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By herbert (Sun Sep 07, 2008 at 10:55:18 AM EST) science, questions, maps, books (all tags)
  • Science question
  • Literary cartography
  • Short book reviews

Science Question

Tidal energy is counted as renewable but clearly the energy has to come from somewhere.  What happens if you put stuff in the way of tides?

  1. It makes the moon slow down and eventually crash into the earth.
  2. It makes the earth's rotation slow down and eventually stop.
  3. It cools down the sea by reducing the friction of the water sloshing about.

Literary cartography

Recently read "The Riddle of the Sands" by Erskine Childers, which includes regularly referenced maps and nautical charts of the German North Sea coast.  This has made me think about books with maps in them.

The first mappish books I thought of were Ursula le Guin's Earthsea - by the end of the original trilogy the dude had been pretty much everywhere on the map.

I seem to remember that The Hobbit and Lord of the Rings have unconvincing maps with rectangular mountain ranges.  However, Lord of the Rings gets bonus points for having a fold-out map, in the edition I read.

I suppose a lot of other fantasy books have maps in them, but I don't read many of them.

All the best detective stories include plans of the house, of course.

From my childhood reading I think that most of the Swallows and Amazons books have maps in them.

The Courts of the Morning by John Buchan is one I reread a while back - this also suffers from the rectangular mountain range problem.  It's about a small war in South America.  You'd expect military books to go in for mapping but I don't read too many of those either.  The Flashman books have maps I suppose.

I have as yet formed no significant conclusions on the important topic of literary cartography, except that all books should have maps if at all possible.  Maybe I'll go and draw some for Pride and Prejudice.  I expect Jane Austen would have done that if she'd thought of it.

Short book reviews

Beyond Black - Hilary Mantel.  Black comedy about a medium.  Good.

The Butt - Will Self.  Set in fictional country vaguely like a third-world Australia with violent tribes etc.  Dull, disappointing.

Atonement - Ian McEwan.  Good.

The Janissary Tree - Jason Goodwin.  Crap.  Did the hero continually think things to himself in single line paragraphs with gratuitous italicization?

Yes he did.

I think I remember the Da Vinci Code using the same irritating device but maybe it was something else.


Apparently this is my first diary since 2004.  I think I posted a couple of Holes in the meantime though.  Nothing really happened anyway.  I don't know if I'll become a real diarist.  I am posting this at the weekend so as to retain my amateur status.

< Work it, baby | You gotta do what you gotta do. >
Diary | 12 comments (12 topical, 0 hidden) | Trackback
Hey, I know science by Greener (4.00 / 1) #1 Sun Sep 07, 2008 at 11:17:55 AM EST
Not really but I can make stuff up that makes sense. This answers questions 2 and possibly one.
As for number 3 I would image the effect is negligible compared to other heat sources.

While the moon and tidal bulge affect each other the source of the energy itself is from gravity which doesn't get used up like a windmill removes energy from wind. A rock falling to earth is being accelerated by gravity but doesn't remove that amount of energy from the earth's total gravitational pull. From what I understand the source of gravity's energy or force (for lack of better terms) comes from subatomic particles/fields which the LHC is supposed to help us try and identify and understand.

This is all off the top of my head so hopefully a real scientist type can step in and tell me if and where I'm wrong and explain it better than I did.

I suppose a question to ask is by Greener (4.00 / 1) #2 Sun Sep 07, 2008 at 11:25:30 AM EST
if we can develop a device that can harness the force exerted by gravity without it being first transferred through an intermediary object (like water flowing through a dam for example) as kinetic energy would this device be a free energy machine and how much energy would we be able to extract from earth's gravitational field.

[ Parent ]
The energy... by ana (4.00 / 1) #3 Sun Sep 07, 2008 at 11:39:21 AM EST
comes out of the orbital kinetic energy of the moon, and the rotational kinetic energy of the earth, which decrease as a result. Most of the energy is wasted, of course (it always is), and that waste heat goes into the environment. Much of it, in this case, is dissipated in turbulent motion of the water around your obstructions, which goes into heating the oceans, ever so slightly.

"And this ... is a piece of Synergy." --Kellnerin

[ Parent ]
Also by Herring (4.00 / 1) #4 Sun Sep 07, 2008 at 02:35:07 PM EST
wind turbines are effectively sapping energy from the rotational internia of the earth (coriolis forces, trade winds etc.) but you'd have to put up a lot of them to make a difference. Technically wind, wave and tidal power are non-renewable, but over a very long time.

I suppose that all energy is non-renewable over a long enough timescale.

christ, we're all old now - StackyMcRacky

[ Parent ]
Seems to me by herbert (2.00 / 0) #8 Mon Sep 08, 2008 at 12:11:38 AM EST
the main thing is to make sure the Earth is pointing in a good direction when it stops spinning.  If we point the populated parts at the sun, we can save a lot on lighting, so we'll be OK even if there is less wind.

[ Parent ]
Actually by ks1178 (4.00 / 1) #11 Mon Sep 08, 2008 at 08:18:46 AM EST
If the earth stopped spinning, the wind would still be there, and possibly become stronger than it currently is.

Warm air on the side facing the sun, would then get out of balance with the colder air on the dark side.

[ Parent ]
Sounds like an exam problem by garlic (4.00 / 1) #12 Tue Sep 09, 2008 at 02:38:20 PM EST
If you concieve a tidal energy harvesting system so effective that it prevents the actual ocean tide from happening, what would be the change in the orbit of the moon, and the revolution of the earth?

[ Parent ]
Science Answer: by ammoniacal (4.00 / 1) #5 Sun Sep 07, 2008 at 05:36:12 PM EST
I am praying for ALL THREE.

Also, this is the only map anyone really requires for Pride & Prejudice.

"To this day that was the most bullshit caesar salad I have every experienced..." - triggerfinger

It's amazing to think someone made that thing by Clipper Ship (4.00 / 2) #6 Sun Sep 07, 2008 at 06:03:34 PM EST
What is the cat-level required to force into making something like that? 3 cats? 4? Possibly a level-7 cat infestation?

I say 6. And an unholy love of cardigans.


Destroy All Planets

[ Parent ]
unholy love of cardigans by ammoniacal (4.00 / 1) #7 Sun Sep 07, 2008 at 07:58:28 PM EST
That's fairly redundant, innit?

"To this day that was the most bullshit caesar salad I have every experienced..." - triggerfinger

[ Parent ]
Splendid by herbert (4.00 / 1) #9 Mon Sep 08, 2008 at 12:15:37 AM EST
Although there doesn't seem to be any indication of which way north is, or where the body was found.

Also it looks like a travelling salesman would have a hell of a time visiting all these people.  (humorous nerd joke, pls ignore)

[ Parent ]
In the hall by sasquatchan (4.00 / 2) #10 Mon Sep 08, 2008 at 04:05:32 AM EST
with the candlestick by Mr. Green.

[ Parent ]
Diary | 12 comments (12 topical, 0 hidden) | Trackback