Looming is a term found in the study of perception, as it relates directly to psychology. Looming refers to the rapid expansion in the size of any given image. As the image becomes increasingly large on the perceiver's retina, i.e., when an object looms, there is an automatic physiological response to perceive the object as an approaching object or surface, instead of one that is stationary or receding. The type of mirage described as looming, in which distant objects appear much nearer than they actually are, is explained in the same way as the image of the ship, except that the image is not inverted; the density variations may also act as a magnifying glass. Origins of the term may be traced back to industrial London of the 1760's, where the advent of the Automated Looms whirring in the background made for a "looming" presence in factories.