Archimedes was right

Press, Volume CXIV, Issue 33425, 5 January 1974, Page 9

Archimedes was right

(By

ROBERT C. COWEN

in the “Christian Science Monitor.")

Archimedes was fortunate not to know modern optics. Otherwise he might have talked himself out of one of his most spectacular legendaryachievements — burning a Roman fleet ' with focused sunshine.

In a recent issue of “Applied Optics,” A. C. Claus of Loyola University told how a crowd on shore might have focused the sun on the ships by sighting through peep holes in hand-held mirrors. But O. N. Stavroudis, of the University of Arizona, in the same issue, calculated that even hundreds of well-aimed mirrors would barely raise a wooden ship’s temperature by a few degrees Celsius per minute.

He adds that producing glass for hundreds of mirrors, let alone lenses, was probably quite beyond bronze age technology: “We are bound therefore to dismiss this tale as mere legend,” he concludes w«a lit* m

print than modern Greek sailors, unburdened by theory turned bronze-coated mirrors on a wooden boat and promptly set it afire. This was the latest in a series of experiments designed by a Greek engineer, Joannis Sakkas. His mirrors are flat shields, 5 feet long by 2 feet wide. Held by dozens of sailors and properly aimed, they form, in effect, a section of a large, concave, focusing mirror. In one experiment, 70 sailors aimed the mirrors. The target reportedly began to smoke within seconds and was blazing within a couple of minutes. Proves technique This, of course, does not prove that Archimedes actually did burn a Roman fleet in 'this way. There is no eyewitness report. But it does prove the legendary technique works, using what amount to bronze shields. Dr Sakkas says he believes Archimedes “definitely did have the means at his disposal to burn the Roman fleet. Jius ■is a xeminrier not

to discount the technological prowess of the ancients. Archimedes himself knew the principle of the lever and the pulley. He reportedly used them to good effect in war engines directed against Romans at Syracuse.

Elsewhere, remains have been found of what looks like a first century B. C. navigational computer. It has a complex gear train whose engineering suggests a more advanced technology than we have attributed to the Greeks. There are even hints of a little electrical know-how. Pots 2000 years old from the site of old Bagdad seem to have been batteries. They contain upright sheet copper cylinders with iron rods inside, rods corroded as though attacked by an acid. Rod and cylinder are insulated from each other by pitch. Such batteries might have been used to electroplate metals for jewellery. Tales of gods and magic may well invite scepticism. But when they fall within the range of the physically possible, we should not discount legends of ancient technology out of hand