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Marian Perera
03-20-2014, 05:43 PM
Hey everyone,

So this is a later scene in my iceberg story. What's happened so far: a sailing ship has become trapped against an iceberg which has sprouted two "arms" of ice around the ship. The arms join and the ship is left floating in a little lake, unable to breach the ice.

The villain, who's hiding on the berg, wants to seize the undamaged ship. He causes more ice to grow up around the ship, so now it's like the ship's inside a giant snow globe. He might also start smoke materializing inside the globe, to suffocate the crew.

I was thinking of the crew using their cargo of flour and the confined space to cause an explosion. If, from the deck, they created a cloud of flammable material and ignited it, could that break the globe? I don't mind pieces of the yardarms or gunwale flying in all directions, to smash through the ice.

My other question is, how much flour might they need? Just a ballpark idea would do.

Thanks muchly. :)

Helix
03-20-2014, 05:48 PM
I can't answer the question, so I'll cause a distraction by asking how they are going to keep safe from the explosion.

Marian Perera
03-20-2014, 05:52 PM
I can't answer the question, so I'll cause a distraction by asking how they are going to keep safe from the explosion.

Hide in the hold?

At this point they figure they have nothing to lose (the villain's magic is pretty powerful), so they might as well fight back even if it means risking their lives. They also know that he needs an undamaged ship to get him off the berg, so they won't really mind if a mast comes down.

Helix
03-20-2014, 05:57 PM
Would the hold be full of flour dust? Might get a bit ugly! Could they fashion a cannon out of something and use flour as propellant?

Sorry, QofS. I'm just thinking out loud here because I'm not able to provide any real help. (And I'm procrastinating.)

Marian Perera
03-20-2014, 06:01 PM
Would the hold be full of flour dust?

Would it? I was under the impression that flour would be shipped tightly packed, to reduce the amount of oxygen available to the particles and the likelihood of an explosion.

Even if that isn't the case, I can always have the hold divided in two : one part for the flour and the second for the other types of cargo.


Might get a bit ugly! Could they fashion a cannon out of something and use flour as propellant? That might take some time. I'd like to have everything happen quickly after the globe appears, because the villain won't be sitting back and waiting patiently while they build a cannon. He wants them dead fast.


Sorry, QofS. I'm just thinking out loud here because I'm not able to provide any real help. (And I'm procrastinating.)No problem. :)

Torgo
03-20-2014, 06:05 PM
Looks like dust explosions (http://en.wikipedia.org/wiki/Dust_explosion) can be pretty powerful. What I would worry about on a ship, though, is that they create huge fireballs, and that's about the last thing you'd want if it was wooden.

Mythbusters did some experiments with this - google 'creamer cannon', it's kind of fun - but I think it might be tough to get enough bang to break through walls of ice and not blow the ship to bits.

mirandashell
03-20-2014, 06:09 PM
You wouldn't need to blow up the ice though, would you? You just need enough force to cause a big crack in it and then it will fall apart under its own weight? Or am I talking out of my bum?

Marian Perera
03-20-2014, 06:14 PM
Hmm. I wonder if I could have the explosion inside a barrel, which would propel whatever was inside out at a speed that might break the ice. Unfortunately, no compressed air. I don't mind a fireball, though - most of the crew won't be on the deck and they'd rather destroy the ship than allow the villain to seize it.

Marian Perera
03-20-2014, 06:16 PM
You wouldn't need to blow up the ice though, would you? You just need enough force to cause a big crack in it and then it will fall apart under its own weight?

Even a big crack would provide air to the crew, meaning the villain couldn't suffocate them. I just want something a little more dramatic than the crew chipping away at the ice with pickaxes while the villain's not doing anything.

mirandashell
03-20-2014, 06:20 PM
Hmm... doing it in a barrel would be tricky, wouldn't it? I thought it was the flour particles being in the air that was the problem, not compressed flour in a barrel?

I think throwing a lot of flour in the air and igniting it with fire arrows to cause a big crack and the ice cracking like windscreen glass around a stone chip would be pretty spectacular. And a lot quicker than chipping, I think.

