NARRATOR: In the rural Pennsylvania countryside of 1832, Irish immigrants worked to build one of America's earliest railroads.

The men were constructing mile 59 of what would become the Philadelphia to Pittsburgh mainline at a site that became known as Duffy's Cut.

They left Ireland, a land ravaged by famine, disease, and violence, in hopes of a new life, but within weeks, they would all be dead, their bodies buried in an unmarked grave.

What happened to these men has remained a mystery for more than 180 years, their disappearance covered up by powerful forces.

Now a chance discovery by twin brothers Bill and Frank Watson has exposed this forgotten secret.

Our guys unfortunately walked out into a maelstrom, and they became cannon fodder of the industrial revolution.

Get out of here.

NARRATOR: It's a story that reveals a dark chapter in American history.

FRANK WATSON: It's important to tell this story, it's important to remember those who have given their lives to build up this country.

NARRATOR: The Watsons teamed up with other historians and scientists to uncover the truth behind the disappearance of these missing Irish railroad workers.

Yeah.

It looks like trauma.

Oh, my goodness.

[Shouting] NARRATOR: Using a combination of modern forensic science and old-fashioned detective work, they searched for the true story behind "Death on the Railroad."

In 1832, tens of thousands of young Irish men and women fled Ireland for the United States.

They went in search of the American Dream.

57 Irish laborers were among them, departing from the port of Derry in northwest Ireland for an 8-week journey across the Atlantic to Philadelphia.

Working on a railroad was the first step in their quest for a better life, but a silent killer stalked their tracks--cholera.

Just 6 weeks after their arrival, all 57 men were dead, and their untimely deaths became the stuff of ghost stories and legends.

[Whistle blowing] The discovery of a mysterious file detailed how the Irish immigrants were hired to work on one of America's earliest railroads.

It also revealed that when the men died the railroad went to great lengths to keep the men's deaths secret.

Just what happened to them was lost to history.

Twin brothers Frank and Bill Watson grew up with the railroad.

FRANK: My grandfather had told us stories of the railroad from when I was a little boy, from when my brother and I were kids.

We grew up with the railroad as part of our family story.

This is something we knew from the very nature of the file was not intended to get out into the public.

NARRATOR: After he died, they found this file hidden among their grandfather's papers.

It was never supposed to see the light of day.

FRANK: That actually comes in right on the first page, the first document.

"It is not desired to get it get out of the office."

We came upon a letter of George Dougherty, and in this letter, he says that his father told him that the bodies were buried where they were making the fill, and for us, that became the key.

NARRATOR: Determined to find out more, the brothers were joined by two fellow academics-- John Ahtes and Earl Schandelmeier.

They had two tasks-- verify the details in the file and find the location of Duffy's Cut.

Through their research, they discovered the railroad hired an Irish contractor Philip Duffy to build mile 59 of what would become the Philadelphia to Pittsburgh mainline.

No more water.

Get back to work!

Put your back into it, boys.

SCHANDELMEIER: Phil Duffy's a very interesting character.

He's a contractor, he's a businessman, he's an immigrant to the United States from Ireland, he's a good guy, he's bringing a lot of work to his fellow Irishmen.

At the same time, he's a villain.

Come on.

Time is money, man!

NARRATOR: Duffy's contract would be worth more than half a million dollars today, 3 times more expensive than any other mile of railroad.

AHTES: We found a very chilling official report, which said Duffy had been unfortunate because half his crew had died of cholera, not that they had be unfortunate but that Duffy had been because it slowed down the progress of his work and required the railroad to pay him more money.

NARRATOR: As they delved into the history of Duffy's Cut, questions about what happened to the workers piled up.

The file revealed that like so many other nameless immigrants the men were buried in a mass grave, but how did they die?

Was it cholera or something more sinister?

The team set out to find the location where the men worked.

Using old maps and modern technology, Earl Schandelmeier searched the countryside along mile 59.

SCHANDELMEIER: We had 3 aspects of the project that we were really focusing on.

The first was to find the area where they were living, the shanty area, second was to find the individual graves, and third was then to find the mass grave.

Now in order to do that, we needed to be able to figure out the topography of the landscape in 1832.

What we did was work from the archives, pull maps from the 1832, 1850, 1870 time period and interlay them with Google Earth maps of today.

In doing that and by also going out and walking the landscape, taking many thousands of pictures and video, we were able to take the landscape as it is and re-create the way it was in 1832.

Essentially, we've been able to take 7 or 8 acres or land and narrow it down to about a quarter of an acre, half of an acre.

So it gave us a finer area to search and sped up the process.

NARRATOR: But who were these men who met such a tragic fate?

