In the production of vowels the vocal organs do not come very close together to form obstructions to the air stream so it is difficult to have a clear sensation of the whereabouts of the vocal organs Therefore methods for describing vowels on some basis other than articulatory were thought in 19th century. Eventually, it occurred to phoneticians that it would be a way out to establish, on an auditory basis a set of arbitrary reference points- cardinal vowels so that a given vowel could be described in terms of its relation to them• In the production of vowels, the vocal organs do not come very close together to form obstructions to the air stream, so it is difficult to have a clear sensation of the whereabouts of the vocal organs. Therefore methods for describing vowels on some basis other than articulatory were thought in 19th century. Eventually, it occurred to phoneticians that it would be a way out to establish, on an auditory basis, a set of arbitrary reference points – cardinal vowels, so that a given vowel could be described in terms of its relation to them