"Isaac Newton and His Contemporary Christiaan Huygens Argued the Toss Over it Back in the 17th Century" (September 21, 2004)

    So writes Michael Hopkin in the September 20^th news@nature.com. What was being argued? "While Newton was writing his Principia Mathematica... he thought that an object's speed through a fluid would depend on its viscosity, whereas Huygens thought it would not. In the end, Newton included both versions in his text.

Now Edward Cussler of the University of Minnesota and his student Brian Gettelfinger, a competitive swimmer who nearly made the US Olympic team, took according to Hopkin, "more than 300 kilograms of guar gum, an edible thickening agent found in salad dressings, ice cream and shampoo, and dumped it into a 25-metre swimming pool, creating a gloopy liquid twice as thick as water. 'It looked like snot,' says Cussler." Then 16 recreational and competitive swimmers were asked to swim both in standard water and the mixture and as reported in the American Institute of Chemistry and Engineering Journal whatever strokes were used, the swimmers' times differed by no more than 4%, with neither water nor syrup producing consistently faster times.

And Cussler told Hopkin, "[H]is quest for an answer made him something of a celebrity on campus. 'The whole university was arguing about it,' he recalls. 'It was absolutely hilarious.'

As Julius Sumner Miller would have asked some forty years ago, "Why is it so?"

According to Cussler, while you experience more viscous drag, i.e. friction, from your movement through the mixture, you also generate more forward force from every stroke and the two effects cancel each other out.

But the conditions have to be right for that to be the case and as it happens the human body's shape and size meet the criteria. Hopkin concludes:

for humans, speed depends not on what you swim in, but on what shape you are. Once the effects on thrust and friction have been cancelled out, the predominant force that remains is 'form drag'. This is due to the frontal area presented by a body - try running with a large newspaper held in front of you and see how much more difficult it is.

So the perfect swimmer, whether in water or syrup, has powerful muscles but a narrow frontal profile. "The best swimmer should have the body of a snake and the arms of a gorilla," recommends Cussler.

Whether there are any analogous lessons for the rest of us who spend much of our time trying to navigate through the sort of prose discussed by Don Watson in his book Death Sentence may be worth cogitating over.

Watson's final example taken from the Federal Government's Department of Finance:

Given the within year and budget time flexibility accorded to the science agencies in the determination of resource allocation from within their global budget, a multi-parameter approach to maintaining the agencies' budgets in real terms is not appropriate.

"Body of a snake and the arms of a gorilla" indeed.