Searching through the National Archives in Philadelphia, the Watson brothers uncovered the name of the ship the men boarded for America.

FRANK: The railroad file itself has this to say-- "The contractor in the early summer of 1832 "employed a large number of Irishmen who had but lately arrived on these shores."

And from January 1 to October 1, 1832, we find one ship coming directly from Ireland with a largely Irish passenger list of laborers, It's called the John Stamp.

We took the ship list and started doing a genealogical search on the names of the laborers, as well as other passengers.

We checked census records, death records, marriage records, and largely, the laborers on board the John Stamp disappear after they arrive in June of 1832.

Well, it's really important to remember the people who are listed on the ship list were real human beings.

One name that leaps out from this list is is John Ruddy.

He's 18.

Take care of yourself.

You'll do well in America, boy.

You'll do well.

Take care of yourself, son.

I will.

Do us proud.

NARRATOR: John Ruddy was from Donegal in the northwest of Ireland.

In the days of sailing ships, the crossing to could take up to 3 months.

Ruddy knew he would probably never return home.

FRANK: My brother and I--Bill-- we both have boys.

We could only imagine what it must have been like for their parents to say farewell to them when he came to America to be a laborer in a new land.

It's a very poignant thing for us to look at a name such and this and realize that he'd probably never see his family again.

NARRATOR: Like so many of the 400,000 Irish men and women who left for America in the decade after 1828, Ruddy had few options but to leave home.

MAN: In the 1830s, Ireland would have been a very divided and very conflicted country.

There was very few opportunities for a young man in Ireland at that time.

If you didn't have land at that period, probably the best thing would be to leave the country altogether.

There was very little civil jobs, government jobs.

What there were weren't open to Catholics, so if you didn't work the land of if you didn't work in any industrial outlet, which south of Ireland didn't really have-- northeast of Ireland did in Belfast and the linen industry and the shipping industry to a certain degree at that stage, but in southern Ireland or western Ireland, there was very little industry, and you start seeing patterns in the 1810s and 1820s of young men, particularly from the west of Ireland, away from the urban centers, leaving Ireland in droves.

What did you do back in Ireland?

I was a laborer, sir.

NARRATOR: When they arrived in Philadelphia, John Ruddy and the other Irish laborers were probably hired right off the docks by Philip Duffy.

They came to a country hostile toward Catholics.

With few avenues of employment open to the Irish, they were ripe for exploitation.

Duffy immediately took them out to rural Pennsylvania to build mile 59 of the railroad.

In early August 1832 after 6 weeks of backbreaking labor, cholera struck the camp.

MAN: Ruddy, get some water!

Give us that.

NARRATOR: Within days, all 57 men were dead, their remains buried in a mass grave in the dirt below the railroad tracks.

Using evidence they uncovered in the railroad file in the archives, the Watsons were determined to find out the exact spot where the men were buried.

FRAN, VOICE-OVER: The railroad believed that they were buried in this stone enclosure and had this built as a memorial to the men around 1909.

This was 1 of 3 theories, though.

There were two other theories in the railroad file.

The second theory is that they were buried in the area of their shanty, which is the bottom of the valley below us here, and the third theory is the railroad fill that was built in 1832-1833.

NARRATOR: The Duffy's Cut team scoured the valley in search of the mass grave the men were buried in.

They found evidence of the men's lives in the valley, but it got them no closer to uncovering their remains.

The breakthrough came when geophysicist Tim Bechtel joined the team.

BECHTEL, VOICE-OVER: I'm the rocks and dirt detective.

I'm the guy who can look at rocks and tell you whether they're fill or native material and where they might have come from, and I'm the geophysicist.

I have the equipment that can see into the ground and tell us where things are that we might want to expose.

NARRATOR: The landscape has changed dramatically in the nearly 200 years since the railroad was built.

Would it even be possible for Bechtel to find the gravesite?

The area where they worked stretches over half an acre, a huge expanse.

In hopes of narrowing down possibilities, the team referred to a letter written by James Dougherty, whose father was a railroad worker during the same period.

FRANK: What's interesting in this letter is that he was asked where the men were likely buried by his supervisor, and this letter says this-- "I know that they do not know where the bodies were buried, "but I heard my father say they were buried where they were making this fill."

And making the fill seems to be the key phrase.

What does that mean?

Could mean generating the fill material, the fill meaning the dirt that goes in here, or the fill could mean the embankment itself, and as we stood here and talked about it and thought about where someone would be able to see the bodies-- or the burial, we realized that making the fill had to mean they're in the embankment, so we realized that this is where we needed to focus all of our efforts, on this fill embankment, where they made the fill.

