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        riddles >> what happened >> Cross the river
        
(Message started by: Speaker on Mar 15^th, 2004, 6:46pm)

Title: Cross the river
Post by Speaker on Mar 15^th, 2004, 6:46pm

There is a wide river with a fast current flowing from the north to the south. You are on the east side. A chest of gold is on the west side. You need to get the chest of gold and bring it back to the east side before the bandits find it. The bandits are on the west side of the river and you can hear them in the distance approaching. Once the bandits reach the river they will be able to see the chest of gold.

On the east side of the river there is a small rowboat. In the boat are a life jacket, a long rope, a big hammer, some nails, a bottle of brandy and a book. But, there are no oars, and no motor.

You are wearing a strong belt and a dagger. Your boots are made of soft leather and your hat is of straw. You are carrying a bag with your lunch and other camp gear, but it is early in the morning and you are not hungry.

There are a few tall trees growing on the banks of the river, but their lowest branches are above your reach. There are bushes, but their branches are thin and thorny. There are some rocks along the riverbank. You pick up a rock and try to throw it across the river, but it falls short. The river is too wide. You try to wade across the river, but the river is too deep. You try to swim across the river, but the current is too swift.

However, you get the gold and escape the bandits. 8)
What happened?

Title: Re: Cross the river
Post by DeMark on Mar 16^th, 2004, 10:53am

Who cares? 8)

Title: Re: Cross the river
Post by Cathos on Mar 16^th, 2004, 2:56pm

What if you tore apart the boat, and reassembled it to form a bridge, using the rope, nails, and belt as needed to secure it. Would that be fast enough of even work at all?

How about this: you tie one end of the rope around your belt, tie the other somewhere secure on the east bank (the boat, maybe, or you could make some sort of stake with the wood, hammer and nails). Then put the life jacket on. I'm assuming the rope is long enough to reach the west side. When you jump in, the life jacket will keep you from drowning, and the rope will keep you from getting swept too far downstream. In theory, you could get to the other side, if the rope was long enough and you were strong enough. To get back, tie your end of the rope to the chest, then follow the rope back to the east, and drag the chest back through the river.

Or you could just look in the book - an atlas of the surrounding area - and take the bridge that it mentions 50 yards the north.
:)

Title: Re: Cross the river
Post by Speaker on Mar 16^th, 2004, 4:21pm

There is not enough wood in the boat to make a bridge across the river. Also, this might take too much time. Depending on how fast you can build, and how fast the bandits are coming.

The rope is long enough to reach the west side.

I never considered dragging the chest back through the river, but I don't think it is possible to do that before the bandits arrive. You need to move faster.

The book is an atlas, if you want it to be, but there are no bridges. Afterall, if there was a bridge, then the bandits would chase you

Title: Re: Cross the river
Post by Icarus on Mar 16^th, 2004, 4:33pm

I assume it is a very long rope? much longer than the river is wide? If so, then there is an old trick that I am sure is the intended answer. But, living as I do in the heart of the old West, I say that you use the rope to make a big lasso, lasso the chest, and haul it back! ;D

Title: Re: Cross the river
Post by Speaker on Mar 16^th, 2004, 4:54pm

The old trick is the intended answer, padnah ;)

I wun't a thunk you could toss a lariat further than you could throw a rock. But, maybe yer a better roper than a pitcher.

Title: Re: Cross the river
Post by Icarus on Mar 16^th, 2004, 5:14pm

Now 'round these parts, them's fightin' words. But then again, round here, a "wide" river is about 20 feet, lessin' yer ah referin' to the Platte. Then ya jist walk across. What's the matter? Afraid ta get the bottoms of your boots wet? The tops'll still be high an' dry!

Title: Re: Cross the river
Post by Speaker on Mar 16^th, 2004, 5:24pm

Did I ferget to mention, that thar river is plum full of them thar peeraniyah fish. You dab one toe of jist one of yer boots and them fishes will bite it right off and suck all yer juices right out the hole in yer toe. Best stay dry if ye plan on spendin any o' that gold.

Title: Re: Cross the river
Post by Cathos on Mar 16^th, 2004, 6:00pm

Hmm... There's pirannahs in the lake, so you can't even touch the water, right? But earlier, you tried to wade and swim across, so you're already fishfood. Guess that makes gold a moot point. :P

When you drag the chest across, though, all you have to do is drag it into the water before the bandits arrive. The gold will make it sink, so they won't see it. When they ask you what you're doing, you tell them your fishing for whales with a huge rope. They'll laugh at you, and when they leave, haul in the treasure and have the last lauh gyourself.

I've no idea what the 'old trick' is.

Title: Re: Cross the river
Post by Speaker on Mar 16^th, 2004, 6:43pm

Well, the piranha did not arrive until Icarus came along wearing his cowboy boots. And, anyway, maybe the piranha are in the Platte River. But, you can get the gold without getting wet, piranha or not.

