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I've been staying out of this for various reasons, but I must jump in here. I smell a whiff of creationism...
You cannot extrapolate the Moon's current recession speed (4 cm/yr) back in time very far. The current rate of recession is known to be high because of a peculiar resonance with the ocean; the friction caused by the moving tidal bulge is very high right now. In the past, although the Moon was closer, the actual amount of friction it caused by tides was smaller. The efficiency with which the Earth's spin energy was transferred to the Moon was lower, and so the Moon's recession rate was slower. Extrapolating the Moon's recession rate backwards using a constant velocity is therefore an incorrect method. This has not stopped creationists from using it, however, to "prove" the Moon cannot be more than a few million years old, not billions. I am unsure how this helps their cause, of course, since that is still more than 6000 years. Nonetheless, I get a bit antsy when this argument is used. For more, check out talk.origins. <font size=-1>[ This Message was edited by: The Bad Astronomer on 2002-04-01 00:33 ]</font> |
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This is my last try, and then I'm giving up.
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1) yes. 2) no. Centrifugal force is a fictional force invented to account for the *apparent* outwardly directed force when the observer is in a rotating reference frame. 3) yes. Quote:
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I've demonstrated both mathematically and through example that it's wrong. You haven't refuted (or tried to refute) either my math or my example, so I must conclude that this conversation can't go any further. I wish you luck clearing up your confusion, but as long as you insist on holding onto false premises, I don't think you're ever going to get anywhere. Yours sincere, Don |
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I agree with Don about this not going anywhere. Gary is not responding to either Don's questions of where the "other" force is coming from in the ice-skater example, nor has he answered my questions about the evidence.
Hopefully Gary will repond to our specific questions, and not simply trot out his lumber example again.
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Jeff Schwarz __________________________________________________ Argh!! They booby-trapped their sun!!****--Invader ZIM |
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[Jeff Schwarz
Said: Hopefully Gary will repond to our specific questions, and not simply trot out his lumber example again. ------------------------------------------------------------------------ Originally it was not my intention to respond to things like this, but to you as author of this thread, I feel an obligation. 1) Ice-skater example. An Ice-skater eats their "Wheaties" (external) that supplies the electricity, to cause thought, to control, and nourish muscle. 2) Questions about the evidence. I'm somewhat confused, are you talking about the layered tidal sands and corals that were formed *long* before the Moon could have even come into orbit? I was quite sure that the first thing we needed to do was find out when the Moon arrived in orbit. 3) Don's questions. SUCH AS SEE PREVIOUS POST Quote: You haven't refuted (or tried to refute) either my math or my example, so I must conclude that this conversation can't go any further. I have tried to explain that the math, regarding a torque, applied to an inertial mass, by a gravitational force, requires a secondary force. I thought the lumber yard thing would work. [img]/phpBB/images/smiles/icon_frown.gif[/img] Try this: Walk over to the closest (hinged door) open or close the door. That is torque. It takes one force to move the door, and one to hold it to the wall or hold the wall up. Newton's universal law of gravitation has what might be called an addendum, which goes like this. "A further property of gravitation is that the gravitational force obeys the law of superposition." And. "That is, the force between any two bodies is unaffected by the presence of other bodies." xxxy xxxx o zxxx If you let the x's, the y, and the z represent Earth, and the o the Moon. You will find that gravitational force between y and o can not affect the force between y and z. Inversely the force on z by o will not affect y. If the parallelogram xyxz were to rotate it would need to be due to something other than o. ------------------------------------------------------------------------ Kaptain K Posted: 2002-03-31 22:45 ------------------------------------------------------------------------ So Gary, You are right and every PhD Astronomer, Geophysicist, and Mathematician in the world is wrong. What, exactly, are your credentials that we should believe you over them? ------------------------------------------------------------------------ Fantastic. Kaptain, I must compliment every one who thinks. Please leave the Geophysicists, and Mathematicians out of this. I have no credentials. I never went to your fancy schools. Perhaps the only things going for me are these; I read, I think, and I won't lie to you. Last night I posted a message here. This morning I found every one angry at me. It has been my experience that 90% of all anger, comes from fear. What are you guys afraid of? I don't want your jobs I have grandchildren to raise. I have asked several times that you do the math. All you do is quote the books and tell me I'm wrong or imply worse. [img]/phpBB/images/smiles/icon_frown.gif[/img] It looks to me as if only one person has tried the math. They (dapted Posted: 2002-03-29 01:50) came up with 1.5 million years which BTW is wrong and you may remember I suggested a slight correction. I know this is repeating myself, but I need to know if you heard me. The Moon is moving away from the Earth along a vector. That vector is not just the 3.8 cm per year, but must also include the recession of nodes motion of 1 revolution every 18.6 years. Is that, or is that not correct? Could someone (with credentials) please get out a chalkboard and tell us if that is correct? To solve a problem you must define it correctly. I could waste my time and try to answer all the negative comments, but an answer to the above will due for now. Gary |
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Note that y is closer to o; by the inverse square law, it is more attracted. z is farther away, and by the isl, is less attracted -- and, in fact, is so much less attracted that it does not compensate for the additional attraction felt by y. Thus, the force drawing y toward o is unbalanced, overall. Assuming that, due to orbital velocity, the overall p-gram does not actuall draw nearer the moon, it will, at least, rotate until y is closest to the moon. Do the math: Fyo^2 :: 170 Fz0^2 :: 383 Is anyone good enough to do a simple BASIC sim? (I think I am, but I'm not wholly sure...) Silas |
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Because I have done the math. |
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I'm going to take this somewhat out of order.
