Stereoviews are quite easy to recognize, as they consist of two identical images side-by-side. In the event that one of the images has been cropped off, they can usually be recognized by their shape, which is square at the bottom and rounded at the top. Stereoscopic photography came into use around 1855. Photographs were taken in double and then inserted into a special viewing device that would create a three-dimensional image. Stereoviews were quite popular throughout the Victorian Age, particularly from the 1860s through the 1880s. Although still produced during the 1890s and perhaps early 1900s, other, more improved methods of photography became dominant.