I guess you could pull the gold into the river with the rope, but I do not think that you could pull it all the way across. I cannot say it is impossible (I think it is, because there would be a lot of rocks, or soft sand or something). But it is not the answer I am looking for, the one Icarus calls the "old trick." We just have to assume that the old trick I am thinking of and the one Icarus is thinking of are the same. I think they are because of what he says.

Title: Re: Cross the river
Post by SWF on Mar 16^th, 2004, 6:50pm

Is the "big hammer" big enough that it could anchor the boat yet small enough to be thrown a reasonable distance? If so, just keep throwing it with the rope tied to the hammer, and pull the boat to the hammer, reel in, and throw again and again until across. To get back more quickly you could have tied the rope to a tree on the starting side, so the boat can "swing" back across as the current pulls the boat downstream.

If the big hammer is too large to throw, is it large enough that the handle can be layed across the river as a bridge? :)

Title: Re: Cross the river
Post by Speaker on Mar 16^th, 2004, 6:54pm

The hammer is big, but not big enough to anchor the boat in the fast current of the river. Its handle is not long enough to form a bridge. You have some nice ideas, but they will not work until you get across.

Title: Re: Cross the river
Post by Icarus on Mar 17^th, 2004, 8:29pm

on 03/16/04 at 17:24:39, Speaker wrote:

Now there ain't no pie-ranny fish in the Platte, which is the only river near here that's too wide ta lassoo across. An it's the only one I suggested walkin' across - it ain't wadin' if the water don't come over yer toes! Any pie-ranny ud have lay on their sides just ta stay wet!

(The Platte, which goes through Nebraska, not Kansas, so "near here" is a bit of a stretch, is an ordinary river for most of its length, but there is a place (or at least was), where it spreads out to great width, but practically no depth.)

Title: Re: Cross the river
Post by Speaker on Mar 18^th, 2004, 1:43am

Okay, this river is not the Platte. Also, there are no piranha in the river actually. But, you need to get the gold without swimming, that is why I put in all the stuff about wading and the current.

But, if anybody trys to swim over to get the gold, then the piranha just might manifest themselves again.

And, while I admire Icarus's skill with a lasso, the river is two wide to throw a rope straight across.

Title: Re: Cross the river
Post by towr on Mar 18^th, 2004, 3:33am

are there trees on both sides of the river?

Title: Re: Cross the river
Post by Icarus on Mar 18^th, 2004, 3:53pm

on 03/18/04 at 01:43:28, Speaker wrote:

And, while I admire Icarus's skill with a lasso, the river is two wide to throw a rope straight across.

It's amazing how skillful you can be when you don't have to demostrate it! :P

Title: Re: Cross the river
Post by SWF on Mar 18^th, 2004, 7:46pm

Tie the boat to a tree with a long piece of rope. The strong current will force it downstream and pull the rope tight. Climb in the boat and use the book as a rudder against the rapidly flowing river to steer it to the other side.

Or: The branches of the trees may be out of reach, but with the rope, climbing to the level of the branches should not be difficult. Then,... well I will wait until this is judged as allowable before I continue.

Or: bring the boat upstream so the bandits see it before they see the gold. Being bandits, they will be unable to resist trying to swim across to steal the boat, and be eaten by the piranhas, giving you time to build a bridge with the hammer, nails, and lumber from the trees on your side of the river.

Title: Re: Cross the river
Post by Speaker on Mar 21^st, 2004, 4:40pm

Towr, there are trees on both sides of the river.

SWF, you are almost there. However, the book is not suitable for a rudder. In fact, you do not need a rudder, if you know the old trick.

I do not think you would have time to climb the tree and cut down a branch because the bandits are coming.

The bandits might end up eaten by piranha, but some will survive.

Title: Re: Cross the river
Post by towr on Mar 22^nd, 2004, 12:25am

well, if there are trees on both banks, then I'd say tie one end of the rope to a tree on your side (around the trunk. Then the other end to the hammer, and flail it around to give it momentum, then swing it into a tree on the other side. Chances are it will eventually get vastened onto a branch, and you can pull yourself and your boat toward the other bank, get the gold, and pull yourself back..

Title: Re: Cross the river
Post by Speaker on Mar 22^nd, 2004, 12:33am

Maybe, eventually it will work if you can throw the hammer far enough. How far can olympic athletes throw the hammer? Then, the river is just a little wider. hehe. ;D

There is a different way, which can be done quickly and surely. It involves the application of certain principles, which I think Icarus is familiar with.

Title: Re: Cross the river
Post by towr on Mar 22^nd, 2004, 1:10am

on 03/22/04 at 00:33:01, Speaker wrote:

Maybe, eventually it will work if you can throw the hammer far enough. How far can olympic athletes throw the hammer? Then, the river is just a little wider. hehe. ;D

Well, the I'd probably still make it, since they can't use rope to swing the hammer, and I can :P

Title: Re: Cross the river
Post by Speaker on Mar 22^nd, 2004, 1:16am

Okay.

But, If I make the river twice as wide, and put the gold on a small island in the middle. Then, the bandits are one side of the river, and you are on the other. So, they can reach the island just as fast as you, if they are trying to snag the hammer in a tree. So, how can you do it faster?