Marian Perera
03-20-2014, 06:24 PM
Hmm... doing it in a barrel would be tricky, wouldn't it? I thought it was the flour particles being in the air that was the problem, not compressed flour in a barrel?

I was trying to figure out how to get shrapnel into the air and moving at high enough speed to break through the ice, but if your idea works that would be fine. The crew has a small catapult on board which they were using to try to smash through the "arms", except the villain defeated that plan by just growing an ice globe around them, and they've used up their projectiles.

What they still have, though, is the flour. If they were able to suspend all that flour in the air and then ignite it with a fire arrow (nice touch!) and the ice cracked, that would be fine with me. Even if the sails or yardarms ignited, the heat would just weaken the globe further.

Helix
03-20-2014, 06:25 PM
What about attaching sacks of flour to the masts or filling the furled sails with flour and then rigging* some sort of fuse that opens the sails and ignites the suspended particles?

* arf arf

mirandashell
03-20-2014, 06:31 PM
Both ideas sound good. A fireball is always a good thing in a fantasy novel!

Well... not for the characters but you know what I mean! LOL!

mirandashell
03-20-2014, 06:34 PM
Thinking about it, depending on the amount of floor, the fireball could be massive. If you could throw a lot of barrels up, they all break at roughly the same time, air full of flour....3 or 4 fire arrows in different directions.... HUGE bang!

Marian Perera
03-20-2014, 06:39 PM
I have no problems at all with a bang that echoes across the stretches of the iceberg like a boom o' doom.

The villain can be most disconcerted to realize that the heroes fought magic with science. :)

mirandashell
03-20-2014, 06:40 PM
Sounds good to me!

jclarkdawe
03-20-2014, 07:52 PM
Here's a report from the International Ice Patrol:


On May 1, 1925, eight men on the US Coast Guard cutter the Tampa climbed into a lifeboat, rowed 500 yards through waves in the treacherous North Atlantic Ocean, boarded a large iceberg drifting silently in the Labrador Current, and planted a floating mine at the edge of the ice. The International Ice Patrol, a US Coast Guard division with 14 participating nations that was set up after the Titanic sank in 1912, was conducting iceberg demolition experiments over the Grand Banks of Newfoundland, near the world's busiest
shipping lanes and some of earth's richest fishing grounds. The small group from the Tampa maneuvered their lifeboat away from the iceberg as they ran a hundred yards of wire from the mine on the berg's ledge to their precarious position bobbing in the waves. And then, as officers and crewmen from the
Tampa's deck watched and took photographs, they detonated the mine. A spectacular geyser of ice, water, and smoke shot into the air and sent out small waves toward the boats as bits of ice peppered the area. The men in the lifeboat rowed back to the Tampa, climbed aboard, and moved on. A few hours later, they approached another berg and converted it into a "shooting gallery." The crew pounded the iceberg with thirty rounds of three-inch artillery shells. Despite sounding farfetched, dangerous, and even ridiculous, the Ice Patrol had noble intentions with these iceberg explosions: they hoped
to hasten the demise of bergs before they floated directly into the steamship lanes and created a menace for international shipping and transportation. They were trying to ensure that another Titanic catastrophe never again occurred.

The main problem with bombing bergs is that it just didn't work. Not even close. And it was dangerous. But it to ok the Coast Guard's Ice Patrol nearly a half century to figure that out definitively. The typical outcome of iceberg warfare was what Coast Guard yeoman Leo Shubow witnessed with these two assaults in 1925. The impact of the mine planted by the Tampa, he concluded, was "unnoticeable." And "after all this hubbub and shooting" at the second iceberg, Shubow asked: "What happened to the berg? Only a few chunks had been shaved off the ends, but the berg proper seemed to remain impregnable and adamant. Nature itself would have to be more cooperative in undoing these icy mountains through rain, fog, surging waves, and the approaching warm Gulf Stream." In fact, Shubow was more insightful and forward-looking than he might have imagined. Almost forty years later, the International Ice Patrol finally abandoned a half century of experimenting with iceberg obliteration.