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But on to answering your points. Quote:
So an ice-skater gets on the ice and starts to spin. Then, she pulls in her arms and legs, and due to conservation of angular momentum, she spins faster. Sure, it takes food to get the energy to get on the ice and do all this, but once she gets spinning that's it. Pulling in her arms is negligible in terms of the energy that's already in her spin. Simple conservation of ang. momentum is all that's needed to speed up her spin. No external energy is needed. Do we agree on this? If so, then the same applies to the Earth-Moon system. If the moon is getting farther away (and we can see that it is with the lasers bouncing off the Moon) then it [bold]has[/bold] to be going slower. Simple conservation of momentum. Quote:
As for the corals, they don't speak to the issue of the Moon per se, but they do indicate the number of days in the year. If you take the number of seconds in a year to be roughly constant, then the length of the day has to have been shorter. Any theory counter to the prevailing one should explain the length of the day in the Devonian period. Quote:
If I'm taking you to task for not answering my issues, the blade cuts both ways. [/quote] I have tried to explain that the math, regarding a torque, applied to an inertial mass, by a gravitational force, requires a secondary force. I thought the lumber yard thing would work. [img]/phpBB/images/smiles/icon_frown.gif[/img] [/quote] I disagree with your analogy. When you deal with a piece of wood compared to the Earth, then you can assume point masses, since the tidal effects will be negligible. As for the Earth-Moon system, things get more complicated. When you describe the orbit, you can treat them as point masses orbiting a barycenter. That's fine. But from the near side of the Earth to the far side, the Moon pulls differently. It pulls harder on the near side of the Earth than the far side. This deforms the Earth. The bulge then gets tugged on causing a torque. You don't need an external force to cause a torque. You just need a difference in forces. Imagine a merry-go-round that is not fixed to the ground. It just pivots on a spike, like a top. I come a pull to start it spinning. I just added torque. What was the "other" force holding it? That's not a great example, but the best I can do on short notice. I'll play with the math later.
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Jeff Schwarz __________________________________________________ Argh!! They booby-trapped their sun!!****--Invader ZIM |
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So let's take one that's stationary. You pull on it to start it spinning: by the laws of conservation of angular momentum, the earth takes on a (small!) contrary spin. The energy comes from your biological energy, and ultimately turns into heat. The same is true for the friction of your feet against the ground, and your hands against the merry-go-round. The m-g-r's inertia resisted your efforts; ordinary Newtonian F=ma explains just about everything here. What's your point? Silas |
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Silas.
