The author's assessment of the cartographers' response to Peters is that it was

mistaken about the mathematics of equal-area projections.

driven mainly by professional resentment of an outsider.

effective in removing the Peters map from classroom use.

accurate in each of its claims yet inattentive to what gave the campaign its force.

The passage presents the Mercator projection's enlargement of high latitudes as

an error traceable to the limits of sixteenth-century surveying.

a defect that later conformal projections were able to correct.

the necessary cost of the property that made the chart useful at sea.

a smaller distortion than the one equal-area projections introduce.

Which of the following inferences does the author explicitly reject?

That because every projection distorts, no projection can fairly be criticized for its distortions.

That because every projection distorts, the choice among them carries consequences.

That because a projection can be assessed against a purpose, some choices are better than others.

That because a default image teaches, the map most often displayed deserves scrutiny.

Which of the following, if true, would most weaken the author's claim that the Mercator's role as a default image was worth objecting to?

Sixteenth-century navigators had no alternative conformal chart available to them.

People who see world maps regularly estimate the relative areas of continents no more accurately than people who do not.

Several equal-area projections distort the shapes of landmasses near the poles severely.

The projection Peters presented had been published by James Gall more than a century earlier.

The author's conclusion depends on the assumption that

most readers of maps are unaware that every projection distorts.

navigation is no longer an important use to which maps are put.

equal-area projections are the appropriate choice for classroom display.

the distortions of a projection can be quantified and compared.

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The Map That Cannot Be Honest

PRACTICE

100:00+4 −1MCQ Single Answer

Reading Passage

The first thing to understand about map projections is that their central difficulty is mathematical rather than political. A sphere and a plane have different intrinsic curvature, and Gauss proved that no transformation between them can preserve distances everywhere; the surface of the earth cannot be laid flat without being stretched or torn. Every projection therefore preserves some properties and sacrifices others. Mercator's, published in 1569, preserves angles: a straight line drawn on the chart is a line of constant compass bearing, which is precisely what a helmsman with no other instrument needs. The price of that property is area. The stretching required to keep angles true grows without limit toward the poles, and on a Mercator chart Greenland is made to rival Africa, which is fourteen times its size. In 1973 Arno Peters presented an equal-area world map and attacked the Mercator as an artefact of European self-regard, a chart that shrank the tropics and swelled the latitudes of the colonizing powers. Development agencies took the map up, and it entered classrooms and aid literature over the following decade. Cartographers replied with unusual unanimity and unusual irritation. The projection was not Peters's invention, having been published by James Gall more than a century earlier; his historical claims about Mercator's motives were unsupported; and the fidelity of area was purchased at the cost of shapes so elongated that the continents appeared to have been hung out to dry. Every one of these objections was correct, and together they missed the thing that gave the campaign its force. A projection devised for navigation had become the default picture of the world, hanging on classroom walls where no one was steering anything, and defaults do their teaching quietly. If all projections distort, it is tempting to conclude that all are equally arbitrary and that criticism of any of them is idle. That inference does not hold. Distortion is unavoidable, but it is not unconstrained: it can be quantified, mapped across the surface, and set against the use to which a particular map is put. The Mercator is very nearly the ideal chart for a navigator and an indefensible choice for a wall display of the relative size of nations. The useful question was never which map tells the truth, since none can. It is which distortion a given purpose can afford to accept. On that reading the honest map is not the undistorted one, which does not exist, but the one whose distortions have been chosen for a job and admitted to the reader.

The primary purpose of the passage is to