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Images of snow crystals

Image credit: SCHWERDTFEGER LIBRARY, UW-MADISON

No two alike

For decades, Wilson Alwyn Bentley took detailed photographs of snow crystals, effectively pioneering photomicrography. Today, his iconic images are a ubiquitous aspect of winter—thanks in part to a Johns Hopkins–trained physicist.

At an auction of photography at Swann Galleries in New York City last spring, an album of 51 images of snow crystals sold for $22,500 to an anonymous dealer bidding by phone. The black-and-white prints of these intricate starlike crystals, each approximately 3 square inches, had been made at the turn of the 20th century by Wilson Alwyn Bentley of Jericho, Vermont, whose work was introduced to the collector market as a folk artist in the 1990s.

Yet the man, who today is better known as "Snowflake Bentley," considered himself foremost a scientist, not an artist, and it was a group of his scientist colleagues, particularly a Johns Hopkins–trained physicist, who championed him and helped bring his work to a wide audience. Given his artful images of these dazzling, jewellike, ephemeral phenomena of nature, maybe it's best to think of him as part artist, part scientist—even though that hybridity has sometimes gotten him into a bit of trouble.

We learn as kids that no two snowflakes are alike. What we aren't told is that a snowflake is composed of dozens, sometimes hundreds, of snow crystals that coalesce in tufts or clumps as they tumble from the clouds. Snow crystals, not snowflakes, are the featured symbols on winter holiday decorations. Technicalities aside, it was Bentley, born in 1865 toward the end of the Civil War, who is acknowledged to be the first person to proclaim publicly each snow crystal's uniqueness.

He saw the "proof" in his photographs. Bentley's photos of snow crystals are celebrated not only because of their astonishing beauty but because they were the world's first. Their creation with rudimentary equipment in an unheated shed on a remote New England dairy farm—without electricity or running water—was an extraordinary feat. And then there is the obsessive nature of their maker's enterprise.

Wilson Bentley

Image caption: Wilson Bentley photographing snowflakes on his farm in Vermont.

Image credit: Wikimedia Commons

The art world, for its part, has made much of how this presumed eccentric became so obsessed with photographing snowflakes that he did so for five decades, never stopping until his death. As he himself wrote toward the end of his life, "[I'm] amazed and thrilled at their matchless loveliness, [and] the work soon became so all-absorbing that I have continued it with undiminished enthusiasm all these years."

Bentley's obsession began when he was a freshman in high school. That year his mother, a former schoolteacher, bought him a microscope. She had previously home-schooled him, so it's possible the transition to regular school was too much for him and he needed an escape into a world of his own. In any case, seeing magnified snow crystals sent him on a quest to capture their evanescence in some kind of permanent form. First, he tried drawing his subjects while holding his breath so its warmth wouldn't melt them away too quickly. Frustrated by those imprecise results, he turned to photography, learning about it from a local man who, after establishing a studio in Connecticut, returned to Jericho to visit. Bentley produced his first successful image at age 19 in 1885.

To make his negatives, he used the large bellows camera that his obliging parents had bought for him. To this, he coupled his microscope, effectively pioneering not only snow crystallography but photomicrography, too. All winter, during Jericho's frequent snowstorms, he let snow fall onto a board he held skyward. He next isolated a few crystals before he ultimately selected the most exquisite example and transferred it to a glass microscope slide. For this delicate operation, he used such tools as a turkey wing feather.

He worked inside a shed on his family's farm where the temperature, of course, had to be below freezing. After developing the negatives, he needed to execute one more vital step. Applying a photography technique known as blocking or blocking out, Bentley spent hours using an etching knife and other sharp-pointed tools to scrape away the dark emulsion around the snow crystal's edges in order to produce a single aesthetically pleasing image. The artistic side of Bentley didn't override the scientific one, however. He used a duplicate negative for this final process, always retaining the original as documentary evidence.

