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Pitcher in a Jam? Call the Weatherman!
Rear Admiral Dan Gallery
April 15, 1957
Now hear this: when the curves don't break or the fast balls sail like toy balloons, don't blame the pitchers. It's probably the air
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April 15, 1957

Pitcher In A Jam? Call The Weatherman!

Now hear this: when the curves don't break or the fast balls sail like toy balloons, don't blame the pitchers. It's probably the air

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Admiral Gallery, commander of the Caribbean Sea Frontier, will be remembered by SPORTS ILLUSTRATED readers for his acerbic analysis of baseball rules in the February 4 issue. Here he applies himself to a different controversy and comes up with some astonishing conclusions.

Connie Mack once said that pitching is between 50% and 90% of a pennant-winning baseball club. You might think, therefore, that the major league clubs would be well aware of all the facts of life about pitching and all the angles that affect it. But they are blissfully ignorant of one of the major facts—namely, that the air around us is even more changeable than the sea and that routine variations in the atmosphere can make Whitey Ford a cousin to a last place club on the same day that they enable a bullpen pitcher to throw a no-hitter at the Yanks.

We are all aware of the daily changes in weather and can feel differences in temperature and humidity. But we can't feel changes in the most important quality of the air from a pitcher's point of view: its density. In fact, most people don't even know what density means. They think the air is dense when it's foggy, although just the opposite is true.

Density means the actual weight of a cubic foot of air, and it depends on the temperature, barometric pressure and relative humidity. Change any one of those factors and you change the density of the air. A good average figure for the density in Chicago during August, for instance, is just under two pounds per cubic yard.

Note that I say "average." A cubic foot of water weighs 62.4 pounds every day in the year unless you freeze it or turn it into steam. But the weight of a cubic foot of air can easily vary by 15% during the baseball season and often changes by 5% from one game to the next.

So what? If it's cold or damp we put on a coat. The barometer changes so slowly that we don't feel any crackling in our ears, as we do in an elevator. We go on about our daily business and nobody knows or cares whether the air he is breathing weighs 1.8 pounds per cubic yard or 2.1 pounds.

But a baseball coming up to the plate at more than 100 feet per second and several hundred revolutions per minute can tell the difference in density right away. When density is high, the ball will dodge coyly under Mickey Mantle's murderous swing, leaving three base runners stranded. If the density is low, the ball spins round and round but can't get its teeth into anything to help it break, so Mickey belts the poor little cripple out of the park. Whenever this happens the pitcher comes in at the end of the inning bellyaching that "the curve hung up"—which, of course, is exactly what happened. But if anybody on the club understood about air density they wouldn't have had a curve ball artist trying to pitch on that particular day.

It is strange that no one has gone into this business of air density yet, because all ballplayers know instinctively that it's air resistance that makes a curve ball break. Everyone who ever played in Denver knows you can't get a good break on a curve ball in the thin air up there at 5,000 feet above sea level, and that batting averages in that league don't mean a thing. The hitters never see anything but fast balls which go a mile if you get any wood on them. Of course, the idea that an invisible, colorless gas like air has density is a rather difficult one to grasp, and I suppose you can't blame the baseball brass for not knowing too much about it. But there are plenty of people in this country who know all about it—aeronautical engineers and fliers. They know because their daily bread and their necks depend on it.

A tremendous amount of money is spent each year on aerodynamic research. There are huge batteries of wind tunnels all over the country running tests on models of planes and missiles to find out how the full-scale jobs will fly. The reason why a plane flies—whether it's an open cockpit sport plane or a supersonic jet interceptor—is the same as the reason why a curve ball breaks. It's the reaction of the air to any object moving through it at high speed.

There are whole libraries full of the technical reports which aeronautical scientists have compiled over the past 50 years. Buried in an obscure corner of these libraries you can find one on the so-called Magnus effect. This tells about the "lift" forces generated by a spinning object with a curved surface moving through the air. It explains why a curve ball breaks and a golf ball hooks or slices. Any pitcher will tell you that the break on his curve ball depends on the speed of the pitch and the amount of spin he puts on it. Most pitchers don't know that it also depends on the density of the air.

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