You crew would do better to take an ax to the hull.

Best of luck,

Jim Clark-Dawe

mirandashell
03-20-2014, 08:05 PM
It's not a berg, though. It's a dome.

Marian Perera
03-20-2014, 08:13 PM
It's not a berg, though. It's a dome.

Yes, unless a dome of ice (which is not solid beneath the dome) behaves just the same as an iceberg which is solid all the way through, I'm sure a detonation under it would have some effect.

If the crew takes an axe to the hull, they're probably all going to die. I don't mind them being prepared for that outcome, but the story will end if they all do actually bite it. So if a dome reacts just the same as an iceberg, then I'll have to scrap this idea.

King Neptune
03-20-2014, 10:17 PM
I have read about large flour explosions, and they can be huge. The problem would be getting enough flour floating in the air. If your crew can get a ton of flour into the air and put fire to it, then there would be a substantial explosion. I suspect that most readers will accept that as a possibility, and that's what's important. If this were the real world, then I would worry about broken eardrums and other such injuries.

jclarkdawe
03-20-2014, 10:18 PM
Unless the doom is ready to collapse, which does happen as ice melts, it's not going to make much difference. A surface explosion against ice is like a surface explosion on a rock surface. In other words, you don't get much damage.

An explosion in ice, where you have drilled into the ice and inserted the explosive, can be more effective, but ice is just hard to deal with.

Best of luck,

Jim Clark-Dawe

mirandashell
03-20-2014, 10:20 PM
But what about a fireball? Would that work? If it melts enough for weak spot to appear there could then be a crack? And the dome doesn't necessarily have to be very thick if the idea is suffocation.

King Neptune
03-20-2014, 10:21 PM
The pressure from an explosion could easily crack something as brittle as ice. I don't know how big the dome is, but increasing the pressure for a half second should work.

Marian Perera
03-20-2014, 10:22 PM
Unless the doom is ready to collapse, which does happen as ice melts, it's not going to make much difference. A surface explosion against ice is like a surface explosion on a rock surface. In other words, you don't get much damage.

I'm leaning towards the "fling a crate of flour into the air and ignite the flour as it bursts out" method, but I could always have pieces of metal in the crate with the flour. I doubt a ship would be carrying caltrops, but they were expecting a boarding party. They should have some kind of pointed metal around.

If even sharp, hot metal being propelled against ice at speed makes no difference to the ice... then I guess I'll just have to take my chances with the readers buying the scenario.

jclarkdawe
03-20-2014, 11:28 PM
Literary license is a wonderful thing. All you want to know is when you're using it.

Best of luck,

Jim Clark-Dawe

Maythe
03-21-2014, 12:27 AM
This is something of a side point but the size of the ice crystals would make a big difference to the strength of the ice wouldn't it? Since this is magically induced ice the individual ice crystals could be huge and so the 'cracks' between them where they meet would be quite vulnerable. Just as it's easier to scrape the ice off my car when the ice formed slowly and the crystals are big, rather than when they formed quickly and are very small.

frimble3
03-21-2014, 01:30 AM
!) Wouldn't a fireball big enough to burst/crack/mess with a magic ice dome also use up a lot of the oxygen inside the dome? So unless it worked immediately, it could be as dangerous as the fire that follows, especially if the air is full of flour particles, which means the flour-fire would be everywhere.
2) Is the ice dome floating on the water or on the same ice-floe the ship is trapped in? As I see it, the problem with the attempts to shoot or blow up icebergs is that they are loose and floating, and able, if not to duck, then to bob away from the shot/blast. If the ship and the dome are frozen into one unit, you might have better luck.

mirandashell
03-21-2014, 01:43 AM
Well that would make it more dramatic, wouldn't it? How close to death will they get? How many will die? Who will survive? Reader on the edge of her seat?

