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BobTheScientist
1645.  Wed Nov 19, 2003 4:53 am Reply with quote

No but the following springs to "mind":

“An angel whose muscles developed no more power weight for weight than those of an eagle or a pigeon would require a breast projecting for about four feet to house the muscles engaged in working its wings, while to economise in weight, its legs would have to be reduced to mere stilts.” JBS Haldane

I thought it must be in Haldane’s famous essay On Being the Right Size, which someone has put in full on the wuh:
http://irl.cs.ucla.edu/papers/right-size.html

It isn’t, but another graphic Haldane quote is:
“You can drop a mouse down a thousand-yard mine shaft; and, on arriving at the bottom, it gets a slight shock and walks away, provided that the ground is fairly soft. A rat is killed, a man is broken, a horse splashes.”

 
Jenny
1648.  Wed Nov 19, 2003 7:46 am Reply with quote

Regarding bumblebee aerodynamics, here's the skinny from a man who sounds as if he ought to know:

Quote:
I have heard this story so many times, but I suspect it is urban legend.

Well, I don't know if I can debunk the urban legend, because I have heard several versions regarding its origin. I can, though, explain why it is easy to come to the improper conclusions with regard to bumblebee aerodynamics.
The apocyphal story I have with regard to the legend is that an aerodynamicist worked up the aerodynamics of the bumblebee on a lark, and found, based on his assumptions (i.e. flat plate aerodynamics over the wing, a certain beat frequency and airspeed [indicating an oscillatory angle of attack on the wings], imposition of the Kutta condition, etc), that the power requirements were far beyond the capacity of bumblebee flight muscles to provide. Moreover, the wings were stalled through a large percent of their flap cycle, yielding horrendous L/D penalties. He confided his result to another during a reception to which the press had been invited; it was overheard by a member of the press, and the rest was media history. The aerodynamicist was reported to have realized an error in his [tacit] assumptions later during the event, but the damage had been done.

As I said, an apocryphal tale.

The key to understanding bumblebee (and dragonfly and butterfly and mosquito) aerodynamics is in understanding bumblebee airfoils. If you imagine a bee's wing, with its veins and undulations in cross section, the first question that comes to mind is, "why would anyone pick such a horrible airfoil and try to fly with it?" Of course, individual bumblebees have little choice in the matter, but mother nature *could* have chosen another design. Bees have been part of the biosphere since the late Cretaceous (they coevolved with the flowering plants). If another insect were to develop, which could fly and pollenate flowers with greater ease than the bee, it would have had a survival advantage and taken over (it should be noted that bees have several other survival advantages as well).

So why isn't there a bee-sized insect out there with a NACA 64-series airfoil?

The answer is scaling. At the sizes of bee wings, the bumpy-looking wing cross section is actually a very efficient airfoil. The key is to recognize that at bee dimensions, Reynolds numbers are low! Many of the fluid dynamic assumptions students use in the study of airfoils do not hold up (since few airliners are built to bee dimensions, the assumptions are still fine for most of us aerocritters). Once you have a higher Cl airfoil, the L/D goes up and power requirements go down.

And, voila! the bee flies!

This is what our hapless hero realized, too late to hold the presses (if you believe this version of the story).

Actually, at small scale, and low Reynolds numbers, a surprising variety of structures become quite good flying machines. Perhaps one of the oddest is gossamer. Certain species of spiders have taken to the air by spinning web and holding it aloft. Once picked up by the breeze, these spiders can travel great distances and achieve fairly respectable altitudes. Often, these spiders travel en masse, and meld their webs into a flying spider colony (a few cases of UFO sightings in the 50's were attributed to gossamer).

Airborne bacteria have developed even stranger schemes...

Brent Wellman
U.S. Army Aeroflightdynamics Directorate, Ames Research Center


Source http://www.ilr.tu-berlin.de/WKA/technik/bumblebee.html

 
Flash
1656.  Wed Nov 19, 2003 4:14 pm Reply with quote

So we know the answer. Now, what's the question?

 
Jenny
1657.  Wed Nov 19, 2003 4:28 pm Reply with quote

If you were a bumblebee, would you pack a parachute?

 
JumpingJack
1942.  Sun Nov 23, 2003 5:45 am Reply with quote

Good question, Jen! That's the style...

 
JumpingJack
1943.  Sun Nov 23, 2003 5:51 am Reply with quote

Q.Which eye did Nelson wear his eye-patch on?

 
JumpingJack
1944.  Sun Nov 23, 2003 5:54 am Reply with quote

A.Neither. Nelson never wore an eye-patch.

(Though he added a sunshade to the front of his Admiral's hat like a peak).

http://www.ely.org.uk/cromwell/pNelson.htm

(s: Official BBC page, excerpting Lucy Moore's 'Great Britons')

 
JumpingJack
1945.  Sun Nov 23, 2003 6:08 am Reply with quote

Incidentally, I read somewhere years ago that when Nelson lost both his arm and his eye he was on dry land.

The link below states that Nelson's right arm was indeed shot and made useless while he was getting out of a boat leading a shore-attack at the Battle of Santa Cruz, Tenerife at abou 2.00 am on the night of 25th July, 1797.