Or, I can just use my godlike powers to remove all the branches from the trees on the other side of the river. :P

Title: Re: Cross the river
Post by kellys on Mar 22^nd, 2004, 11:25am

So I seem to remember (in the dark recesses of me brains) from Physics that if you blow against directly something that's flat, say a piece of paper of just the right size, the air currents will circle around to the back and push it toward you. I also seem to remember something about how windsailing works. Anyways, I'd say that once you're in the boat as described by SWF (and after pulling out your physics textbook) you twist the boat with your body so that its [insert boating term] length is perpendicular with the current. Or maybe something.

Title: Re: Cross the river
Post by Speaker on Mar 22^nd, 2004, 4:16pm

Kellys you are on the right track, along with SWF. All you need now is to apply the correct theory. Maybe what you need is not a physics textbook, but a different kind of textbook. Actually, I have never seen this in a textbook, but then again, the textbooks I have seen are limited. I am sure that the theory is described in some kind of textbook.

Title: Re: Cross the river
Post by kellys on Mar 22^nd, 2004, 4:24pm

hmm... if you were really skilled, you might be able to push the nose of the boat into the water so that it "scoops" the water. The fact that you're propelling mass downstream would mean you would go upstream. Or sink. Probably sink. :)

Title: Re: Cross the river
Post by Icarus on Mar 22^nd, 2004, 4:25pm

I learned about it from a sci-fi novel by Leo Frankowski. I don't remember the exact name, but it was one of his Conrad Stargard books. Conrad is a modern engineer who ends up stranded in Midevel Poland when stumbles into a hidden time machine left open by some less than careful time travelers. He tells this trick to a ferry operator, thus getting himself in deep trouble with the local oarmen who become unemployed as a result.

Title: Re: Cross the river
Post by Speaker on Mar 22^nd, 2004, 4:32pm

I will have to find that book, I love science fiction. It sounds like a variation on "A Connecticut Yankee in King Arthur's Court."

Next, how do you scoop the water?

Title: Re: Cross the river
Post by kellys on Mar 22^nd, 2004, 7:10pm

Punch a hole in the bottom of the boat?

Title: Re: Cross the river
Post by Speaker on Mar 22^nd, 2004, 7:31pm

Only if you want to sink.

Title: Re: Cross the river
Post by SWF on Mar 22^nd, 2004, 7:48pm

Grab the rope, stand up, and lean back a little. It is just like water skiing when you steer well outside the wake of the boat pulling you. Or sort of like flying a kite but horizontally (with you and the boat as the kite).

Title: Re: Cross the river
Post by Speaker on Mar 22^nd, 2004, 7:54pm

SWF, you are correct. The key is that it is like flying a kite. I do not think that you could stand up and do it. So, you need to tie the rope to the boat. The trick is in how you tie the rope.

Title: Re: Cross the river
Post by raven on Apr 15^th, 2004, 8:11pm

Oh darn, and I thought you would tie the boat to your side of the river (to a tree) and chop a tree limb for a push stick... then you would jump in the boat and push it down-river and out in the middle... from here, you simply tie that lasso of Icarus' (using the remainder of the lengthy rope) and lasso the very heavy chest of gold and do a little tight rope walk over to the other side... pull over the boat, dump the chest in, jump in, cut the rope and float down river a rich acrobat... or something of this sort!

;D

Title: Re: Cross the river
Post by Speaker on Apr 15^th, 2004, 11:53pm

Well, you do tie the rope to a tree, then tie the rope to the boat. If you tie it the right way, then the boat should be pulled across the river by the current. Like a wing or a kite is pulled up by the wind. I have never tried it, but I would really like to. There used to be a boat rental place at the river near my home in Tokyo. (It is closed now, a victim of the bubble economy.)

If anybody has a chance to try it, be sure to give us a report. I am curious about what happens as you pay out rope.

Title: Re: Cross the river
Post by Icarus on Apr 16^th, 2004, 4:11pm

The trick is to tie the rope to boat towards the bow, but not at it. The idea is as the boat is pushed against the rope by the current, forces will try to turn the boat so that the point of rope attachment is furthest forward. But this leaves an imbalance of force that pushes the boat away from the side the rope is tied on, so like a kite, it is pushed to the opposite shore. The rope has to be long enough that the boat does not reach it's equilibrium point first.

Title: Re: Cross the river
Post by Speaker on Apr 18^th, 2004, 4:51pm

The way I saw it, in a diagram, was to tie a line from the bow to the stern. Then, tie the long rope to the middle of the bow-stern line. Then when the line is pulled tight, it forms a triangle, with the points being the bow, stern and the tow point where the long rope attaches. This is like the bridle on a kite.

By the way, I went down to the river, and the boat rentel place has moved to the other side. But, it would be difficult to use one of their boats. When you rent a boat in Japan, they keep your shoes at the dock. This is like a deposit, and also keeps the inside of the boat clean. :)