the open market. The more crucial problems came down to instruction. In October 1910, John Mellish, an amateur astronomer from Wisconsin, published an article on telescope building in Popular Mechanics, but its reach was limited. In October of 1917, C.J. Larson wrote a longer series of detailed articles for the Scientific American Supplement with accompanying illustrations on telescope making, but World War One dominated public (and scientific) discourse that year. Larson’s articles slipped by relatively unnoticed. Then in 1920, a man inspired by Mellish’s 1910 article named Russell W. Porter began a class on amateur telescope-making in Springfield, Vermont.

In the early 1920s, Scientific American went through some editorial changes, which included switching from a weekly to a monthly format. The new policies included an added emphasis on reader feedback and participatory content. Under the direction of new editor Albert Ingalls, the magazine began seeking out and publishing more ‘how to do it’ articles. In the November 1925 issue, Ingalls wrote the lead article on Porter’s Springfield Telescope Makers. The story “The Heavens Declare the Glory of God: How a Group of Enthusiasts Learned to Make Telescopes and Became Amateur Astronomers” was a huge success, and the editorial staff was flooded with requests for more information. In 1926, Ingalls published an expanded series of ‘how to’ articles on telescope-making. At the end of the year, editors combined the articles in a 102-page book. The first printing of Amateur Telescope Making, 3,400 copies in total, sold out in two years, which led to an immediate second edition. The expanded 1928 edition sold out in 1932. The 600 page third edition was published that same year and has remained in print since.

Amateur Telescope Making. Books One – Three.

The “Roaring Twenties” was a decade defined by post-war optimism and opulence that ended with the most severe economic depression of the 20th century. On October 29, 1929, otherwise known as Black Tuesday, the U.S. stock market crashed, effectively erasing billions of dollars of wealth in a single day. Over the next three years, the worldwide GDP fell nearly 15%. In the United States, almost 30,000 business failed, a rate in 1931 which equated to 133 business failures each day. Thousands of banks closed with billions in unreturned deposits. By 1933, unemployment reached 25%. In the midst of the economic crisis, amateur (and professional) astronomy was thriving in the United States in comparison with its European counterparts. Historians have speculated that the extent of unemployment in the U.S. conversely created more free time for hobbies like telescope making, allowing non-professional ventures to flourish. Participants in amateur astronomy clubs quadrupled in the early 1930s when unemployment was at a record high. Ham radio and model airplane building similarly increased in popularity during the depression. In the 1930s, ATMs likely numbered in the thousands, as opposed to the scale of participation in the Cold War Period, but the rise of popular astronomy in the United States is remarkable in the context of the Great Depression. Early hobbyist laid the groundwork for the later counterparts, and opened the door for more diverse participation in the field.


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