NARRATOR: With ground-penetrating radar, Bechtel could see the inside of the hill.

The team expected to find a large anomaly signifying a mass grave, but instead they discovered something far different, a number of smaller anomalies.

So it's quite possible that instead of one grave with all 57 bodies in it, it's quite possible that there may be several smaller graves.

NARRATOR: To confirm his suspicions, Bechtel needed more detailed information about the subsurface.

Placing a series of probes into grid patterns on the hillside, he sent electrical pulses through the soil.

These pulses travel differently depending on what they pass through.

BECHTEL: Where there's just damp soil, the current will flow very easily.

If there are air spaces or large rocks, the current doesn't flow as well.

NARRATOR: Using the data collected from the electrical pulses, Bechtel created a map of the subsurface of the embankment.

Now he could look into the heart of the fill dirt and tell the team exactly where they should be searching for remains.

BECHTEL: What we're looking at are depth slices through the hillside.

So each picture represents a progressively greater depth below the ground surface.

NARRATOR: Combining these images, Bechtel could see anomalies below the surface.

NARRATOR: The early 1830s marked the beginning of a century of industrial growth in the U.S. America was changing beyond all recognition, and the changes were spurred by a revolution in transportation.

MAN: The building of turnpikes and canals and then of course in the late 1820s and early 1830s the first railroads.

Railroads are gonna play an immensely important role in the first half of the 19th Century, especially in the Northeast and Midwest in terms of beginning to integrate an American economy.

The 1830s in the United States is really in the midst of an enormous period of change and tension in social and economic life, in political life, in cultural life, as well.

Certainly one of the largest areas of change has to do with the tremendous economic expansion that's taking place in many parts of the country.

NARRATOR: These massive building projects called for huge amounts of cheap labor working in appalling conditions, and in the 1830s, only one immigrant group was willing to do such work-- the Irish.

MAN: Irish immigrants quickly became the preferred labor source for the building of American railroads.

They could be hired very cheaply, they could be fired on a whim.

A lot of employers believed you could work them virtually to death and no one would care, that they were disposable, and so for those reasons and the fact that the Irish immigrants also were often very desperate for work and were the only ones willing to take work in these kinds of conditions, and Americans were very happy to rely on the Irish more than any other group to do the manual, unskilled labor to build the railroads, the laying of the tracks, the building of the road bed, the hauling of the materials.

That was all work that the Irish very quickly came to dominate.

[Indistinct chatter] NARRATOR: The team spent more than 6 years searching for the Irishmen's remains.

By 2009, armed with Bechtel's research, they knew exactly where to dig.

For once, "X"really did mark the spot.

And so we had to sort of plow through or blast through with pickaxes through fill to to get to the spot where this set of remains was located.

It's about 3, 3 1/2 feet in, about down to here, and we started out with a tibia and moved through the body until we got to head pieces about in here, several fragments of a cranium.

And we've got by the end of that first day on March 20 pretty much an entire man.

NARRATOR: John, Earl, and the brothers decided to postpone the dig until the summer.

They believed they had located the site, but before a large-scale excavation could begin, they wanted to consult more scientists.

They brought in physical anthropologist Dr. Janet Monge.

Her role would be to identify the ethnicity of the remains and to find out what exactly happened to these men.

MONGE, VOICE-OVER: For me, the intriguing part was the story that surrounded Duffy's Cut.

The fact that the possibility exists that they could derive 50-plus skeletons from a single kind of mass grave situation, what that would actually tell us and show us and elucidate essentially that part of American history is just fascinating to me personally.

Archaeology would now play a key role.

The team needed someone with experience excavating mass burial sites.

One of Monge's students Sam Cox had worked on archaeological digs in Africa and Europe.

With Monge working the lab, Cox's role would be to supervise the dig.

COX: For a couple reasons, it's important to have physical anthropologists out here.

First one really to be able to identify bones, secondly is to be able to look at how the bones are laying out to interpret the way the remains are in the ground and then to help sort individuals.

NARRATOR: The team hoped to uncover the mass grave at last.

Using Tim Bechtel's radar map, she laid out a grid that would be their central focus.

Almost immediately, they uncovered another set of remains.

I think this is a bone right here, Sam.

Which one?

Right here.

Yep.

Careful.

Oh, my God.

It is.

Look at that.

Is that--is that a pelvis?

Is that the iliac crest?

We'll have to look at it.

Holy cow!

Look at that!

The skull will probably be somewhere right down in here, right?

Hopefully.

That's what our hope is, right?

Right under that.