Netz
03-21-2014, 02:23 AM
:nothing You always ask such interesting questions in this forum, Queen of Swords! :D

NeuroGlide
03-21-2014, 02:54 AM
You're going to need compressed air. You have to blow the powder into the air at fairly high speed to get the flour aerosolized for ignition. Here's how to do it. Get some heavy lead piping, say 6 inch septic line, with a cap on one end and a reducer connection on the other. Put a thin metal sheet, copper should be available, on the inside of the connector. Drill a hole in the bottom of the barrel and mount this on the outside. Inside the barrel, put in a metal funnel attached to the connector (not essential, but helps direct the blast). Now you need an ignition source in the piping and a way to inject fuel. When the fuel ignites, pressure will spike until it ruptures the burst disk (the copper). It will the rush out at high velocity, pushing the flour up into the air. It may not ignite the flour on it's own, but a flare in the flour barrel will insure that. Mythbusters did some thing similar with non-dairy creamer. They didn't have enough pressure so a lot of creamer didn't ignite. It was still the largest fireball they ever produced.

Link: https://www.youtube.com/watch?v=yRw4ZRqmxOc

Marian Perera
03-21-2014, 03:04 AM
!) Wouldn't a fireball big enough to burst/crack/mess with a magic ice dome also use up a lot of the oxygen inside the dome? So unless it worked immediately, it could be as dangerous as the fire that follows, especially if the air is full of flour particles, which means the flour-fire would be everywhere.

You're right, it would use up a lot of the oxygen inside. But I also figure that would make the flames short-lived, wouldn't it? And the crew isn't going to be suffocating on the deck; there's trapped air inside the ship and I'm guessing most of them will be inside. By the time they start to feel the effects of that, the dome should have cracked or started to melt.


2) Is the ice dome floating on the water or on the same ice-floe the ship is trapped in? As I see it, the problem with the attempts to shoot or blow up icebergs is that they are loose and floating, and able, if not to duck, then to bob away from the shot/blast. If the ship and the dome are frozen into one unit, you might have better luck.

Then I'll go with frozen into one unit. :)

I'm pretty flexible on how this happens, as long as it happens.

Marian Perera
03-21-2014, 03:08 AM
Get some heavy lead piping, say 6 inch septic line, with a cap on one end and a reducer connection on the other. Put a thin metal sheet, copper should be available, on the inside of the connector.

I saw the Mythbusters video. It was great.

That said, this is a sailing ship at the start of the Age of Steam, without any weaponry on board, let alone the time or the knowledge to build such a device. So the crew has to go with a catapult (something they could have built previously to break through the "arms" of the iceberg) tossing a crate of flour against the dome. Crate splits, flour aerosolized, fire arrow, boom.

It won't be as scientific as the Mythbusters experiment, but what other options do I have?

Marian Perera
03-21-2014, 03:10 AM
You always ask such interesting questions in this forum, Queen of Swords!

Thanks!

What can I say, I have lots of unusual scenarios in my books. :)

frimble3
03-21-2014, 03:14 AM
Reading this thread all the way through, from the beginning, very slowly, I have an alternate to the 'flour explosion'. Not as dramatic, not as exciting, but:
Apparently the magic ice acts like real ice, in that it melts. This is a wooden sailing ship? I'm assuming that somewhere in the ship's supplies there's a barrel (one at least) of tar for emergency repairs. (Probably kept near the spare spars, and planks, and rope).
Have the crew row the barrel of tar out to the edge of the dome, where the dome hits the ice, or the water. (If the edge of the dome is sitting on the water, have them make a small raft.) Have them shove the barrel right against ice, and light it. Tar burns, pin it in position, let it burn at least an airhole/vent in the dome. The hole might even weaken the dome enough for the shifting tensions to crack it (like a small hole in a windshield leads to cracks).

NeuroGlide
03-21-2014, 03:22 AM
I saw the Mythbusters video. It was great.

