Harris & Ewing Inc. photographed people, events, and architecture, particularly in Washington, D.C., during the period 1905-1945. Photo: Tests of Curtiss Palne for Army, Single Control. Created by Harris & Ewing. Published in 1912.

Fashion models Darien Leigh and Valerie Drew play leap-frog on the beach. 2nd July 1956. (Photo by Harry Kerr). P.S. All pictures are presented in high resolution.

Most people know Nikon as a purveyor of pro and consumer-grade digital cameras. But the company's expertise with optics bleeds over into related markets – it's one of the science community's major suppliers of microscopes. And each year the company asks the community to send it some of their favorite images of tiny objects. A panel of scientists and journalists have chosen the best of this past year's submissions, which Nikon has placed on its Small World site.

Photo: Honorable Mention. “Snow crystal, illuminated with colored lights (5x)”. (Photo by Dr. Kenneth Libbrecht, California Institute of Technology (Caltech), Department of Physics, Pasadena, California, USA)

A silicon rug in the form of Adolph Hitler on display during an exhibition by Israeli artist Boaz Arad, at the Center for Contemporary Art February 22, 2007 in Tel Aviv, Israel. Arad is an Israeli artist who is dealing with the Holocaust in a provocative way. He uses the Holocaust to discuss human evil and contemporary Israel, which he says is torn and crumbling. (Photo by David Silverman/Getty Images)

Masked Guggen music bands parade through the streets on the occasion of the beginning of the Fasnacht Carnival of Lucerne, Switzerland, early 23 February 2017. (Photo by Urs Flueeler/EPA)

A man dressed up as the devil jumps over babies lying on a mattress in the street during “El Colacho”, the “baby jumping festival” in the village of Castrillo de Murcia, near Burgos on June 18, 2017. Baby jumping (El Colacho) is a traditional Spanish practice dating back to 1620 that takes place annually to celebrate the Catholic feast of Corpus Christi. During the act – known as El Salto del Colacho (the devil's jump) or simply El Colacho – men dressed as the Devil jump over babies born in the last twelve months of the year who lie on mattresses in the street. (Photo by Cesar Manso/AFP Photo)

Commuters hang off a local passenger train in the morning in Colombo, Sri Lanka September 8, 2016. (Photo by Dinuka Liyanawatte/Reuters)