It's a very sad thing seeing the remains of a human being just buried here and having these roots rip them apart, but there's a sense of relief, too, that his story's going to be uncovered as his moral remains are uncovered, and it's just an amazing-- an amazing feeling, an amazing feeling, both sadness and joy at the same time.

You know, just-- it kind of rips your heart out.

I mean, I think we would all say it kind of rips your heart out seeing these bones like this, but nonetheless, very exciting, very exciting.

COX: So that one be careful because it's really close to the bone.

You be careful of your thumb.

COX, VOICE-OVER: The next step after the roots come out is we're gonna clean everything up so that we can see exactly what we're looking at.

We want to see how they're in the ground.

We want to find out how this person was laid down.

So we want to see what the whole skeleton looks like together.

Good job.

Thank you.

NARRATOR: The team believed the remains they'd found were part of a larger mass grave...

Right.

Very fragile.

but as they continued to exhume the bones, they made a surprising discovery.

COX: So what we just started excavating here is an individual who's laid out going in this direction.

We have his upper arm here, we have scapula-- so his shoulder-- some ribs, and some vertebrae going down this way, and then cranium up here.

The head is in the west, the feet pointing toward the east, which is very typical Christian kind of burial.

Most interesting thing that we found about this particular skeleton is that we have a nice, dark wood stain that's running up around the body in rectangle.

You can see it coming down in a corner here, which would indicate the remains of a coffin.

NARRATOR: Nobody was expecting to find a coffin at Duffy's Cot.

The team thought they were digging through the gravesite of cholera victims.

Cholera was a highly infectious disease.

Its victims were often buried quickly and with little ceremony.

Why were these bodies in coffins?

Professor Kingston Mills from the immunology lab at Trinity College Dublin studies the effects of the disease.

Cholera is an infectious disease that's caused by the bacteria Vibrio cholerae, which is taken in by the oral route, so people would get infected by coming in contact and drinking contaminated water and contaminated food that have the bacteria on it, and then the bacteria start multiplying in their intestine, their gut, and this causes severe gastrointestinal pain and diarrhea.

The patient loses a lot of water, so they become dehydrated, and a lot of them will die.

In the 1830s, there wouldn't have been antibiotics, so there was no real way of treating it, and the death usually occurred within a few hours, up to 24 hours from severe dehydration.

Roughly 50% of those that would have contracted would have died, but a significant number would have survived, so it's highly unlikely that 100% of any group will die from this disease.

[Coughing] NARRATOR: The Watson brothers' file reported all 57 men died of cholera, but a report from anthropologist Janet Monge had them wondering if something or someone else was responsible for the deaths.

I see them.

I probably could have... MONGE, VOICE-OVER: Basically I do think that appears to be a blunt force trauma on the skull, OK, which to mea looks like it's unhealed, OK?

So it's this one that I have my suspicions about, and it's this one that we'll spend a great deal of time analyzing just see if we can see any kind of healing associated with it, something like that, which would give us an indication of whether or not it was really something sustained at the time of death.

NARRATOR: The evidence Monge discovered, that the body suffered an injury at the time of death, raised troubling questions.

He had two skull fractures prior to his death that may actually have been roughly contemporary with death, possibly the cause of his death.

There's a possibility here that this man was murdered.

NARRATOR: Monge believed the bones belong to a young man no more than 20 years old.

This skeleton may be the remains of John Ruddy, the young man from Donegal who left Ireland with hopes of a new life in America.

BILL: We can put a name to this man that is, in terms of the fulfillment of the quest, this is what we're doing.

We're trying to get these guys out of this anonymous grave.

I mean, these hard-hearted guys back in the 1830s didn't care whether they lived or died.

They were forgotten, their family members in Ireland never heard from them again, and there's a sense of justice now.

We know who this guy is.

NARRATOR: After discovering that the first body excavated suffered a head wound before death, the team was desperate to find more bodies at the site.

Did all these men die of cholera, or were some of them murdered?

Evidence of trauma on other bodies might explain why not a single man who worked at Duffy's Cut survived.

COX: Today we're basically expanding our trench, and we're trying to see if we can find any more graves, so we're digging out towards this big tree to see-- because we have a theory that some of the graves might actually be underneath it, so we're kind of exploring at the moment to see if we find anything.

Hopefully we can get this dug out...

I'm hoping in about an hour.

There's bones!

You can see a little line.

It goes all the way back.

All right.

Got to get that clear.

Ohh!

What?

Casket.

Casket.

Wow!

Very well preserved pieces of wood in here.

We know that once we smell this particular odor that we're very close to a body.

This is the smell of death.

There's no doubt about it.

NARRATOR: The team found two more bodies buried in coffins in the embankment.

This discovery, along with the evidence of possible head trauma on John Ruddy's skull, raised more questions than answers.