Composite image of three snow crystals

Image credit: University of Wisconsin Madison Collection

Initially, the art world portrayed Bentley as an "outsider artist," a term used to denote artistically naive people without formal training or much contact with other artists. And while he never strayed far from Jericho, and apparently didn't engage with an artistic community, he thoroughly involved himself with the national scientific community in meaningful ways. In 1898, when he was 33, he began publishing articles on snow crystals, ice crystals, and frost in peer-reviewed scientific journals. He later joined professional organizations, including the American Meteorological Society. Indeed, the scientific value of his snow crystal photographs, each one meticulously numbered and dated in records he kept, was immeasurably enhanced by his detailed notes on meteorological observations recorded at the moment of each image's capture, i.e., temperature, wind force and direction, cloud conditions, and changes to the character of the snow crystals as the storm progressed. Far from being reclusive, Bentley, by one account published in the Bulletin of the American Meteorological Society in 1931—the year he died at age 66—was "known to every scientific student of weather in the world."

In 1898, the same year Bentley started publishing, the Harvard Mineralogical Museum (now the Mineralogical & Geological Museum at Harvard University) learned of his work and bought 400 prints, lauding them as "a large and perfect collection which may justly be called a monument to the patience, skill, and enthusiasm of the maker." Six years later, in 1904, the Smithsonian Institution bought and archived 500 more. On that basis alone, Bentley would have enjoyed some notability. But one more component was necessary before he achieved the kind of long-lasting celebrity that has spawned a full-length biography, a couple of children's books, a children's film, a permanent museum exhibition in his Jericho hometown, and the high prices that auction houses and art galleries are able to get for his prints—originally sold by Bentley for 30 cents or less. That component was Bentley's one book, titled simply Snow Crystals and published in 1931 with the help of William Jackson Humphreys, who received his PhD in physics at Johns Hopkins in 1897.

Three years Bentley's senior, Humphreys was born in 1862, in Gap Mills, West Virginia. Humphreys began his education in a one-room schoolhouse in Gap Mills, where the school year ran only from December to March, "and for many of the larger boys, not even that much," Humphreys wrote in his self-published autobiography, Of Me, "for they had both late fall work and early spring work to do on the farms." At home, a log cabin with lean-to attached, there were no books, except the Bible, but he had an uncle who was a professor of Greek at Vanderbilt University. It was he who sent his 14-year-old nephew a small book on physics and one on plane geometry, and changed the boy's life. Enthralled, Humphreys quickly gained a reputation for "studiousness." That same year, the family moved to Pomeroy, Ohio, the compelling reason being, in Humphreys' words, "the assurance it gave of far greater school facilities than were available where we had been living." In Pomeroy, Humphreys completed all four years of high school in one. He was awarded a scholarship to Washington and Lee University. The valedictorian of his class, he went on to the University of Virginia, after which Johns Hopkins offered him three years of paid study. He turned down a similar offer from Harvard.

William Jackson Humphreys

Image caption: William Jackson Humphreys

Image credit: Wikimedia Commons

Humphreys' doctoral dissertation, "The Pressure Shift of Spectrum Lines," grew out of spectroscopic work he did for Johns Hopkins' brilliant, idiosyncratic, and revered physics professor Henry Augustus Rowland—not that he offered Humphreys much direction. "He never gave anyone detailed instructions as to how to conduct an experiment," Humphreys recounts in Of Me. "In fact, the advice he commonly gave to one in despair who asked him for help was that which he himself followed: 'Do something to it, man, do something to it, and something'll happen.'" For the record, Humphreys wrote in Of Me that he credits a suggestion made by physicist Joseph Sweetman Ames of Johns Hopkins, not Rowland, as "an exceedingly important determinant" of his destiny. He says it was Ames' idea that Humphreys and John Frederick "Fred" Mohler, another physics graduate student under Ames' charge, "compare the arc spectra of metals produced under increased atmospheric pressure with those produced under normal pressure." According to Humphreys, this led each man to his PhD thesis. It also led to an invitation for Humphreys to attend the dedication of the new Yerkes Observatory in Williams Bay, Wisconsin, in 1897, which in turn led to the chance to travel to Griffin, Georgia, to observe the total solar eclipse in 1900; to go on the Naval Observatory's eclipse expedition to Sumatra in 1901; and to the offer of a job in 1905 that would determine his career.

