[ClearCase_guy]

Anyone who has seen what the Greeks and Romans had for “mirrors” would know that reflecting and focusing the sun’s rays into a long distance incendiary device was a ludicrous notion.

[Alex Murphy]

For the last time: Archimedes did not invent a death ray.

No, but the Atlanteans did.

[bert]

Difinitive Reference: Muthbusters Episode 46: Archimedes’ Death Ray

The theory was busted not once but twice by the engineers at Mythbusters.

Here's the video.

[norwaypinesavage]

"But in practice, the tiny difference in volume between a crown made of pure gold and one made of a mixture of gold and silver is too small to be reliably measured."

Leave it to the NYT to get even this wrong. The density of silver is 10.5 grams per cc while the density of gold is 19.3 grams per cc. There is nearly a 2 to one difference. It would be quite easy to determine the difference using Archimedes Principle. Simply weigh the amount of water displaced by immersing the crown in water to determine its volume. Then weigh the crown and divide by the volume. If it is anything less than 19.3 grams per cc, off with his head.