Was this a simple case of cholera, or was it the site of mass murder?

The story of what truly happened at Duffy's Cut still eluded them.

AHTES, VOICE-OVER: I think logic would tell us that the bodies that are buried lowest in the fill were the ones that were placed their first, so these are probably the first men who died at Duffy's Cut.

The question of whether these are men who died of violence from the neighborhood or work accidents or of cholera or combinations of all 3 is something that we're going to have to piece together now.

NARRATOR: While the team excavated the remains of a third body, Sam Cox took the bones from the second skeleton to Janet Monge for cleaning and analysis in her University of Pennsylvania lab.

Oh!

That's nice.

Ohh!

Uh-oh!

Mm-mm-mm-mm.

Mm-mm-mm-mm-mm.

Let's get all the roots off his head.

MONGE: It's a muscular man, and it is with all the classic male features, so it's easy to really say with a great degree of assurance that this is a male.

This is just a dandy.

Ooh!

What's this?

Yeah, it is.

It's very open.

Yeah.

There's something up with this.

Yeah.

Something's up.

This might be a nice blunt force trauma.

This damage appears to be damage that occurred around the time of death.

This is plastic deformation, so you have the blow.

This is a piece of dislodged bone that if this individual was alive and had brain tissue, it would have jettisoned a piece of bone right into the meninges and into the brain.

I mean, I don't know all the details of all of the evidence associated with Duffy's Cut, but it is possible, given the fact that we've got that other one and this wound like this, both of which I'm leaning towards perimortem on, that they weren't hit in some way, maybe killed.

BILL, VOICE-OVER: Duffy's Cut has yielded some very interesting secrets this week.

We did not expect to find evidence of violence at the very beginning of this dig, we did not expect to find coffins, but every day, something new, something surprising, and I think that these guys wanted us to find them, and this is a case where a bunch of individuals are screaming out for justice across the centuries.

NARRATOR: During this period of the dig, the team discovered the remains of 3 bodies but were no closer to finding the mass grave.

Geophysicist Tim Bechtel returned to the site in order to expand his map of the embankment.

Starting in the summer of 2009, we had electrical imaging data that went down to about the big tree, and it was in that that we had found an underground very resistive area that was in the hillside above where the blue tarp is now, and right on the edge of that zone is where we found the first burial that we're calling John Ruddy.

We thought that might be the mass grave.

As it turned out, we found that the first remains were in coffins, so clearly we didn't have the mass grave right here.

So we went back in August of 2009 and extended the grid to get an idea of how extensive this resistive anomaly might be, and it turns out it runs the whole way down the slope under the big tree and on past the little one.

Really my data ends at that little tree, so I suspect that we'll continue to find them on beyond the limits of where I have data.

NARRATOR: A year later, still so much of the story of these men's lives remained hidden.

In the summer of 2010, the team returned to the site.

Sadly, they were missing John Ahtes, a founding member of the team who passed away suddenly just weeks before the dig started up again.

He was only 48.

His loss was keenly felt by everyone on the project.

BILL: Duffy's Cut and John were synonymous, and we lost a big part of the heart of this team.

I mean, we can all say that.

Close to John for decades.

It goes before Duffy's Cut, but we lost part of the heart but not the soul because he's with the 57 men now, and help direct us to see this through.

He hasn't gone anywhere, though.

He's guiding us, there's no doubt about it.

Yeah, we feel he's still--he's still behind us, that's for sure.

He knows more than we do now.

He's laughing at us probably.

He always thought he knew more than we did.

For 8 years, it was like the 4 Musketeers.

For 8 years, we've been-- as Earl said, we've been the 4 Musketeers for 8 years, and now it's down to the 3 Musketeers.

NARRATOR: John's passing made the team even more determined to get to the bottom of the mystery.

With Bechtel's additional research, they soon found another skeleton.

MONGE: Yeah.

I think it's going that way.

Should be going kind of this way, east-west.

Could it be?

OK.

It could be, but it's definitely not going this way.

Could this be another body?

Could there be two bodies here?

COX: It's possible.

I mean, we have a couple of burials in here, so we could have a couple people.

MONGE: We may be looking at the first of the group of people who died.

Maybe they were sick with cholera.

We've seen this in other archaeological cases.

Somebody's sick with an infectious disease, in a lot of pain, and mercy killing takes the form of being bludgeoned to death.

So they're looking at now 4 graves, OK, which contain 4 more of these individuals, which is likely to really allow us to refine our picture of what we think happened in those final days at Duffy's Cut.

NARRATOR: But why were the events at Duffy's Cut kept such a secret?

