Moderated Discussion Areas
  ContinuousWave: The Whaler GAM or General Area
  Buoyancy Problem and 55-Gallon Drum

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Buoyancy Problem and 55-Gallon Drum
elaelap posted 11-17-2009 05:32 PM ET (US)   Profile for elaelap   Send Email to elaelap  
Engineers and physics cognizanti, I appeal to you for help with this problem:

I'm re-reading Vincent Bugliosi's fascinating real life sea story/murder mystery, "And the Sea Will Tell." It's the tale of two couples who travel to Palmyra Island, about a thousand miles south of Hawaii, in two very different cruising sailboats, interact there for a couple of months, and only one couple returns, in the other's boat. That couple is eventually charged with theft and murder, and Bugliosi (who earlier as a deputy prosecutor successfully conducted the Charles Manson trial for the People), takes the defense this time of one of the accused. An absolutely great read, BTW, both for lawyers and for those who love boats and the sea.

Anyway, I've come upon the following footnote in that book, and it makes no sense to me whatsoever; thus I seek clarity from the scientists at this website:

"Mobster Johnny Roselli, involved in the CIA-Mafia plot to assassinate Cuban premier Fidel Castro, was murdered in 1976, stuffed into a fifty-five-gallon oil drum weighted down with heavy chains, and dumped into Miami's Biscayne Bay. Fishermen discovered the drum when decomposition gases produced enough buoyancy to float it to the surface just ten days later." [My emphasis]

My question: How on earth could change in the physical properties of a human body--or any other object for that matter--in a closed, air-tight environment such as a 55-gallon drum have changed the drum's buoyancy? (I guess I could see how this might happen in an expandable drum made of rubber or some other such substance, where the volume of water displaced in relationship to the weight became larger as the gases expanded, but how could this be possible in an oil drum?)

Thanks, and please respond on level that a not-exceptionally-bright sixth-grader might understand.


elaelap posted 11-17-2009 05:35 PM ET (US)     Profile for elaelap  Send Email to elaelap     
Whoops. Shoulda only been one 's' in "gases" in the topic heading. Sorry
deepwater posted 11-17-2009 05:43 PM ET (US)     Profile for deepwater  Send Email to deepwater     
Inside the human body are bugs that make farts (gas) and when the body dies it turns into one big fart,,^@^,,Simple enough?
Jerry Townsend posted 11-17-2009 06:53 PM ET (US)     Profile for Jerry Townsend  Send Email to Jerry Townsend     
Tony - you read too much fiction. In your case, the body would decompose to some level - but the lack of oxygen slows/stops any further decomposition. But in the engineering world, a fundamental law basically states that mass is conserved - therefore, since an exchange of mass cannot occur, the stuff you read is, well - stuff. --- Jerry/Idaho
elaelap posted 11-17-2009 07:24 PM ET (US)     Profile for elaelap  Send Email to elaelap     
While I love good fiction--you should try some yourself, Jerry--this 657-page book is factual, and the second half is primarily made up of the actual trial transcripts with the author's (the defense attorney's) commentary.

Your response to the science question is what I expected, and with my tiny bit of knowledge of physics and chemistry is what I imagined to be true, which is why I asked. Unless whatever gases were produced caused that oil drum to bulge considerably, somehow stretching the metal, it wouldn't make any difference at all what the composition of the elements inside the drum, right? If it sank initially and stayed the same size, its weight wouldn't change at all even if the body produced hydrogen or helium.

I wonder how the author, editor and publisher got it so wrong.


jimh posted 11-17-2009 07:24 PM ET (US)     Profile for jimh  Send Email to jimh     
The 55-gallon drum has a particular volume. In order to sink, the weight of the drum and whatever is inside has to be greater than the weigh of the water displaced by the drum. If we assume the drum is tightly sealed, then nothing can escape from the drum. No mater what chemical reaction takes place, there will be no change in mass inside the drum.

On the other hand, if the drum leaks, then we could have a situation where inside the drum the decomposition of the body would built up pressure. At some point the pressure would be great enough to create a leak, and gas would escape. As the body decomposes, more of it would be converted to gas which then escapes. We need the leak to be a sort of one-way leak so that water does not enter. If the pressure of the gas is always greater than the pressure of the water, then the leak would always tend to let gas escape but to prevent water from entering. At some point enough of the body has decomposed into gas, which has escaped, that the total weight of the drum is now less than the weight of the water it is displacing, so the drum has buoyancy.

hauptjm posted 11-17-2009 07:28 PM ET (US)     Profile for hauptjm    
Bugliosi has always been given to extreme fantasy, ego and grandstanding, but he always makes for interesting reading. I've read some of his work quite a while back, so I may have to reacquaint myself with "And the Sea Will Tell."
crabby posted 11-17-2009 07:36 PM ET (US)     Profile for crabby  Send Email to crabby     
If the drum were not truly airtight (it's usually a bandclamp that holds the top on and these are not necessarily a good sealing device) the drum could have filled with water as it settled. If it settled with the top side down, then, as the body decomposed, gases produced by the bacteria decomposing the body may have displaced the water by forcing it back out of the "seal" around the lid.

