We recently heard from a long-time listener who couldn't recall if there is a name for the phenomenon he described this way: "You know those three-way mirrors in alcoves of department store dressing rooms? When you peer out of the corner of your eye, your body seems to disappear into a ribbon of ever-smaller reflection of yourself. It reminds me of the way railroad tracks dissolve into the distance…Is there a word for this visual effect?" (来源：英语学习门户网站EnglishCN.com)

We would guess psychologists might have a term for this disappearing self, but our correspondent asked for the name for the visual effect. Since the late 1700s, the place at which a group of receding parallel lines seem to meet when represented in linear perspective has been known as the vanishing point. (来源：英语分类信息 http://fl.englishcn.com)

The especially perspicacious among us may feel compelled to point out the ever-smaller reflections in the three-way-mirror are not parallel to each other; still, the point of identifying perspective, that is, the technique of representing on a plane or curved surface the space relationships of natural objects as they appear to the eye, remains. (来源：英语美食指南 http://food.englishcn.com)

The original sense of perspective, by the way, referred simply to "an optical glass, as a telescope," and piece of perspective to "a picture painted so as to appear distorted or confused except when viewed from a single viewpoint." Those senses are now archaic and obsolete respectively, but perspective survives.