The cover of the March 11, 1986, issue of Eos featured an attractive color world map entitled “Relief of the Surface of the Earth,” published jointly by several agencies. It is stated that the Mercator projection is used, as indeed it appears and is so labeled. In fact, this is not a true Mercator. The detail on the map, as available to the public, deviates from its correct position by as much as 3.2 mm (53 km) at 65°N and S latitude given the printed scale of 1:39,000,000 for the equator. This will not be a problem for many applications of the map, but it can seriously affect attempts to overlay other data on it.