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efreysson
05-14-2018, 01:26 AM
The climax of my Victorian-esque fantasy novel involves a large house being destroyed with dynamite planted in the basement. How much of the stuff is actually required to blow up a house of circa this size?

Or, if not blow it up it outright in one huge blast, then destroy the supports so it collapses?

Also, I have in mind a scene where a character is cornered by enemies and uses the only weapon he has: A stick of dynamite, which he throws into a fireplace his enemies are standing by. Should this set it off immediately?


http://4.bp.blogspot.com/-KbefxQjgM30/UUxZSkNFqII/AAAAAAAAF6k/Mq_LWXH6AH8/s1600/Pinbrook+House.jpg

lonestarlibrarian
05-14-2018, 01:58 AM
I had read that there had been some dynamite/bombings in Victorian London in the 1880's. They'd generally destroy "a cloakroom" or "the ticket office", but probably not a sturdy stone structure of that sort. In my part of the world, you have a string of forts from the 1850's+. They would store their explosives/munitions/etc in powder magazines that look like this:

https://media-cdn.tripadvisor.com/media/photo-s/07/aa/98/5e/fort-belknap.jpg

So if there was ever an accident, the heavy stone walls would absorb the force of the explosion, and the rest of the fort would be safe. So it's very similar to your structure, except, of course, yours has a whole lot more windows. So if an explosion happened in a certain room, I would expect the windows to be blown out--- but if an explosion happened underground, I'd be curious as to how much of the energy would be muffled by the dirt, by the stone, etc.

I live in a house that was built in the 1920's. It was specifically built to be tornado-proof. It has thick concrete walls. I work on stick-built houses that were built in the 1940's. The lumber that was used back then was amazing! So I'm sure there's just as much difference between the solidity of a house that was built in preindustrial times-- late 1700's? early 1800's? --and newbuild that's thrown together with modern lumber.

Have you thought about fire? If I wanted to do something drastic, I'd probably set fire to the drapes in two or three rooms, and perhaps some rugs as well. The weak point is going to be the wooden floors, or the wall paneling. If you can get that to catch, your enemies will immediately reorganize their priorities to keep the fire from spreading, ASAP.

When I had a house fire (tenant doing a midnight moveout by candlelight!) I noticed a distinct difference in how the fire spread, based on whether the doors were open or closed. These were just ordinary hollow core modern doors, but they were sufficient so that there was only really smoke damage in those rooms whose doors had been shut, whereas the fire spread freely through open spaces.

In the meantime, here's an interesting book to page through. It might give you some ideas about explosives. It's The Third Annual Report of Her Majesty's Inspectors of Explosives from 1878 (https://books.google.com/books?id=wv89AQAAMAAJ&pg=RA3-PA123&lpg=RA3-PA123#v=onepage&q&f=false). It's got some interesting reading. :)

frimble3
05-14-2018, 02:13 AM
Imagine the weight of that house: the foundations, the bricks, the chimneys, the floor and roof beams. It's designed to hold all that weight without shifting or collapsing. Even with a mob of people dancing at one end. I'd suspect that bringing it down by explosives would require a engineer, or someone with a lot of experience. It's not a 'man with a crate of dynamite' job.
Although, waving a lit stick of dynamite would probably scare people into leaving.
I agree with Lonestarlibrarian, that setting fire to the woodwork would be a better bet. Keep in mind: a lot of wood polish back in the day was wax based. Layers of it, sinking in over the years. If you can get it to catch, it'll go up, as the saying goes, like a house afire.

efreysson
05-14-2018, 02:36 AM
On the fire idea, for story reasons I need the house destroyed very quickly. The bomber is out to kill a lot of people in one go.

lonestarlibrarian
05-14-2018, 04:19 AM
When was the last time you made a fire in a fireplace? You can go from "just beginning" to "blazing inferno" in almost no time.