Humphreys was hired that year as supervising director of the U.S. Weather Bureau's newly founded research station at Mount Weather, Virginia, on the crest of the Blue Ridge Mountains. The only trained physicist among the bureau's meteorologists, Humphreys was transferred in 1908 from Mount Weather to bureau headquarters in Washington.

As one of the most respected meteorological writers in the America of his day, Humphreys published many books, including ones for general audiences. His best known is Physics of the Air, originally issued by Philadelphia's Franklin Institute in 1920. He had lots to say about climate change, attributing it in part to volcanic dust, along with such less timely topics as types of lightning (streak, rocket, ball, etc.), the velocity of rainfall, rainbows, whirlwinds, cyclones, sunspots, and the shadow bands seen during solar eclipses. He also knew his snow.

Where and how Humphreys first encountered Bentley, however, is unknown. We do know that both men were among the first to be elected in 1920 as fellows of the American Meteorological Society. And Humphreys obviously respected Bentley's work since he referred to it in his writings. At some point, the two agreed to make a book together. Fundraising was required to publish Snow Crystals. After Humphreys made an impassioned speech at an American Meteorological Society meeting, depicting Bentley as a "rare and kindly genius," he secured from donors the $1,800 required by McGraw-Hill as a guarantee.

Composite image of three snow crystals

Image credit: UNIVERSITY OF WISCONSIN MADISON COLLECTION

Snow Crystals came out in a small edition in 1931. It consists of more than 2,000 of Bentley's photos, selected by Humphreys from an oeuvre of over 5,000, along with some of frost, glaze, dew on vegetation and spider webs, sleet, and soft hail. Humphreys' introduction marvels that "no two [snow crystals] are alike, yet all are based on a common hexagon," and goes on to cover snow crystal classification, the fundamentals of crystallography, and Bentley's photographic techniques. There are also brief discussions of the nature and cause of ice flowers, windowpane frost, sleet, and other winter weather elements. But just as important was Humphreys' role in shepherding the book through the publishing process. Both men's names, rightly, appeared on the cover of the first edition as co-authors. (Humphreys assigned his royalties to the American Meteorological Society.) And both men were credited again when the book was reissued in 1962 by Dover Publications. Snow Crystals has remained in print ever since, reintroducing Bentley's work to generation after generation.

Sheldon Izen, of Seattle, is a collector who became smitten with Bentley in the 1970s when he found a copy of the Dover reprint in a used bookstore. He has since amassed numerous Bentley prints. Izen also has original photos by Bentley of himself and of his family's Jericho farmhouse, and a publicity photo showing Humphreys with one of the first copies of Snow Crystals. Izen, who characterized the Dover reprint as "ubiquitous," is proud of having acquired his own copy of the scarce first edition. "I don't think we would be sitting here talking about Bentley if the book hadn't been published," he says.

To be romanticized, mythologized—and occasionally infantilized—are often the wages of celebrity. On the evidence of the children's books and film and some of the art world verbiage, Bentley has paid them. He has even been vilified, for his work methods. The trouble arose when a Bentley contemporary, German meteorologist Gustav Hellmann, claimed that Bentley's blocking-out process was a falsification, making snow crystals appear more perfect than they actually are. Hellmann's photographer, Richard Neuhauss, had made snow crystal microphotographs. Prints made from them were published in Hellmann's Schneekristalle in 1893—and none was as beautiful as any of Bentley's. By way of defense, Bentley cryptically wrote: "A true scientist wishes above all to have his photographs as true to nature as possible, and if retouching will help in this respect, then it is fully justified." Perhaps "retouching" was the wrong word choice. In the opinion of Daile Kaplan, longtime director of the photography department at Swann Galleries, "The fact that Bentley was challenged by Mr. Hellmann is not surprising. After all, casting aspersions is an age-old tactic for achieving dominance." Nonetheless, the controversy is resurrected now and again, as it was on an episode of Radiolab, first aired in 2012 and again in 2019, while Swann was doing publicity around its offer of the Bentley album.