Cholera outbreaks were well-reported in local and national newspapers in those days.

Why is there no public record of the outbreak at mile 59?

Did the railroad have something to hide?

The team hunted through the Chester County archives in search of an answer.

Wow.

It only says that 8 people died at Duffy's Cut.

8?

So-- 8.

It's right here.

This is the November 7 "Village Record."

Wow.

"8 of which proved to be fatal.

It then ceased suddenly as it commenced."

And internally they were saying that a number as high as 60 died.

They knew that his 57 men died here, but they're reporting to the newspaper that there's only 8 men who died.

This is railroad spin then.

This is railroad spin is right.

Classic.

That was from the November 7 "Village Record"article, so they say here that there were only 8 men who died rather than the 57 that Martin Clement has in the official Pennsylvania Railroad account of this incident, so for us, it's just a strange part of this mystery.

Why did they downplay it?

BILL: And also this is a very secretive thing from the beginning.

There's a spin going on from the very, very start of this event, and it is out of proportion to a natural disaster.

NARRATOR: Murder, as the evidence suggested, would certainly give the railroad reason to cover it up.

They may have feared retaliation by Irish rail workers for the death of their fellow countrymen.

ANBINDER: I think any time that you had violence against Irish immigrants in early American history you typically had a response in kind from the Irish immigrant community, so all of early 19th Century American history is full of episodes in which native-born Americans will protest against Irish immigrants, sometimes violently, and usually the Irish responded.

Get out of here.

Get out of here.

Nobody's stealing our jobs.

ANBINDER: So Irish immigrants typically did not take violent discrimination against them lying down.

They tended to respond in kind, and that was part of the way in which the Irish immigrants were viewed.

Come on, Ruddy.

NARRATOR: Back on the site, the team had almost completely excavated the fourth skeleton when they uncovered another set of remains.

BILL: Well, it looks like we've got another skull here, and he looks like he's west to east just as many of these bodies have been.

COX: So we've been basically clearing out all the soil on top of the graves that we found earlier, so it looks like what they're doing is cutting into the hill to bury graves so that the coffins are being laid in flat, even though we're on a slope.

Sam Cox's discovery led Earl Schandelmeier to explore how the bodies may have been interred.

He believed he had discovered how the men were buried by their colleagues.

SCHANDELMEIER: As you can see in about a minute and a half, I can etch out the fill that's here on this hillside, giving myself a nice, flat area.

Here's about 6 1/2-foot long, 2 1/2 feet wide, and it's deep enough that if I actually took-- we'll use this... [Grunts] piece of wood as an example, and we bring one load of dirt on top, and you can see within two loads of dirt, this whole entire coffin is gonna be gone, and we're not going to have to extend the fill much further than we would have originally.

NARRATOR: Another set of remains, the fourth, was ready to be exhumed.

Measuring nearly 6 feet in height, the man was incredibly tall for the era.

To his fellow Irishmen, he would have been a giant.

What do you find on that?

NARRATOR: As they removed the bones, they saw something shocking.

Wow!

Look at that.

After 177 years, this poor guy's gonna leave Duffy's Cut.

Ooh!

What's that?

Oh, my goodness!

Oh, my!

Much like a bullet hole.

Is that bullet hole?

It might be.

Oh, my goodness!

Look at how round that is, Sam.

What do you make of that?

I don't know.

Wow!

SCHANDELMEIER: Sam, is that real clear?

I mean, is that very clearly trauma?

That's not-- It's definitely a trauma.

Yeah.

This looks like the trauma here, and then we've got a second one.

It looks like we've got a mass murder scene here.

FRANK: Yes, yes.

This poor guy.

They killed these guys.

They did.

This is the reason for the cover-up.

It's why they had to keep it secret for a hundred-and-some years.

FRANK: It's exciting to know the truth.

Just think about it.

His parents never knew this happened to him.

They never knew that he was left here in the middle of nowhere in Pennsylvania.

The only people who knew were the railroad.

Yeah.

NARRATOR: The story of Duffy's Cut has taken a dark and sinister turn.

The evidence shows that these Irishmen came to a grim and grisly end.

Of the 5 sets of remains, one skull was so badly decomposed it was impossible to say how the person died, but 3 of the skulls showed evidence of trauma at the time of death.

What story did the fifth skeleton reveal?

MONGE: Sam, can you come here?

Yeah.

What's up?

Well, you want to know what, fellas?

I don't know whether or not I should tell you this now, but we have Duffy's Cut chick.

You think so?

We got a chick.

Yeah, but I think what's really kind of giving me this clue at the moment is this really, really, really small palate.

Look at the size of that second molar.

It's a very small head.

That's teeny, OK?

