Stories in Stone (7 page)

Campbell stood just below the site of Willard’s ledge, or what was left of it, since any rock that enticed Willard is now
twelve miles away in the monument.
A ledgy granite hill covered, probably as it was in 1825, by pine trees and boulders, rose
above the mostly flat and bare ground.
As Campbell walked among piles of cut and uncut granite, he pointed out where the masons
squared and numbered stones, the blacksmith’s shop, and the superintendent’s building.

He stopped near several large rectangular stones partially buried in the soil.
“This is mile zero of the Granite Railway,”
said Campbell.
About 125 feet of moss-covered path ran along the ground.
Every eight feet a ten-inch-square, seven-foot-long
granite block, known as a sleeper, lay perpendicular to the path.
This is the only relatively intact section left of the Granite
Railway, although no rails remain.

The sleepers rest on several feet of crushed rock, which Bryant used to protect the tracks from frost-induced buckling.
He
then placed pine rails, six inches wide by twelve inches high, on top of the sleepers.
The tracks were five feet apart and
held in place by iron pins, several of which still stick out of the granite.
On top of the pine ran four-by-four-inch oak
timbers supporting a quarter-inch-thick iron strip, called a strap rail, where the flanged wheels rested.
When the wood wore
out, Bryant replaced it with granite.
As we reached the end of the path, which extended into a shrub-filled swamp between
rock walls, Campbell’s enthusiastic gestures nearly propelled him off the raised railroad, but I grabbed him before he tumbled
off the six-foot-high wall.

Bryant’s most innovative design was his rail car, fourteen feet long, eleven feet tall, and supported by six-and-one-half-foot-high
wheels.
The empty car would back up to where the cut blocks were.
Workers would turn gears on the car, which would lower a
pallet supported by six chains.
They would unhook the pallet, move the car forward, load a block or blocks, and back the car
up again.
“One man could raise a six-ton block, which could be up to three feet wide and thirty-two inches high,” said Campbell.

After crossing on trestles over the swamp, the railroad curved around Pine Hill and by Willard’s house, before heading straight
northwest to the Neponset River.
Along the way it dropped eighty-five feet.
Two pullouts allowed cars going in opposite directions
to pass.
Not that traffic was much of a problem but the route did cross several streets, where chains prevented slow speed
collisions.
The railroad ended at a twelve-hundred-foot-long wharf, which took six months to build and cost two-thirds of
the total fifty-thousand-dollar price of the railroad.

Barges and sloops carried the blocks down the Neponset, across Boston Harbor to Charlestown.
They landed at Deven’s Wharf,
coincidentally near where Paul Revere began the most famous horse ride in American history.
Subsequent filling in of the harbor
has obliterated the wharf, which was adjacent to the Charles River Bridge.
Ox-drawn carts carried the blocks the final few
hundred yards up to the building site.

Bryant made the first test run of the railroad on October 7, 1826.
Workers loaded three cars with sixteen tons of rock and
a single horse pulled the entire load.
The horse arrived at the Neponset wharf in less than an hour.
The railroad men celebrated,
drinking from brown glass bottles imprinted with “Success to the Railroad.”
²¹
The next load would not arrive at the river until the following spring.

“Willard was never a big supporter of the railroad.
He wanted the work done faster,” said Campbell.
Willard also worried about
stone breakage on the railroad and paid for a survey of the twelve-mile overland route.
“He started work on quarrying in March
1826, built up a huge collection of blocks, and had to wait until March 1827 before the railroad carried any stone.
He stormed
off the job several times in the first few years because of his concerns,” said Campbell.

“The Quincy Granite is its own special case,” said Dick Bailey, a geologist at Northeastern University.
²²
He has spent more than three decades studying New England geology, focusing primarily on the Avalon terrane, a suite of rocks
central to understanding the oddball history of the Quincy Granite.

A terrane is a fault-bounded body of rock, with limited extent, characterized by a geologic history different from the history
of nearby rocks.
Current thinking holds that the Avalon terrane began life as part of South America.
The central line of evidence
comes from chemical analysis of minute minerals, called zircons, found in both northwest South America and in rocks around
Boston.
Bailey rejects this model.
He favors an African origin.

His main evidence is a truly astounding creature, a trilobite fossil discovered in 1834 at a slate quarry three miles east
of the Granite Railway Quarry.
The most charismatic crustacean of the Cambrian Period, trilobites foraged on ocean bottoms
for 300 million years.
Most species were a couple of inches long, or shorter, and resembled a pill bug, or rolypoly.
The one
from Quincy,
Paradoxides harlani
, was twelve inches long, which led Percy Raymond, a curator at Harvard’s Museum of Comparative Zoology, to write in 1914
that
Paradoxides
is “such an oasis in the sterility of Massachusetts paleontology” that it borders on the “domain of romance.”
²³

Raymond didn’t know the most exotic part of the story, that the 510-million-year-old
Paradoxides
was not a North American trilobite.
Its closest relatives, including a sixteen-inch-long Moroccan giant, lived in north Africa.
Along with several other much smaller trilobites from the same quarry, the Quincy fossils provided the first clue that Avalon
was an exotic landmass.
“I am a paleontologist, which is why I haven’t given up on the northwest Africa position.
There’s
something a lot more compelling to the trilobites than to isotope analyses,” said Bailey.