If you want a dozen people to be trapped and die, a fire probably won't give you a good result. When people die in house fires, it's usually because there's something else going on. Thinking of some fire fatalities I know-- one was the son of a friend. The fire started. One son alerted the house. Another son had locked himself in his bedroom to keep his brothers out-- and he was rendered unconscious by the smoke before he could get to the door. And no one could get in to save him. By the time the firefighters got to his second-story window, it was too late. Another fire fatality was a client of my husband's. Her uncle took the baby and ran out the back door. She had escaped out the front door, but ran back into the house to get her baby--- not knowing that it had already been rescued. She wasn't able to escape the fire a second time.

However, once a house gets to a certain point in a fire, there's nothing you can do-- and the destruction itself is just a matter of time. If you don't have the equipment to fight it, all you can do is keep it from spreading, and just watch it burn. With Victorian-era firefighting equipment, it might be a day or so before the fire burns itself out, and it might smolder a little longer. My house that burned smelled like charred marshmallows...

So, yes for rapid destruction, but massive casualties don't normally follow under ordinary circumstances. Do you want both those things at once?

jclarkdawe
05-14-2018, 05:43 AM
Take a look at the Oklahoma bombing using 5,000 pounds of ANFO. Now explosions are somewhat unpredictable (a wooden table leg saved Hitler's life) but unless you know exactly where to place the dynamite, you're not going to destroy a building of brick construction very easily. You'd probably need to drill into the foundation to get enough concentration of force. Note that although the exterior walls of the structure might survive, it's hard to say what the internal construction will do. Further, how survival the explosion would be it difficult to predict.

Especially if the dynamite has been in storage for a while, a fire will set it off. Dynamite is unstable and is increasingly unstable as it ages. A typical Victorian room could have several items of furniture that could effect the ability of people to survive in the room. Heavy furniture can distort the blast wave. On the other hand, brick walls would confine the explosive force and concentrate it.

However, remember that a lot of people have their knowledge of explosive force from TV and movies. These consistently understate the amount of explosives needed versus explosive force. MYTHBUSTERS has done a good job of comparing the stated amount of explosive used in the movie versus what you actually need. You can fudge the amount of explosives and make it credible. Further, explosions are unpredictable. Sometimes a small explosion can cause a lot more destruction than is expected.

Jim Clark-Dawe

waylander
05-14-2018, 03:34 PM
Worth remembering that in a house of that age the internal joists etc may not be in the best condition due to dry rot, deathwatch beetle etc so an explosion could collapse the internal features more easily than expected.

WeaselFire
05-14-2018, 06:52 PM
How much of the stuff is actually required to blow up a house of circa this size?

Take the length of a piece of string required to tie two things together in inches, divide by seven and that's the number of sticks required.

Yup. No exact answer possible. But does your novel need a precise amount? Would taking dynamite and putting some at each support column in the basement, tying all the fuses together, lighting them and running suffice? Add in a description of the aftermath, get the outcome you need and you have a story.

Just a note, dynamite of the era is definitely unstable, but fire alone won't normally set it off. If you need that, use black powder charges, which were a lot more common than dynamite (It wasn't invented until the second half of the Victorian era and not in common use until about the late 1880's). Dynamite is nitroglycerin soaked into clay and set off with a blasting cap. Black powder is what you see in the old movies where a villain sticks a fuse into a stick, lights it and throws it.

You could write it so that old black powder storage is under the house in a powder magazine from a previous war. Open the door to the powder vault, pull some casks out into the basement and you could collapse a significant part of the building, crushing a social gathering under the weight of the rubble. No need to bring anything but a match. :)

By the way, the reason those powder magazines were in separate stone buildings in all those old forts has nothing to do with containing an explosion and everything to do with keeping the explosion away from the main fort. Still used today. In fact, black powder storage facilities often use thin plywood or wood slats to contain powder simply so the explosion isn't contained into a more disruptive force.

Jeff

efreysson
05-15-2018, 12:05 AM
Yup. No exact answer possible. But does your novel need a precise amount? Would taking dynamite and putting some at each support column in the basement, tying all the fuses together, lighting them and running suffice? Add in a description of the aftermath, get the outcome you need and you have a story.