I can't really see this as being anything but a female.

But what does it mean for us if we do have a lady out there?

I mean, how do we-- how do we reconcile that?

Well, I mean, as I've always said, it doesn't really do anything to the story because the story is really just unfolding.

It now just has to encompass a female within its structure.

Yes.

I don't need any women.

NARRATOR: Two women traveled with the laborers on the John Stamp.

Thanks to Monge's research, the team knew that the female skeleton was about 30 years old at the time of death.

The ship's passenger list provided a clue about who this woman was.

One of the women was a 29-year-old widow named Catherine Burns.

She was from County Tyrone.

She traveled with a John Burns, who looks like her father-in-law.

Catherine and John Burns both disappear after they come to America.

Sir, sir, sir.

Please, sir.

I don't need any women.

Some of these boys need someone to look after them, sir.

Please, sir.

BILL: Our thinking is these railroad work sites would have needed someone to wash the clothes, cook the food, and it would not have been out of the norm for one of these workers to have brought the woman with him to the site of mile 59.

Certainly from our perspective, finding a woman buried with railroad laborers was a shock.

It just--it gave a totally different picture in my mind to know that they murdered a woman, as well as the men.

Further explains the cover-up.

NARRATOR: Back in the lab, Monge confirmed Cox's suspicion that the tall Irishman met a violent and bloody end.

There are definitely two different wounds on the skull.

We've got this one on the top, and then we've also got on--it's his right side-- a big kind of-- a gash or triangular-shaped cut, which is a second trauma.

Kind of really now curious about it.

This is really, really thick.

This has been clunked.

You don't think it's a bullet?

Yeah, I do think it's a bullet.

Oh, OK.

I mean, this is unusual.

The edges are jagged.

There's something odd.

I mean, it certainly has all of the characteristics of almost like an ax wound.

I mean, this is a very interesting skull.

NARRATOR: Monge sent the skull to be scanned at the university hospital, and the results pointed to violence.

MONGE: When the CT scans came back to the lab, we were able to, I think, pretty convincingly confirm that we were looking at a bullet hole, that it was produced by a lead bullet.

Let me point to the evidence for you.

These flakes and this object, OK, by the red arrow pointing at it are actually unusual objects within the construction of the overall density of the bone.

We suspect that that's lead swipe, but very interestingly, lying in a compartment completely sealed at the back of the skull is another one of these very dense pieces of material, which we suspect is a bullet fragment.

This is pretty convincing in showing us the evidence that this individual was perhaps struck in the head with an ax, shot in the head probably pretty close to the same timeframe.

We're not sure which one occurred first but certainly would have guaranteed the death of this individual.

NARRATOR: In 1832, Irish Catholics coming to America would have been looked up with suspicion and distrust because of their religion.

Could that be why the railroad workers were murdered?

AHTES: Westchester, Chester County generally would not have been a place terribly welcoming to immigrant labor in 1832, particularly Irish Catholic laborers.

It was a place where the social and economic order very much reflected the hierarchy of the colonial period, and the changes wrought by industrialization were painful and resisted out here.

NARRATOR: With the evidence mounting, the Duffy's Cut team believe they may have found those responsible for the killings.

And what we've got out here specifically in Chester County there are groups of individuals who fear and revile the immigrant.

We've got examples of cross-cultural violence reported in the paper... CATHERINE: Aah!

and we have groups like the East Whiteland Horse Company operating as a vigilante organization very close to the site of this work, who were the law in the absence of a constable, and the individual who owned mile 59, his family ran the horse company.

NARRATOR: As cholera began to strike the railroad workers, could the vigilantes in the horse company have moved to protect their community from the disease by attacking the Irish in their midst?

By 2011, the team had removed 6 sets of remains and found coffin stains for two more burials, though the skeletons had been washed away.

They scoured what is left of the 1832 railroad embankment but found no more bodies.

So where are the remaining 49 Irish laborers?

For the answer, Bechtel must go back to the 1870s, when the railroad company set about improving the line.

BECHTEL: When they were straightening the railroad and building a new embankment, they would have needed material, and the 1832 abandoned embankment would be very easy material to dig, so we think that they were digging that material out and reusing it, and in the process of doing that, they probably hit the mass grave, and that freaked them out.

They probably at that point disinterred the bones that they encountered, and maybe they brought them up here, where they were filling in the 1870s and buried them here, and then put a memorial wall over them.

Screen clear?

WOMAN: Yep.

OK.

Here we go.

Check and make sure the sampling thing flashes.

NARRATOR: To prove his theory that the mass grave is under the memorial wall, Bechtel placed a series of listening devices known as geophones connected to a sound reader in a semicircle around the memorial.