------------------------------------------------------------------------ I inserted dots to be empty space, otherwise the parallelogram seems to turn into a square on my display, and the moon rushes up to earth adjacency... ------------------------------------------------------------------------ Thank you. I'm old, but new at this BB computer stuff. My $5 a month on line doesn't let me proofread and set type as I should. I'll try to remember the picture hint. Perhaps I could store a .gif and leave a url. ???? Build my own chalkboard. [img]/phpBB/images/smiles/icon_smile.gif[/img] Geo3gh quote: ------------------------------------------------------------------------ Hmmm. Maybe this is something we agree on. Maybe not. So an ice-skater gets on the ice and starts to spin. Then, she pulls in her arms and legs, and due to conservation of angular momentum, she spins faster. No external energy is needed. Do we agree on this? ------------------------------------------------------------------------ Hum. The arms and legs must be pulled inward against the outward acceleration created by the rotation (centrifugal force). The energy for that was chemically stored from an external source. "Wheaties" I still think the energy has to be called external. Quote: ------------------------------------------------------------------------ If so, then the same applies to the Earth-Moon system. If the moon is getting farther away (and we can see that it is with the lasers bouncing off the Moon) then it [bold]has[/bold] to be going slower. Simple conservation of momentum. ------------------------------------------------------------------------ Yes, maybe, most definitely. This is where it gets tricky. In your above paragraph you used the word slower not slowing that makes you absolutely correct. Now for the question of slower than what, and in relation to what. Let me start with the Sun. The Sun has a mass nearly 330,000 times that of Earth. The Earth has a mass more than 81 times that of the Moon. All 3 of these bodies are going in the same general direction around the Galaxy. The Sun goes in what might be called a straight line at a more or less fixed speed. The Earth on the other hand follows a helix at almost 90 degrees to that line. Once a year when the Earth crosses an imaginary line to the stars, we find the Earth to have fallen behind by 0.68 seconds. My first question is: Was it Earth's axial rotation, helical rotation, or the linear movement around the Galaxy that caused the leap second? Next. The Moon follows a helical path about 5 degrees tilted from the plane formed by the Earth's helix. Again, once a year it is found that the Moon has fallen away from the Earth 3.8 cm. If I get this wrong please don't take my head off. In that same year, the 5 degree tilt recesses or backs its way 1/18.6 of the way around the Earth. Second question: Was the 3.8 cm measured along the helix or the Galactic linear? This is my (one man's) opinion. Because the Moon is so close to a huge mass (Earth), and because the Earth is so close to a huge mass (Sun) the helical speeds are fixed. Because the Sun is so massive it is slowly trying to move away from the Earth. Likewise the Earth is moving away from the Moon, but that motion is in a linear direction around the galaxy. As you said: Simple conservation of momentum. The Moon is not slowing. The Earth is not slowing. They are just going to slow to keep up with the Sun. PS And you thought you lost sleep! Quote: ------------------------------------------------------------------------ length of the day in the Devonian period. ------------------------------------------------------------------------ First things first. ------------------------------------------------------------------------ GrapesOfWrath Quote: ------------------------------------------------------------------------ The way I remember it, not only did I also do the math, I corrected dapted's. You can look it up. I even showed my work. ------------------------------------------------------------------------ Yes, and you were wrong. [img]/phpBB/images/smiles/icon_frown.gif[/img] You only used the 3.8 cm. The vector that the Moon follows includes the recession of nodes. See my discription above. Gary |
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What your door analogy misses is that the door would still spin "open", even if there were no force to hold it to the wall. You don't need two forces. The *net* force (vector sum of all forces acting on the object) just has to be not pointed at the center of mass. That's all you need. Quote:
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And that's all I have to say about that. Don |
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Darn it. Don beat me to the lumber on ice example. I was thinking of that on my way home.
I retract my merry-go-round example, since it doesn't do what I want. Please ignore it.
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Jeff Schwarz __________________________________________________ Argh!! They booby-trapped their sun!!****--Invader ZIM |
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Yes, she needs fuel to pull her arms in. But if I'm not already spinning, pulling my arms in does not start me to spinning. But if I'm spinning with my arms extended, I will spin at some rate R1. I pull my arms in, and I spin at an increased rate R2. If I pull my arms in linearly towards my center, how is this causing me to spin faster? I say that it is due to conservation of angular momentum. Is it your position that the energy used to retract my arms is also translated into pushing me to rotate faster? My position is that the energy used to pull my arms in only effects my arms. It does not add extra energy to my rotation. The energy in my rotation is constant. But since with my arms pulled in I have a smaller inertia, my rotational rate has to increase to keep the energy the same. I give this link as a description of angular momentum and its conservation: http://theory.uwinnipeg.ca/physics/rot/node7.html and while I'm at it, here's something on Torque: http://scienceworld.wolfram.com/physics/Torque.html (The only reason I'm putting the links here is so you and I have a common set of definitions and equations. These are what I am using. Do you wish to use other definitions and/or equations?)
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Jeff Schwarz __________________________________________________ Argh!! They booby-trapped their sun!!****--Invader ZIM |
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Just to provide a little "dressing" to this lunar "salad" thread - here is Bonestell's old 1952 LIFE magazine cover depiction of the early Moon as seen from Earth. Looks very close as seen from Earth billions of years ago, and before life. (Including LIFE magazine.) [img]/phpBB/images/smiles/icon_wink.gif[/img]
And here is his painting of the Earth - Moon system forming within the early disc of the solar system. I know this doesn't contribute much to this thread. It's just fun to look at. Bonestell is speculating in a creative way. Chip |
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<HTML><FONT BACK="#ffffff" style="BACKGROUND-COLOR: #ffffff" SIZE=3 PTSIZE=12>Excuse me while I try out the the chalkboard.
