Stereoscopic photograph of a bridge and houses at Srinagar in Jammu and Kashmir, taken by James Ricalton in c. 1903, from The Underwood Travel Library: Stereoscopic Views of India. This image is described by Ricalton in 'India Through the Stereoscope' (1907), "The city lies on both sides of us, i.e., on both banks of the Jhelum which follows its course for two miles within city limits and is crossed by seven bridges, all similar to this except one, which is of stone and iron...This quaint bridge is self-explained, hand-made or ax-made, buttressed with interlocked timbers anchored by enormous quantities of stone...We see ice-shields protecting the bridge-piers, and we know therefrom that ice-floes endanger these bridges when winter relaxes its icy grip. We see, too, the gondolas of this Himalayan Venice as they are paddled up and down the stream." This is one of a series of 100 photographs designed to be viewed through a special binocular viewer, producing a 3D effect. The series was sold together with a book of descriptions and a map with precise locations to enable the 'traveller' to imagine that he was touring around India. Stereoscopic cameras, those with two lenses and the ability to take two photographs at the same time, were introduced in the mid 19th century and revolutionised photography. They cut down exposure time and thus allowed for some movement in the image without blurring as subjects were not required to sit for long periods to produce sharp results.