 Inspired by Macintosh's report, P. Hex Venn (who was at that time the anesthetic advisor to the British firm Eschmann Brothers & Walsh, Ltd.) set about developing an endotracheal tube introducer based on this concept.Venn's design was accepted in March 1973, and what became known as the Eschmann endotracheal tube introducer went into production later that year.The material of Venn's design was different from that of a gum elastic bougie in that it had two layers