This gif drawing is to try show Moon's trajectory in red, as it vectors outward and backward around the blue Earth, the yellow grid being the plane of the elliptic. All that being within a cubical of space. Recession of nodes .gif Gary</FONT></HTML> <font size=-1>[ This Message was edited by: Gary Redmond on 2002-04-02 17:17 ]</font> |
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Jeff Schwarz __________________________________________________ Argh!! They booby-trapped their sun!!****--Invader ZIM |
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Well, Gary, I've done the math you've requested. My darn job kept getting in the way, but I finished it.
******************************** Given Distance of Moon to Earth: R<sub>me</sub> = 3.911 x 10<sup>8</sup> m [I am taking this as center-center, not surface-surface] Orbital circumference of the Moon: C<sub>me</sub> = 2*R<sub>me</sub>*pi = 2.457 x 10<sup>9</sup> m Orbital period of Moon: T = 27.32166 days Radius of Moon: R<sub>m</sub> = 1.738 x 10<sup>6</sup> m Mass of Moon: M<sub>m</sub> = 7.352 x 10<sup>22</sup> kg Radius of Earth: R<sub>e</sub> = 6.36627 x 10<sup>6</sup> m Mass of Earth: M<sub>e</sub> = 5.976 x 10<sup>24</sup> kg G = 6.6726 x 10<sup>-11 m<sup>3</sup> kg<sup>-1</sup> s<sup>-2</sup> ************************************************** ********* 1) Linear speed of the Moon: v = C<sub>me</sub>/T = 8.993 x 10<sup>7</sup> m/day 2) Moving away from Earth against gravity, how fast "V" was it going when it hit? Hint: V=v*e<sup>2</sup> [I have to admit I don't follow you here. But, assuming that by "e" you mean the base of natural logarithms, and "V" is the initial speed and "v" is the v we get in 1)...] V = 6.645 x 10<sup>8</sup> m/day 3) If the Earth and Moon touched their center to center distance D would be what? D = R<sub>m</sub> + R<sub>e</sub> = 8.104 x 10<sup>6</sup> m 4) [I don't know what you're looking for. The acceleration due to gravity on the Earth, or on the Moon? Or are you looking for the force of gravity between the Earth and the Moon if they were touching?] 5) using 9.8 m/s<sup>2</sup> = g V = 6.645 x 10<sup>8</sup> m/day = 7,690 m/s A = V<sup>2</sup>/2g = 3.016 x 10<sup>6</sup> m _________________ Jeff Schwarz __________________________________________________ Oh freddled gruntbuggly thy micturations are to me As plurdled gabbleblotchits on a lurgid bee. <font size=-1>[ This Message was edited by: Geo3gh on 2002-04-02 20:37 ]</font> <font size=-1>[ This Message was edited by: Geo3gh on 2002-05-03 12:18 ]</font> |
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Geo3gh
Quote: ------------------------------------------------------------------------ Clear enough so far. I notice that you don't connect the endpoints of the Moon's orbit. On purpose? ------------------------------------------------------------------------ Yep, that is the recession of nodes, and lunar regression. The Moon *appears* to loose 1/18.6 revolution and moves outward the 3.8 cm every year. If the endpoints connected we wouldn't be having this discussion. Quote: ------------------------------------------------------------------------ Well, Gary, I've done the math you've requested. My darn job kept getting in the way, but I finished it. ------------------------------------------------------------------------ Very good. Thanks. Now let me try to show how and why, I did what I did. The easiest way is to send you to my web page. The first page Hypothesis I tries to explain why I think the Moon touched the Earth. This second page does the math to show when it happened. Hypothesis II</FONT> Gary |
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I haven't had a chance yet to look over the entire page, but there's a quite a bit to read there.
One (off topic) suggestion I have is in your html. You can show exponents with the "<sup>" tag. I'll have more for you after I work my way through your pages. Quote:
Jeff Schwarz __________________________________________________ Oh freddled gruntbuggly thy micturations are to me As plurdled gabbleblotchits on a lurgid bee. <font size=-1>[ This Message was edited by: Geo3gh on 2002-04-02 20:38 ]</font> |
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OK, I've read enough of Gary's page.