A character comes across the crates/barrels/whatever and realises what's going on.


Just a note, dynamite of the era is definitely unstable, but fire alone won't normally set it off. If you need that, use black powder charges, which were a lot more common than dynamite (It wasn't invented until the second half of the Victorian era and not in common use until about the late 1880's). Dynamite is nitroglycerin soaked into clay and set off with a blasting cap. Black powder is what you see in the old movies where a villain sticks a fuse into a stick, lights it and throws it.

Wait, so that isn't actually dynamite? Did folks call that stuff something other than black powder?

Al X.
05-15-2018, 12:51 AM
Dynamite is set off by percussion, black powder is set off by fire. The functionality of the cellulose binder in dynamite is to render nitroglycerin stable enough for transport and handling. Liquid nitroglycerin is so unstable that drops of it will explode on the floor. What makes dynamite go unstable after extended storage is the liquid leaking from the binder and pooling.

As a side note, C4 actually makes a great fuel for small cooking fires. Just don't try to stomp it out.

waylander
05-15-2018, 12:52 AM
Wait, so that isn't actually dynamite? Did folks call that stuff something other than black powder?

Gun powder = black powder

There is also gelignite which was invented by Nobel in 1875 https://en.wikipedia.org/wiki/Gelignite

WeaselFire
05-15-2018, 02:30 AM
Wait, so that isn't actually dynamite? Did folks call that stuff something other than black powder?

Powder charges, mining charges, something like that if not just gunpowder or blasting powder. Might even call it dynamite in later years, though Nobel is who patented that term. Nitroglycerin wasn't even around until about 1850 and nobody knew what to do with it. Dynamite was invented because it's safer than black powder, no small flames setting it off. Nobel's actual useful invention was a blasting cap to set off the nitroglycerin charge. Of course, after a year or two, the nitroglycerin would seep out and make it unstable in regards to bumps and jars. :)

Modern dynamite doesn't even use nitroglycerin because of this, it's usually ammonium nitrate. which is pretty darned safe to handle. And black powder has been illegal to use in the US for mining and blasting for about 50 years.

By the way, TNT and dynamite are two different things. :)

Jeff

blacbird
05-15-2018, 06:55 AM
Be aware of your dates. Dynamite was patented by Alfred Nobel in 1867.

caw

blacbird
05-15-2018, 06:57 AM
As a side note, C4 actually makes a great fuel for small cooking fires.

We often used it in Vietnam to heat up cans of C-ration beans and weenies.

caw

WeaselFire
05-15-2018, 07:49 AM
We often used it in Vietnam to heat up cans of C-ration beans and weenies.

Those were beenie weenies? How could you tell? :)

Had a combat engineer tell me C4 was the stuff my mom had in the Sterno can under the fondue pots.

Jeff

DrDoc
05-15-2018, 11:05 AM
A lot of useful advice here. https://www.google.com/search?q=hagley+mills&rlz=1C1CHYD_enUS598US617&source=lnms&tbm=isch&sa=X&ved=0ahUKEwic8Kb7kIfbAhVSdt8KHdo6CVEQ_AUIDCgD&biw=1920&bih=945#imgrc=p3l_VmJAAD-7UM:http://www.hagley.org/sites/default/files/styles/flexslider_full/public/hagley-birkenhead-mills-and-millrace-print.jpg?itok=EpCD7LM3
This image shows one of the old duPont black powder grinding mills (notice the watermill incenter-left). These exploded frequently and the stone design focused the blast towards the river. All they had to do was build a new roof and repair the twin grinding stones, and possibly hire new people. Rather than collapsing the building you might want to consider collapsing the floor, which would be made of timbers and wood flooring. These are easier to destroy than stone structures.

fwiw
DrDoc

CWatts
05-15-2018, 02:42 PM
You may want to research munitions factory explosions for an idea of the force needed and the casualties.