Avalon’s plate tectonics history can best be described in accordionlike terms with continents opening, oceans closing, oceans
opening, and finally landmasses colliding.
The terrane’s story began between 700 and 800 million years ago on the edge of
a supercontinent known as Rodinia (Russian for motherland).
Consisting of parts of Gondwana and Laurentia (North America and
Greenland) that had glommed together 300 million years earlier, Rodinia was beginning to rip itself apart.
A massive rift
valley formed and filled with nearly pure quartz sands carried by rivers.
Known as the Westboro Formation, the sands later
lithified into what is New England’s oldest sedimentary rock.

The next oldest rocks formed 620 million years ago when a closing ocean basin slammed a narrow belt of islands into the continent.
This collision produced a pink granite that resembles Ben and Jerry’s Cherry Garcia ice cream.
Known as the Dedham Granite,
it is geologically the oldest Boston-based rock used as building stone.
Dedham Granite is also what the Pilgrims first stepped
onto when they landed in 1620.

As another rift opened, sediments began to flow into a marine basin.
This collection of rocks has been designated by geologists
as the Boston Bay Group.
Bailey’s work has helped show that more than seventeen thousand feet of mudstones, sandstones, and
conglomerates accumulated in the sea that dominated the area between 605 and 543 million years ago.

The Boston Bay Group includes two other important local building stones.
The first is Cambridge slate, one of the earlier
stones in the building trade.
The second building stone is a purple-hued stew of boulders, cobbles, and pebbles suspended
in a fine-grained mud.
Used in over thirty-five Boston churches and known as Roxbury puddingstone, it was celebrated by Oliver
Wendell Holmes in his 1830 poem, “The Dorchester Giant.”
²⁴
He attributed the odd stone composition to the giant’s three unruly children and a “pudding stuffed with plums.”

They flung it over to Roxbury hills,

They flung it over the plain,

And all over Milton and Dorchester too

Great lumps of pudding the giants threw;

They tumbled as thick as rain.
²⁵

After the children finished their roughhousing, Percy Raymond’s great trilobite appeared, roughly a half billion years ago.
The foot-long crustaceans crawled around the shallow water of the Iapetus Ocean (Atlas’s father in Greek mythology), off the
edge of the small Avalonian landmass.
This microcontinent, akin to modern-day Madagascar, lay just west of Gondwana, far south
in the southern hemisphere.
And then Avalon, and its cache of trilobites, abandoned its point of origin near Africa and began
to travel north on the plate tectonics highway.

Around 450 million years ago, Avalon passed over a hot spot, or zone of weakness in the earth’s crust where heat escapes from
the mantle, as now occurs in Hawaii and Yellowstone.
This fiery Bunsen burner melted surrounding rock and generated a hot,
dry alkali-feldspar-rich magma that punched its way into a trilobite-rich sedimentary rock.
The Quincy Granite was born, although
no one knows exactly where or when, noted Bailey.

Avalon continued to glide north and west through the Iapetus, probably jostling with other terranes before docking on the
eastern edge of North America sometime between 425 million and 370 million years ago.
Another terrane rammed Avalon between
300 and 250 million years ago, followed closely by Africa and Europe.
This was the final squeeze of the accordion and marked
the penultimate stages of the closing of the trilobite-rich Iapetus Ocean and formation of Pangaea.
The assembly of North
America, at least in the east, was more or less over.
Geologic quiet has dominated the east ever since, with a few big events,
most notably the breakup of Pangaea, which started the continents on their journey to their modern locations.

Because of this geologic calm, the Quincy Granite did not get beaten up.
By not experiencing the trauma of continental collisions,
great uplift, and weathering, or deep burial under later sediments, the Quincy Granite lacks joints and other zones of weakness
and can form massive, magnificent blocks, which in 1825 had attracted the attention of Solomon Willard, the gallivanting Boston
architect-engineer.

Work began again on Bunker Hill Monument in April 1827, nearly two years after General Lafayette had placed the original cornerstone.
²⁶
(The box containing the bit of Plymouth Rock was reburied in a new cornerstone in the northeast corner.) One of the first
things Willard had to do was to figure out how to lift the massive blocks.
Working with local seaman Almoran Holmes, Willard
designed a massive hoist, or derrick, which consisted of a single wooden pole and a movable boom, attached by a block and
tackle.
Cables facilitated rotation of the boom, changing its angle, which determined reach.
Known as the Holmes Hoisting
Apparatus, it had a reach of fifty feet and, with six horses providing power, could lift up to twenty tons.
The derricks along
the edge of the Granite Railway Quarry were based on Holmes’s design.
Ironically, Holmes died several years later while using
one of his own derricks.

With Bryant’s railroad transporting blocks and the derrick lifting stones, workers were able to lay fourteen courses of the
monument, a height of thirty-seven feet, by February 1829.
²⁷
And then the Bunker Hill Monument Association’s money ran out, work stopped, and all employees, including Willard, were laid
off.
During the work break, the Granite Railway’s owners decided to open a new quarry on land about a half mile closer to
the Neponset than Willard’s quarry.
That land, which Perkins and his fellow railroad owners had purchased in 1826 for ten
thousand dollars, became the Granite Railway Quarry.