I don't even know where to start. But it's basically a full set of pages detailing Gary's theory. Most of his theory has been in this thread, but I got a much clearer view of it reading his page. But I see many major problems with it. Gary, I don't know that this is the place to start a point by point discussion of your page (probably not), but I'd be happy to discuss it with you offline. I'll send you my e-mail address if you'd like. Even if we don't agree on theory, I can help clean up your html. [img]/phpBB/images/smiles/icon_smile.gif[/img]
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Jeff Schwarz __________________________________________________ Argh!! They booby-trapped their sun!!****--Invader ZIM |
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I just realized this afternoon that I made a mistake, so in the interest of intellectual honesty, I'm owning up to it. Unfortunately for Gary's theory, it's just a mistake in my choice of examples, not in the underlying math. I should not have used the ice skater analogy. When the ice skater moves his/her arms, the moment of inertia changes, and the angular velocity changes to compensate. Net angular momentum does not change, as there is no torque in the system.
So, my bad. Kicking the lumber on the ice is, however, still a perfectly valid illustration of how an object can have a non-zero torque applied to it by a single force. Of course, the net torque on both the kicker *and* the lumber together has to be zero, so either there has to be enough friction with the ice to absorb it, or the kicker will fall flat on his... Well, there it is... the analogy holds, though. Depending on how you look at it, the earth is the kicker, and the moon is the lumber. The moon is spinning away, and the earth is falling on its butt (i.e. slowing its rotational speed.) Sorry about any confusion caused by the spinning ice skater mistake. Yours, Don |
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It appears to be slowing by one revolution every 18.6 years? I've been alive for more than twice that, and I haven't seen that slowing. One revolution per 18.6 years? What do you mean by a revolution then? Also from that page, given number 9: "During that one second the earth moves 29 970 meters around the sun, but the prime meridian at the equator moves in the opposite direction 463 meters." What do you mean by "opposite direction"? The Earth rotates in the same direction as it orbits the Sun (counterclockwise, as seen from above the North pole). When a leap second is added, it is added at midnight, UTC time, which means it is midnight on the prime meridian--the prime meridian is away from the Sun. At that time, a point on the equator is going approx. 463 meters per second (that's about a thousand miles per hour), but it would be in the same direction as the Earth is moving in space (except for the 23 1/2 degree tilt). So, I'm not sure what is meant by that. |
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Geo3gh
Posted: 2002-04-02 21:13 ------------------------------------------------------------------------ OK, I've read enough of Gary's page. Even if we don't agree on theory, I can help clean up your html ------------------------------------------------------------------------ I must thank you once again for at least taking the time to look at it. You say "html" that is being way to kind. When I started that page 8 years ago every thing was "htm" not "html". Unfortunately I have financially stagnated way back there. So even If my page was "html" I probably couldn't read it. AOL provides 2 meg of page space. My page is at 1.11 meg and as compact as I can make it. You also suggested using the "<sup>" tag I really tried that about 6 years ago but never could get it to work for me here on this fossil. I think the "<sup>" tag needs a "</sup>" tag which would add over 11 byte at each use I'm not sure I can handle it. "Agh" that's enough of my woes. OK, here's the deal as bad as my page may be it is written from the heart. As I said before, I will not lie to you. Everything in that page is as honest and factual as I could make it. All the numbers, math, and physics, are as straight out of the book as I could make them. And, yes it was a shock to me when I first came up with the conclusion that the astronomy books were wrong. Let me say this one more time then I'll try to shut up. 1) The Earth and Moon fall around each other's center of gravity. 2) Their masses are not suspended from another source (other than the sun). 3) So therefore they can not I repeat "can not" torque each other. 4) Yes, the Earth and Moon are moving away from each other. 5) That motion is purely one of momentum. Example: (Please don't laugh or call on "Velikovsky") If two pool balls collide they come together and move away from each other following Newton's laws. Gary PS I would like to try answer some of the questions proposed by GrapesOfWrath, but need to rush out of here. Later. |
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Hey, GoW, did you notice your new designation?
[img]/phpBB/images/smiles/icon_wink.gif[/img] I think BA does this on purpose. I hope that doesn't discourage you and stop you from posting. I have been enjoying this BB, however not qualified enough to add my two cents' worth [img]/phpBB/images/smiles/icon_frown.gif[/img] I wonder what designation comes next [img]/phpBB/images/smiles/icon_lol.gif[/img] |
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Is that not the case? I was using Unix when the web came on line (anyone else remember Lynx and Mosaic? Tee hee. Remember when Mosaic would post on their home page all the new sites that had come on line that day?), and I figured since it was originally designed by academics at CERN, they would have been using Unix. I only started noticing the ".htm" ending when Microsoft got into the action and started hosting web servers. This is my last shot at it, too. Quote:
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I tried to look at your web page, but I couldn't seem to get through. It just sat there stalled for a long time until I gave up. Best of luck, Don |
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Gary, you wrote your page in HTML just like everyone else. Jeff Schwarz <font size=-1>[ This Message was edited by: Geo3gh on 2002-04-03 14:33 ]</font> |
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