Richmond, Virginia 1863 - airborne gunpowder dust led to fire that destroyed the (wooden) building and killed dozens of child workers, mostly hours or days later from severe burns. http://www.richmond.com/news/local/city-of-richmond/brown-s-island-munitions-explosion-was-worst-wartime-disaster-in/article_9683aac6-847f-11e2-b033-0019bb30f31a.html

Stowmarket, East Anglia, England 1871 - this was a brick building and looks like the devastation you describe. They manufactured guncotton that may have been sabotaged.
http://eastanglianlife.org.uk/resource-type/explosion/

Quinn_Inuit
05-16-2018, 06:38 AM
Unless you have a ton (literally) of dynamite, you really need to have some engineering background to level a large brick house with dynamite. You've got to know where the structural load is concentrated, hit that, and make sure it blows out in the correct direction.

Al X.
05-16-2018, 06:43 PM
Wiki says that the first hollow shaped charges appeared around 1863 using gunpowder. In the modern day we would be looking at conical shaped charges placed at key structural supports.

DanielSTJ
05-17-2018, 05:26 PM
Just wanted to say that this sounds like a cool idea!

Rock it! :)

neandermagnon
05-18-2018, 09:37 AM
Unless you have a ton (literally) of dynamite, you really need to have some engineering background to level a large brick house with dynamite. You've got to know where the structural load is concentrated, hit that, and make sure it blows out in the correct direction.

I was going to say something along these lines. There are demolition experts that demolish old buildings. It's not so much about the amount of dynamite, it's more about putting it in the right places to a) destroy the right bits to weaken the structure in the right places, b) ensure that the whole building is destroyed and not just bits of it and c) cause it all to fall inwards rather than explode outwards to avoid damage to the surrounding area.

As far as plausibility goes, if the building isn't being deliberately demolished, I'd find it unlikely it would be completely destroyed (as opposed to having a chunk blown out of it) without sufficient explanation, e.g. the dynamite happened to be placed in such a way that it took out the internal supports of the building so the whole thing fell down. Even then, without a demolition expert, even with a huge amount of dynamite, bits of it might still be left standing, or might fall down much later due to erosion or whatever.

Old buildings can become structurally unsound without any explosion, e.g. due to subsidence. Structural engineers can sometimes fix buildings that aren't too badly affected by this to prevent them from falling down, however it's not always possible and buildings have to be condemned and they are usually demolished so they fall down in a controlled way rather than randomly which could endanger life - they will fall down in the end, if left alone. If the building is already structurally unsound then it's not going to take all that much to make it fall down. I still wouldn't trust anyone but a qualified person to make it fall down. But for story purposes, someone for whatever reason putting dynamite in the basement or wherever might be enough to start the whole falling down process off. And if you want damage to the surrounding area and endangerment to life to be part of the plot, it would work.

Frenzy3
05-18-2018, 03:11 PM
Reading through this say 4 barrels of black powder. Even if the house still standing the occupants would most likely have died.

efreysson
05-21-2018, 03:09 AM
Oh, I forgot to ask something:

I've pretty much shifted into using black powder, packed into paper tubes, in place of actual dynamite. But I have a character carrying a few sticks to use as weapons. Can he make them more deadly simply by attaching a lot of metal nails to the surface?

blacbird
05-21-2018, 05:37 AM
Oh, I forgot to ask something:

I've pretty much shifted into using black powder, packed into paper tubes, in place of actual dynamite. But I have a character carrying a few sticks to use as weapons. Can he make them more deadly simply by attaching a lot of metal nails to the surface?

Absolutely. Shrapnel is extremely nasty. The Boston Marathon bombers did exactly this, packing around their explosives a pile of such shrapnel and jamming all of it into pressure cookers. Three deaths, dozens injured, many with amputations.

caw

frimble3
05-21-2018, 05:55 AM
Trouble is, if your character makes these paper tubes of dynamite-surrounded-by-shrapnel, and just throws them, he's likely to be one of the casualties.

efreysson
05-21-2018, 10:31 AM
Trouble is, if your character makes these paper tubes of dynamite-surrounded-by-shrapnel, and just throws them, he's likely to be one of the casualties.

I'm planning a scene where he throws it around a corner.