May 09, 2005

The harpoon mechanism

You can run off on the craziest tangents while writing lectures. Tomorrow's lecture will discuss the rates of chemical reactions. There is a special kind of reaction that is unusually fast-- one of the reagents throws an electron at the other and in the process they both become ions. The two ions are then attracted to each other by Coulombic force giving the reaction an unusually large cross section. This kind of reaction is said to take place by the harpoon mechanism, and so I went surfing to find a cool old picture of a whale hunt. Here's part of an old tale of the sea that I found:

The Whale Ship Essex On the 20th of November 1820, the Nantucket whaling ship ship Essex (87 feet long with a 21 man crew) found a group of sperm whales in the South Pacific, the whaling boats were launched and the hunt began. A man named Owen Chase the first mate harpooned a large bull which trashed about with its hugely powerful flukes and smashed a hole in the boat. The men on the boat managed to stuff some cloth into the hole, reluctantly cut the whale loose and made it back to the Essex safely.

This in itself was not an unusual occurrence, whale boats not uncommonly sustained damage from whales and a certain amount was expected. What Owen Chase and the other whalers saw next however was most definitely unusual. The stricken whale had come close to the ship and was swimming headlong towards it, Chase recalled "He came down on us with full speed, and struck the ship with his head ... and he gave us such an appalling and tremendous jar as nearly threw us all on our faces."

The whale had made a hole in the stout timbers of the ship and the crew began to pump out the water and attend to the hole. A few minutes later however and one of the crew shouted out "Here he is - he is making for us again!".

Chase said "I turned around, and saw him ... coming down apparently with twice his ordinary speed, and to me at that moment, it appeared with ten-fold fury and vengeance ... The surf flew in all directions about him, and his course towards us was marked by a white foam ... which he made with the continual thrashing of his tail; his head was about half out of the water, and in that way ... he came upon, and again struck the ship."

0 Comments:

Post a Comment

Subscribe to Post Comments [Atom]

<< Home



Web Counter
Web Site Counter

Powered by Blogger

Subscribe to
Posts [Atom]