Stereoscopic photograph of a ghat on the Hooghly River near Howrah Bridge at Calcutta in West Bengal, 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), "There are many bathing places along the Hooghly in this vicinity. There are at least seven beyond this on the same bank, and probably as many more in the opposite direction. The next bathing ghat beyond this is where you see those buildings extending towards the river...On certain festal days a much greater number would be found here; at such a time the streets leading towards the ghats are lined with bathers going and returning and carrying chatties [bowls] and other articles of the bath." This is one of a series of 100 photographs, designed to be viewed through a special binocular viewer producing a 3D effect, which were sold together with a book of descriptions and a map. 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.