Kenneth Libbrecht, a professor of physics at Caltech, was featured on the same show. Hyperbolically introduced as "the world snowflake expert," he studies the molecular dynamics of crystal growth, especially how ice crystals grow from water vapor. More significantly, he makes his own photomicrographs of snow crystals as a hobby. By his count, he has made 10,000, choice selections of which have appeared in his many published books. He was not asked about the Hellmann claim on the radio show but has a strong opinion about it. In fact, a few years ago, he battled the National Science Foundation over it.

Reached by phone in his Pasadena lab, Libbrecht relates the story. "The NSF funded a researcher in Utah, who set up a camera so it would automatically photograph snowflakes. Forget ten thousand; he took hundreds of thousands of images. And the first thing you notice is that there aren't very many attractive ones." The narration of a 2015 video resulting from that research, by atmospheric scientist Tim Garrett and engineer Cale Fallgatter, referenced Bentley, making the old claim that he had doctored his photographs. Libbrecht complained loudly to the NSF.

"It made him sound like a fraud. I said, 'You can't do this. Bentley is a folk hero, and you've got it all wrong. He didn't make this stuff up. He just selected the very best ones.'" As a result of Libbrecht's appeal, the NSF acknowledges, it changed the video's narration. "It was the same footage, but they changed the voice-over," Libbrecht says. "They corrected their error and didn't make Bentley sound like a villain anymore."

Perhaps Hellmann and others who perpetuate the controversy can be forgiven. No two snowflakes are alike, everyone agrees, but it doesn't naturally follow that all snowflakes are equal. "There's a little secret that Bentley knew and that I know," Libbrecht says. "Ninety-nine point nine percent of snow crystals are not worth photographing. You could easily look at thousands and thousands of them before you pick one to photograph." Libbrecht and others who share his hobby of photographing snow crystals "are always talking about that one good storm," he says. "'Oh, man. It was just perfect for three solid hours. It happens maybe once a winter, often in the middle of the night.'" It was suggested to Libbrecht that he and his compatriots sound like surfers looking for the perfect wave.

Another little secret shared by Libbrecht is this. "If the clouds are really high in the sky, that means you're not going to get anything really good." That's because the final shape of a snow crystal depends on the type of journey it has made on its way down to Earth, and the longer the journey, the greater the chance the snow crystal will be damaged. "The best days are when the clouds are just hanging over your head." It's also true, says Libbrecht, that some places on Earth produce more-photogenic snow crystals than others. His "personal favorite" is the town of Cochran in northern Ontario. Another good prospect is Hokkaido, Japan, where Ukichiro Nakaya of Hokkaido University started his research of snow crystals in 1932 after reading Bentley and Humphreys' book. A third, as it turns out, is the environs of Jericho, Vermont.

Bentley died in Jericho on December 23, 1931. Humphreys wrote his obituary for the magazine Science, concluding it by saying: "Thus the drama ends of the kindly 'Snowflake Man' of Jericho, to whose honored doorstep, however secluded and humble, all the world had worn a path in recognition of true worth." When he wrote Of Me, published in 1947, Humphreys took the opportunity to briefly memorialize him again. "Bentley was well and gloriously happy when the first copies of [Snow Crystals] ... were delivered to him, but died a few days thereafter." Much has been made of the irony that Bentley's cause of death was the pneumonia he contracted after walking home 6 miles through a blizzard, but he probably walked through many a blizzard in a town where the average snowfall is nearly 100 inches annually. That just happened to be the terminal one.

A perhaps more poignant irony is that Dover's latest iteration of Snow Crystals, issued in 2000 and titled Snowflakes in Photographs—technically inaccurate but arguably more enticing—has omitted the name "W.J. Humphreys" from its cover. What's more, the comprehensive introduction by Humphreys has been eliminated. In its place is a short essay by Bentley originally published in 1922 by Popular Mechanics. The man who helped secure Bentley's wide and enduring recognition has, to use a contemporary phrase, been Photoshopped out. What can't be denied is that, thanks to Humphreys the weatherman, we have the Snowflake Man's now vintage work easily to hand.

Jeanne Schinto has been an independent writer since 1973.