http://www.theflatearthsociety.org/tiki/tiki-index.php?page=Experimental+Evidence
I'll go over why these don't work:
It is proven that the ship does not sink behind a hill of water, but that it is actually perspective which hides it. This demonstrates that the earth is not a globe. There have been experiments where a half-sunken ship has been restored by simply looking at it through a telescope, showing that it is not actually hiding behind a "hill of water": http://www.theflatearthsociety.org/tiki/tiki-index.php?page=Ships+appear+to+sink+as+they+recede+past+the+horizon
Do you not comprehend perspective? Things can't hide behind vanishing points, or ever reach them - you can think of it like zeno's paradox. Looking at the sail would make the ship bottom appear smaller (by a hair), however moving your view downwards would reverse the effect.
http://www.sacred-texts.com/earth/cc/cc21.htm
Didn't bother to read through all of this, but I'm really not convinced. There are hundreds of stories of sailors seeing ships go under the curvature, however you of course only listen to the few articles with opposing views.
Tom Bishop conclusively demonstrates that the earth is flat here: http://www.theflatearthsociety.org/forum/index.php?topic=18114.msg319626#msg319626
First off, I want to say that your math is wrong. I ended up with around 190-200 feet that should be obscured. I really doubt you could see anything 34 curved miles away. Have any pictures to show?
Professor Mark Fonstad of Southwest Texas University mathematically demonstrates the earth's flatness here: http://www.improb.com/airchives/paperair/volume9/v9i3/kansas.html
What does this have to do with a flat earth? Topology is not measured in height from the bottom of the earth! It's measured from sea-level, and thus equaling a flat surface.
There are further experiments which demonstrate a Flat Earth in the book Zetetic Cosmogony by Thomas Winship: http://books.google.com/books?id=GzkKAAAAIAAJ&pg=PA#PPP9,M1
I'm not going to read through this monster! If you point out some key points I'll look into them however.
Daniel Shenton has demonstrated it here on the Old Bedford Canal: http://www.theflatearthsociety.org/forum/index.php?topic=34316.msg841118#msg841118
What? He said he did not see a drop, that's not proof! Perhaps I'm missing something here, is that whole argument just that 1 paragraph?
Anyways, all that other stuff following seems to be from 1900 or something. I'm surprised you listen to people then, but not the ancients - who even then knew the world was round.