A cubic foot of water weighs a little over 64 pounds. A 55 gallon drum would displace about 7.3 cubic feet. 7.3 times 64 = 470. This implies that a sealed 55 gallon drum and it's contents would need to weigh more than 470 pounds to sink. So if you take the weight of the drum (say, 50 pounds), add the weight of the deceased (200 pounds?), add some chain (another 200 pounds?) and you have 450 pounds, not enough to sink but if you add some water you could have enough to sink it. Now if some of that water is displaced by the gases produced by decomposition the drum will no longer sit on the bottom.

elaelap posted 11-17-2009 07:37 PM ET (US)     Profile for elaelap  Send Email to elaelap     
I don't know much about Bugliosi outside his legal career, hauptjm, and this book was written back in 1991, but I assure you it's a great read (especially the first part for non-lawyer sailors; the second half is mostly pretty detailed trial strategy and tactic minutiae, which might well bore the pants off a layperson).


I'm reading the Ballantine/Ivy Books True Crime paperback, BTW, which can be picked up for a song in any decent used book store. It was apparently the #1 New York Times bestseller for a while after its publication.

deepwater posted 11-17-2009 07:45 PM ET (US)     Profile for deepwater  Send Email to deepwater     
I liked the fart example,,You did say 6th grade level
R T M posted 11-17-2009 08:14 PM ET (US)     Profile for R T M    
[Too much faux New Jersey machismo; probably from watching too much HBO entertainment television. Deleted--jimh]
dfmcintyre posted 11-17-2009 10:21 PM ET (US)     Profile for dfmcintyre  Send Email to dfmcintyre     
Easiest explanation is that some of the chains came off. Here's why:

Assuming the decomp scenario, you'd also have to have someway to displace liquid for the gas to expand. And as explained in previous posts, it's not going to happen (beyond a slight amount of oxygen in the container to begin with).

Gas would raise pressureinside the barrel and force liquids (or solids) out. But any slight change in attitude, you could easily have the gas escaping instead of liquid. And since the solid (body, no matter what state of decomp) would weigh more, the heavy end of the barrel would go down.

About 20 years ago, we had a homicide up here where a diver was drift diving about 40' off shore in 30' of water in the St. Clair River, just south of the Blue Water Bridge. Struck something, turned around and came pretty much face to face with a guy who'd been tied to a couple of cement blocks and tossed in the river. Some sort of gypsy organized crime boss and I think the case is still unsolved. Called him "Bob" for a while...


Hoosier posted 11-18-2009 08:15 AM ET (US)     Profile for Hoosier  Send Email to Hoosier     
If the fill hole in the drum was left off then the water would have had a way to get into the drum while sinking. If then after hitting the bottom the drum inverted so that the fill hole was downward, then there would be the scenario we're talking about. There's a way for the water to be pushed out and the gas is still captured in the drum.
Tohsgib posted 11-18-2009 10:11 AM ET (US)     Profile for Tohsgib  Send Email to Tohsgib     
Sorry but bodies do not bloat that much when they decompose. They get puffy but they don't turn into a Macy's Parade baloon.
R T M posted 11-18-2009 11:25 AM ET (US)     Profile for R T M    
[Too much faux New Jersey machismo; probably from watching too much HBO entertainment television. Deleted--jimh]
Tohsgib posted 11-18-2009 11:47 AM ET (US)     Profile for Tohsgib  Send Email to Tohsgib     
If decomposition gases were that powerfull, every dead fish in the world would be floating and not crab bait.
Buckda posted 11-18-2009 11:54 AM ET (US)     Profile for Buckda  Send Email to Buckda     
Nick -

You're forgetting the confined space that the body is in.

True that bodies and dead fish don't always bloat too much, but if there is any wound (as Binkie mentions) that allows gas to vent, that explains a lot of it - and even then, it is venting into open "atmosphere" (or ocean) - not a confined space such as a 55 gallon barrel in the above example.

