N J Wade

..We here present several early reports on phantom penile sensations, with the intent of showing what had been described and why more than 200 years ago...

..Instruments for investigating binocular vision, like the stereoscope and pseudoscope, were invented before those for binaural hearing, like the stethophone and pseudophone...

..The legacy of Cox's chair, and its related treatment of swinging, are to be found in funfairs throughout the world...

..Although Marshal did not publish his observations during his lifetime, they were assembled by his assistant in 1815. Marshal's descriptions of the brains of hydrophobics and maniacs are worthy of note...

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..Several of these philosophical toys proved to be phenomenally popular, particularly when combined with photography...

..0035 mm), based on the resolution of one minute as the minimum visible. In the same year, Jurin questioned the reliability of such estimates because of variations in visual resolution with different stimuli...

..The autokinetic phenomenon involves the perception of isolated stimuli, and so interpretations in terms of some internal eye movement signals remain sustainable...

..Secondly, attempts to render the acoustic figures visible (on the basis of briefly persisting images) led to the discovery of instruments that could synthesise movement. These two developments are discussed in their historical contexts...

..An armory of devices for examining vision and the eye were to follow later in the century. These transformed the study of vision from an observational to an experimental discipline...

..After providing a brief account of Wells's life, his neglected research on vision is described and assessed...

..Commenting on the case of a white woman, part of whose skin was black, he proposed a process of change that was akin to natural selection. His ideas were acknowledged by Charles Darwin in the fourth edition of On the Origin of Species...

..Once order was established then a range of fascinating phenomena came to light (particularly in vision). Others that had long been known became open to more detailed scrutiny...

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..Visual phenomena could often be displayed on the printed page, although novel instruments expanded the scope of seeing, particularly in the nineteenth century...

..The pattern of development in theories of phantom limbs might provide a model for examining out-of-body experiences (OBEs)...

..The interactions between art and both spatial and motion vision were influenced by instruments invented in the early nineteenth century for manipulating the representation of space and time - the stereoscope and the stroboscopic disc...

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..The history of the search for a sixth sense is outlined, and the evidence adduced to support the divisions is assessed. Behavioral evidence generally has been accorded less weight than that from anatomy and physiology...

..In many ways, Wells's experiments were more sophisticated than those of Purkinje, and he should be recognised as a founder of vestibular research. Possible reasons for the neglect of Wells's work are discussed...

..quot; (John Hunter in a letter to Joseph Banks in 1793, published by Home 1794, page 24)...

..However, the eagerness with which the computer has been adopted by perceptual psychologists is likely to be tempered by a growing awareness of the differences between viewing scenes and simulations of them...

..Thus, both stimulus control and the use of the unbiased observer were employed in eighteenth century experimental studies of vision...

..Despite the neglect of Well's work, he should be considered as laying the foundations for the study of vestibular-visual interaction, even though the function of the vestibular system was not known at that time...

..Theories of accommodation in the seventeenth and eighteenth centuries are briefly reviewed, as is the early history of eye glasses...

..Thus, the MAE occurs as a consequence of adapting restricted retinal regions to motion but it can only be expressed when differentially adapted regions are also tested...

..Brewster's attempts to wrest the invention of the stereoscope from Wheatstone were unsuccessful...

..It is concluded that the linear MAE occurs as a consequence of adapting restricted retinal regions to motion but it can only be expressed when nonadapted regions are also tested...

..In contemporary experimental psychology all these instruments have been replaced by the computer. While it has extended the scope of experiments even further it has introduced a new set of limitations...

..We examine the experiments on binocular visual direction conducted by Wells before Wheatstone, and by Towne and LeConte after him, and discuss the reasons for their neglect...

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..Rather than using the phenomenon of a phantom limb to question the veracity of the senses (as Descartes had done), Porterfield integrated his phantom limb experiences into his general account of sensory function...

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..Demonstrations that readers can perform, and that support this argument, are provided on the Perception website at http://www.perceptionweb.com/perc0102/ono.html...

..We argue that LeConte's lack of knowledge of the German literature on vision research prevented him from considering investigating Wheatstone's experiment with a stereogram having a smaller disparity...

..Nevertheless, Helmholtz's own experiments and new discoveries by others sometimes led him to quite different conclusions...

..The relationship between eye movements and perception, following earlier intuitions by Wells and Breuer, was explored by Dodge, and has been of fundamental importance in the direction of vision research over the last century...

..The point will be made that Helmholtz owed a great debt to Müller, but even from his student days in Berlin he was an independent thinker with his own agenda, and never his strict disciple...

..We compare the historical descriptions with some contemporary research, which indicates how depth and motion perception are dependent on the conditions of stimulation...