That said, this is a sailing ship at the start of the Age of Steam, without any weaponry on board, let alone the time or the knowledge to build such a device. So the crew has to go with a catapult (something they could have built previously to break through the "arms" of the iceberg) tossing a crate of flour against the dome. Crate splits, flour aerosolized, fire arrow, boom.

It won't be as scientific as the Mythbusters experiment, but what other options do I have?

Does it have a steam engine? Or does it carry parts for one, maybe as cargo? Those parts would be perfect for what I described. And they certainly have lantern oil onboard.

Marian Perera
03-21-2014, 03:26 AM
Hey, that's not bad, frimble3. Thanks! :)

And tar is definitely something they would have on a soon-to-be-decommissioned sailing ship during the early days of the Age of Steam.

Now I'm thinking of having the crew use the tar to melt the other ice, the arms enfolding them. They can have the catapult as well, but given how thick the arms are, burning tar would help so much. Plus, at first they're out in the open, so why not start a fire? The smoke might attract attention during the day, too.

Then, just when they've opened a breach with this excellent tactic, the dome appears around them.

Marian Perera
03-21-2014, 03:31 AM
Does it have a steam engine?

No, unfortunately. It's the early days of the Age of Steam and this is one of the older models (a sailing ship) that's soon to be scrapped. I think this is the second-to-last book I'm going to write with sailing vessels. After the next one, I want everyone caught up to steam.

Technically the ship could be carrying steamship parts and they'd certainly have lantern oil, but the level of expertise it might take to build the cannon you mentioned... I'm not sure anyone on board a sailing ship, especially one that doesn't even have weaponry of its own, would have gained that kind of knowledge from their daily work.

I do love chemical explosions and blowing things up good. I'm just not sure how to work that kind of specialized skill into the story.

frimble3
03-21-2014, 03:37 AM
Hey, that's not bad, frimble3. Thanks! :)

And tar is definitely something they would have on a soon-to-be-decommissioned sailing ship during the early days of the Age of Steam.

Now I'm thinking of having the crew use the tar to melt the other ice, the arms enfolding them. They can have the catapult as well, but given how thick the arms are, burning tar would help so much. Plus, at first they're out in the open, so why not start a fire? The smoke might attract attention during the day, too.

Then, just when they've opened a breach with this excellent tactic, the dome appears around them.
And, on a flattish surface as I'm supposing the arms are, they could warm the tar and spread it in a thick layer, rather than keeping it in the barrel (against the curve of the dome, spread-out tar would only slip off, as the ice under it melted.
It would also explain why their opponent upped the ante with the dome, if they had already breached the arms, or were about to.

NeuroGlide
03-21-2014, 05:40 AM
Technically the ship could be carrying steamship parts and they'd certainly have lantern oil, but the level of expertise it might take to build the cannon you mentioned... I'm not sure anyone on board a sailing ship, especially one that doesn't even have weaponry of its own, would have gained that kind of knowledge from their daily work.

Then I have a logic question. Where did they come up with the idea of using the flour as an explosive? When most people consider flour, it's explosive potential does not come to mind. You've pretty much established their "think outside of the box" cred right there.

mirandashell
03-21-2014, 01:37 PM
The cook on board. He could have been a baker before he joined the ship and could have had experience of combustible particles.

Marian Perera
03-21-2014, 03:12 PM
Then I have a logic question. Where did they come up with the idea of using the flour as an explosive? When most people consider flour, it's explosive potential does not come to mind. You've pretty much established their "think outside of the box" cred right there.

Maybe it's a stretch that the crew of a cargo ship know about certain precautions to be taken when transporting flour in the hold.

But IMO it would be as much of a stretch for them to know about a cap, a reducer connection, how to direct the blast with a metal funnel and how to inject fuel, though I'm sure every ship has a barrel with a hole in it. That seems pretty specialized knowledge. I'd have to look up diagrams of it to be confident I was describing it correctly, so unless I establish beforehand that one of the crew has this MacGyveresque background, I can't really see them putting this together.

For comparison purposes, in a previous chapter they were happy they managed to build a catapult. That's pretty much the limit of their engineering skills.