Using a jackhammer, he sent sound waves through the earth, measuring how fast the sounds traveled to the geophones.

If something, like a body, is buried in the ground, the sound waves will travel more slowly through that area.

BECHTEL: So it's our way of kind of hunting this whole plateau area to try and find where the mass grave might be if it's up here near the wall.

Which one looks to you like the slowest arrival?

7.

7.

Definitely.

Yep.

See how these are right behind 40?

These two drop off, that's slow, and then they pick up again over this direction.

You're on the shot point?

Yeah.

OK.

I'm on channel 7.

This was the slow one, so somewhere between me and you is the low velocity zone.

NARRATOR: This anomaly runs through the ground where the memorial lies.

It's not this exact location, but it's sort of centered here.

It's a zone somewhere within in this quadrant of the wall where the material at depth is lower velocity.

So, Tim, this could be the spot here as you're saying, and if so, then Clement's 1909 stone wall and then the original 1870 wooden fence may indeed mark the spot of the mass ossuary.

Yeah.

They certainly could.

They could have been in the right place.

The mass grave may have originally been in the valley, but in the 1870s, they may have hid it and reinterred them up here and put the maker right on top of them.

Wow!

So many generations of railroaders were correct it looks like.

We always thought that we would find the mass grave and the individual burials were gonna be impossible... Yeah.

It's exactly backwards.

and then this thing's waiting here?

Even if we can't dig to retrieve these remains, we can at least properly note and mark and remember this place as the burial place of the rest of the men, the ossuary.

Yeah.

We're awfully close to the active railroad, so that would represent a safety and an engineering hazard.

I don't think it's possible to recover these fellows.

It's a little frustrating that we can't get to them, having recovered the others, but I'm OK with that because we know what kind of life they led, and we know what kind of death they had, and there's some comfort in knowing at least where these guys are, even if we can't get to them.

Tisn't looking good, lads.

That's 10 now, and he's not far away either.

NARRATOR: The Watsons' railroad file showed that some of the men tried to escape the valley at the start of the cholera epidemic.

Let's go!

Let's go!

The team believe that these remains belong to those men.

BILL: Our thinking is that the vigilantes rounded our men up after having escaped the valley.

We've come to the conclusion uniformly among the historical part of this team that those individuals were coffined as they were to prevent those men in the valley from seeing the bloody mess that was inside.

NARRATOR: The sealed coffins were dumped back into Duffy's Cut by the vigilantes.

The surviving Irish railroad workers buried their comrades, never knowing what had happened to them.

After the remaining men died, Duffy had their bodies interred in a hidden mass grave.

Philip Duffy, the railroad company, and those who murdered the Irishmen chose to forget about their crimes.

The railroad contract made Duffy a wealthy man.

The Philadelphia to Pittsburgh mainline was an enormous success, and it led to the creation of the Pennsylvania Railroad, which by the middle of the 20th Century was one of the largest companies in the world.

The story of the men at Duffy's Cut was kept alive by subsequent generations of Irish railroad workers, who hoped their countrymen would one day receive a proper burial.

[Bagpipes playing] In March 2012, the remains were finally laid to rest at West Laurel Hill Cemetery outside Philadelphia.

FRANK: Certainly this is just one part of the telling of the building of our country here in the United States.

It's an important part of the picture, but 57 names, 57 individuals will be remembered for future generations As many as 50,000 individuals died building the railroad from east to west, and at least 57 of them will be remembered.

NARRATOR: The team has one final duty to perform.

The remains of the young man they believe to be John Ruddy are brought back to Ireland for burial in his native Donegal.

More than 180 years after he left these shores, one of the men of Duffy's Cut is coming home.

FRANK: For me, the most amazing part of this is that this was the first man we recovered from Duffy's Cut, and he's the only man to be buried back in his homeland, so it's a very fitting end to an 11-year pilgrimage for us.

It's an amazing thing to be able to go from a file to a grave.

And it's very poignant obviously for us as fathers.

You know, we got sons about the same age as this guy, and how horrible it must have been for his parents to see that ship go away and never hear from him again.

Now he gets back to his home turf here, it's absolutely incredibly meaningful to us.

SCHANDELMEIER: Bringing it back here was the most amazing thing I've ever down.

To set here, to be on Irish soil, there's nothing more important.

I could have never done anything more important in my life ever, and the feeling of just pure joy and bliss putting him in the ground, I can't explain it.

AHTES: The immigration myth, if we can call it, as part of American history is one that generally suggests that all was well once people arrived in the United States, and so the darker side of that immigrant experience is an important part of our collective memory and something which we really need to explore more deeply.

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