R T M posted 11-18-2009 12:50 PM ET (US)     Profile for R T M    
[Too much faux New Jersey machismo; probably from watching too much HBO entertainment television. Deleted--jimh]
Tohsgib posted 11-18-2009 01:31 PM ET (US)     Profile for Tohsgib  Send Email to Tohsgib     
If you sealed it with air in it I doubt it would sink, especially in salt water. Beercans will float if unopened in salt water. The only way it would sink is if it filled with water and even then it might take a little "persuasion" like Binks mentioned. Take a coffee can and stick a dead rat in it and experiment in your hot tub, I think you will find similar results. Body in a drum is a bad idea in that it will never fully decompose to where it can't be identified. Many people have tried that and it backfires. You want the crabs or wild hogs to eat the evidence...especially the teeth.
Tohsgib posted 11-18-2009 01:34 PM ET (US)     Profile for Tohsgib  Send Email to Tohsgib     
PS...the mob usually does not want the body to disappear because it can't "send a message" if nobody knows he got whacked. Most hits are done in public or the corpse is left to be found so that the public or enemy knows what happened to "Billy no Shoes Nabrizzi" or "Sammy the shark Cabinelli", etc.
high sierra posted 11-18-2009 03:13 PM ET (US)     Profile for high sierra  Send Email to high sierra     
No, they don't float. They are still on the bottom of Tahoe. high sierra
ceshaw posted 11-19-2009 10:04 AM ET (US)     Profile for ceshaw  Send Email to ceshaw     
This is a pretty morbid topic!! Lol.
deepwater posted 11-19-2009 03:51 PM ET (US)     Profile for deepwater  Send Email to deepwater     
I thought the answer was to be for a not so smart 6th grader,, everyone assumed the barrel was full,,It wasent add to this the very warm water and the rolling agitation of the tides ,,Try shaking a can of hot gasoline and see how much pressure is produced,,the tank on your boat will expand quite a bit
fourdfish posted 11-19-2009 04:11 PM ET (US)     Profile for fourdfish  Send Email to fourdfish     
We have floaters come up in the Great Lakes all the time. Actually Crabby is fairly close with his explanation although his calculations may not be perfect. Anyway, it is indeed possible.
David Pendleton posted 11-19-2009 04:28 PM ET (US)     Profile for David Pendleton  Send Email to David Pendleton     
Didn't some guy just wash up in W. Michigan somewhere after being in the water for more than a year?
Searenity posted 11-19-2009 11:35 PM ET (US)     Profile for Searenity  Send Email to Searenity     
After reading this discussion, I'm to assume that prior to disposal of said body and drum the bad guys put a Boston Whaler logo on the side of the drum to send a message. One to the actions of the bad guy and one to the parent company of Boston Whaler, Brunswick, to warn them of their current business practices and where it would lead them. The "unsinkable legend" will be sleeping with da fish. Forgetaboutit...
Feejer posted 11-20-2009 07:29 AM ET (US)     Profile for Feejer  Send Email to Feejer     
Very interesting thread and it has me wondering about the whole floating can thing. So much so I'm going to try it with the neighbors cat. I'll need to use a smaller can though
BlueMax posted 11-20-2009 10:18 AM ET (US)     Profile for BlueMax  Send Email to BlueMax     
Feej - recommend a resealable 5 gallon bucket as proportionate. A well cleaned 5 gal metal roofing tar bucket may be apropos as compared to one made of plastic for your experiment.

deepwater tells me that banding the lid shut on 5 gal trash cans will work well for disposal too....
[Wait - was that just a Helpful Hunter's Hint... or a warning? hmmm, yeah, about that Big Bear Hunt with the Big Bear Traps and Big Hunting Dogs and all, what are we using for Big Bear Bait.....Gulp!? let's talk.... ^@^ ]

deepwater posted 11-20-2009 08:18 PM ET (US)     Profile for deepwater  Send Email to deepwater     
Baits all gone so we dont need the barrel ^@^
Tom Hemphill posted 11-25-2009 08:59 PM ET (US)     Profile for Tom Hemphill    
For what it's worth, I was browsing Henry Lee's Crime Scene Handbook (ISBN 0-12-440830-3 ) today. In that book he says, "As decomposition progresses the body will fill with gas and float..." My first-hand experiences support Dr. Lee's (somewhat broad) statement.
jimh posted 11-25-2009 10:00 PM ET (US)     Profile for jimh  Send Email to jimh     
When a 55-gallon drum is submerged, it displaces a specific volume of water. This never changes. Inside the drum there is a certain weight. This cannot change, as long as nothing enters or escapes the drum. If the drum weighed more than the volume of water it displaces, it sinks. It will stay sunk as long as the density of water does not change.

The weight of the drum cannot change unless some of the material inside the drum is removed. If gases develop and have enough pressure to escape, the weight inside the drum changes. If the drum becomes light enough, it floats. You must have material escaping from the drum for its weight to change.

MAFIA GUY posted 11-26-2009 07:01 AM ET (US)     Profile for MAFIA GUY  Send Email to MAFIA GUY     
Your supposition is correct. The drum must remain sealed. In practice we try to make the weight of the drum plus the corpse, and the extra weight added, at least 3 times the weight of the displacement of the water the drum will displace. This is a good rule of thumb, in order to keep the drum from rolling ashore during storms. We also like to dump the drums in deep water. In Miami, we use the Gulf Stream, and in NY we dump them in the Mud Hole off Long Island. We had a problem with drums rolling ashore in New Orleans during Katrina.


conch posted 11-26-2009 07:47 AM ET (US)     Profile for conch  Send Email to conch     
Here is another approximate rule of "drum",I have observed,a decomposing body will lift about a kilogram for each 30lbs of former live weight.An airtight container floats easier.The gases produced are not present when the container is originally sealed, though the bacteria and blowfly eggs are in the initial weight.

As an aside saltwater present in the left side of the heart will indicate whether the deceased drowned in fresh or saltwater no matter where you find the body.

Cheers Chuck

deepwater posted 11-26-2009 08:05 AM ET (US)     Profile for deepwater  Send Email to deepwater     
Its going to be a long winter,,What say Max ^#^

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.