The cannon is a really clever idea and I'm glad you explained it clearly, because I might want to use it in another book. But unless there's something egregiously wrong about their catapulting a crate of flour at high speed against the dome and igniting the resulting dust cloud, I'll have to go with that lo-tech solution.

NeuroGlide
03-22-2014, 02:07 AM
Alright, the effects of a catapult launch of flour. Flour is usually shipped in bags. Large shipments will be stacked on pallets. Reference. (http://www.cargohandbook.com/index.php/Flour) The bags will need to be scored with a knife to ensure bursting upon striking the ice. The fire arrow (or a flare gun (http://wiki.answers.com/Q/When_was_the_first_flare_gun_invented)) will ignite the outer most dust explosively, but the main bulk will be too dense to explode and just burn fiercely until it strikes either the ice or water.

mirandashell
03-22-2014, 02:10 AM
Sailing ships would not have transported flour in gunny sacks at the time this story is set.

Having said that, I'm finding it difficult to find out what the flour would have been in.....

NeuroGlide
03-22-2014, 02:27 AM
Sailing ships would not have transported flour in gunny sacks at the time this story is set.

Having said that, I'm finding it difficult to find out what the flour would have been in.....

I found a barrel reference, but for 1770s.

mirandashell
03-22-2014, 02:29 AM
Then I think it could work for the scene. It doesn't need to be that historically accurate. We are talking about a way of breaking a magic ice dome.

:D

Marian Perera
03-22-2014, 02:35 AM
I found a barrel reference, but for 1770s.

I don't mind going back to the 1770s. The story is set in about the early 1800s, but since it's an alternate world fantasy - and since it's been established that this is an old ship that can just about manage short-haul cargo runs - things on board are probably even more outdated.

NeuroGlide
03-22-2014, 02:46 AM
I don't mind going back to the 1770s. The story is set in about the early 1800s, but since it's an alternate world fantasy - and since it's been established that this is an old ship that can just about manage short-haul cargo runs - things on board are probably even more outdated.

Well, it's the shipper that would pack it so it's what ever they would use. While searching on gunny sacks was dry for dates, Gunny Cloth gave me a hit for early 1800's, so it's what you will.

jclarkdawe
03-22-2014, 04:20 AM
Probably shipped in barrels, but Hornblower deals with a boat loaded with rice in sacks so it's plausible to be in sacks.

Barrels would be watertight, and the deck would have leaked from any seas shipped over the bow.

However, I'm not sure that flour was shipped that much back then. It's heavy, short shelf life if wet, and cheap, and was produced locally.

Something more likely to be shipped, and much more explosive would be coal. A ship that had transported coal and was heading back for more would have tons of coal dust in its hold. Coal dust is viewed as a possible, though not probable cause for the second explosion.

Best of luck,

Jim Clark-Dawe

Marian Perera
03-22-2014, 02:59 PM
Something more likely to be shipped, and much more explosive would be coal. A ship that had transported coal and was heading back for more would have tons of coal dust in its hold.

Really? There'd be a lot of dust even if there was no actual coal?

That would be fine for my purposes too. :)

jaksen
03-22-2014, 05:16 PM
I would think, that no matter how you do this, you have your characters discuss/argue/talk about the very things that are in this thread. At least a little. They wouldn't necessarily 'know' how to do this, either. Maybe they make one or two blunders before succeeding?

Either that or they are smarter than everyone on this thread. :D

jclarkdawe
03-22-2014, 05:24 PM
Coal dust is a pain in the butt even now. For railroad transport, you have to run the train under sprayers to wet down the coal and cut the dust to an acceptable level. Otherwise it blows all over the place as the train rolls through the countryside.

Look up "colliers," which was the name for these types of ships. Explosions were not unusual. Especially in the early days of steam, there were a lot of wooden ships that were converted to transport coal.

The coal industry spends a lot of money on convincing us coal is a "clean" fuel, but it's "clean" only with a lot of effort.

Best of luck,

Jim Clark-Dawe