However, he staggered back into the boat and was taken to the Theseus off-shore where it was immediately amputated by the ship's surgeon.

http://www.aboutnelson.co.uk/santacruz.htm

 
JumpingJack
1946.  Sun Nov 23, 2003 6:11 am Reply with quote

Here's an interesting side-light on that;

Quote:
A sword once carried by Nelson is to be auctioned by Sotheby's and is expected to fetch between £6,000 and £8,000.

Nelson lost his right arm in the failed attack on Santa Cruz, Tenerife, while carrying the sword.

Nelson's ancestor Captain Galfridus Walpole was wearing the sword when he lost HIS right arm fighting the French 86 years earlier.



http://www.ybw.com/auto/newsdesk/20031004122725ymnews.html

s:Yachting Monthly, 4 November 2003

 
JumpingJack
1947.  Sun Nov 23, 2003 6:44 am Reply with quote

The tourniquet* used in the boat to stem the flow of blood from Nelson's wound (the neck stock worn by his step-son Josiah Nisbet) is on display in the National Maritime Museum, Greenwich.

Other features of the exhibition include a reconstruction of the Battle of Trafalgar, created by Jim Henson's Creature Workshop (of Muppet fame), and the remains of Nelson's stump-muff 'made by Sicilian ladies from the beards of oysters'.

http://greenwichengland.com/tourism/nelson-exhibition.htm


*On loan from the Wellcome Instiitute


Last edited by JumpingJack on Sun Nov 23, 2003 4:39 pm; edited 1 time in total

 
JumpingJack
1948.  Sun Nov 23, 2003 6:49 am Reply with quote

This is cute.

Quote:
Gone
by Billy Collins
 
Gone is Lord Nelson's arm
and gone is the head of Sir Walter Raleigh
which his wife used to carry around in a satchel.

Gone is my hair
and the whole of Amelia Earhart
in the wash of her silver propeller.

And now you are gone,
gone out the door with a suitcase
and over the hill in your car.

You and Homer's eyesight.
You and the children of Hamlin.
Gone like a coin through a grate

or Byron's journals.
Real gone like bebop.
The gone that leaves a zero in the here.

All gone, as we say to children,
All gone,
holding up our empty hands.
 


Copyright © 1997 by Free Lunch Arts Alliance

 
BobTheScientist
1950.  Sun Nov 23, 2003 7:07 am Reply with quote

JumpingJack wrote:
A.Neither. Nelson never wore an eye-patch.


These A = neither answers reminds me of a quip by zennist Alan Watts.

Q. Is a zebra a white horse with black stripes or a black horse with white stripes?
A. Neither. It is an invisible horse colored black and white so nobody bumps into it.

 
DELETED
1953.  Sun Nov 23, 2003 9:43 am Reply with quote

DELETED

 
JumpingJack
1973.  Sun Nov 23, 2003 4:44 pm Reply with quote

Thanks for sorting that Garrick. You'll see some lengthy glosses on your original piece of brilliance from me and Jenny should you return to the Bible thread.

What we really need now is a top-notch classicist to confirm the theory.

 
JumpingJack
1974.  Sun Nov 23, 2003 5:26 pm Reply with quote

Bob

I think I can outquip Alan Watts on zebras with this...

A zebra dies and finds himself in Heaven. He is mooching around disconsolately when he bumps into St.Peter. "Hello", says the saint, "What's the matter with you?"

"Oh, nothing", says the miserable equid.

"C'mon", says St Peter, "I can see something's up. You can tell me, surely?"

"Well, all right...", sighs the zebra, "It's just that when I was alive, I could never work out whether I was BLACK with WHITE stripes, or WHITE with BLACK stripes, and it really used to get me down. I always assumed that, having passed beyond the Vale, as it were, All Would Be Revealed In The Fullness Of Time, but I find I'm none the wiser".

St. Peter looks him over for a few moments from various angles, and then says:

"Hmm. Yes. That IS a knotty one. Rather beyond ME I'm afraid. But, look here, there's no need to get depressed about it. It's easily resolved. All you have to do is pop over and see God –he's omniscient, as you know, and he'll be able to give you the right answer in a jiffy".

The odd-toed ungulate brightens visibly. "Really?" says he.

"Absolutely", says St. Peter. "He's just over there look". He points to heaven's distant horizon, from beyond which comes a numinous luminescence and the faint arpeggios of cerulean music.

"Great. Thanks! " says the zebra, and trots happily away into the distance.

The next day, St.Peter again encounters our friend, who is now looking positively suicidal.

"Hello," says Peter. "What's up? Didn't you see God?"

"Oh yes", says the zebra. "I saw him all right".

"Then what on earth happened? Didn't you ask him?"

"Ohhhh" moans the gloomy beast, "Yes I asked him, 'Am I white with black stripes or black with white stripes?'...But all He said was 'YOU ARE WHAT YOU ARE!! ' ?"

"But that's it!! That's the ANSWER!" says St Peter, shouting with excitement. "That's the answer! Don't you SEE?!?

"What's the answer?" asks the confused animal.

"Well, you're WHITE with BLACK stripes of course!!! It's OBVIOUS!!!" says the Saint, dancing with joy, understanding and gratitude.

"Wot?"says the zebra. "How d'you work that one out?"

"Because if you were BLACK with WHITE stripes, God would've said: 'YO IS WHAT YO IS!"

 

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