Monday, May 21, 2012

The following is a guest blog post by Phoebe A. Cohen, Ph.D. Phoebe is currently the Education and Outreach Lead and Post-Doctoral Associate at the MIT NASA Astrobiology Program at MIT. Starting in July she will be Professor of Geoscience at  Williams College. Phoebe is also the daughter of Board Vice President Carl M. Cohen.


 

 

More than we bargained for? 570 million years of history beneath the Durant Kenrick House.


I grew up on Magnolia Avenue, in an old Victorian house where my parents still live today. It was a wonderful place to be a kid – a golf course for sledding just down the street, a big back yard for playing, and an old red house on the other side of the block. That red house is the Durant-Kenrick house, and when I was growing up it was hard to get a look inside. We did go in at least once however, and I remember the creaking floorboards, a huge wooden chest that I imagined was filled with wondrous treasures, low ceilings, and a sense that I was walking into a past world about which I knew very little but desperately wanted to know more.

Cut to about 15 years later and I returned to the Boston area to start a PhD program in paleontology at Harvard University. I had never been very much into rocks and fossils as a kid, being more interested in wolves and foxes, but my fascination with the history of life on Earth had grown during my undergraduate years to the point where I decided to devote my professional life to the study of Earth’s past. As I progressed through my graduate work, my academic focus fell squarely on a time known as the Neoproterozoic – a time period ranging from 1,000 million years ago when the world’s continents were barren and life in the oceans was diverse but microscopic, to 543 million years ago, when the world’s oceans rather suddenly became replete with animals and plant life, an event known as the Cambrian explosion.

In my time as a scientist, I have traveled all over the world - Namibia, the Yukon, Australia, Death Valley, Newfoundland  - to study  Neoproterozoic rocks and the fossils they contain –. So in essence, not much had changed – I still wanted to learn about the past, I had just ended up WAY further back in time than the age of the DK house -- or so I thought.

About three weeks ago my boyfriend Zeke and I went to Newton to my parent’s house for a Sunday dinner consisting of my dad’s incredible thin crust style pizza. Over the crunch of crusts, my dad gave us an update on the ‘DK’ project and the classroom and storage space that was being built. He mentioned that  in the course of digging the foundation for the classroom and storage space, the construction crew had encountered  a minor  inconvenience – a deep layer of rock starting just 2 feet below the surface! . My dad started describing the rock to me, and my brain started to tingle. Once he showed me a few photos he had snapped, I was hooked. What he was showing me were sedimentary rocks. The reason this was so exciting to me is that of the three major rocks type, igneous, metamorphic, and sedimentary, the latter is the only kind that can preserve fossils. So my mind suddenly wandered to the possibility that the rocks underneath the DK house, and thus underneath my own childhood home, might contain fossils.



A portion of the excavation, showing at the top about 18" of earth with sedimentary rock below.

The next day I set to work researching the geology of Newton and the Boston area. At some point I’m sure I learned something about this, but it might not have been since the 7th grade, the last time most students in Newton take Earth Science. I had been lucky enough to take a half-semester elective course on geology and astronomy at Newton North, but even that was ages ago. Since I had become a professional scientist, I had never thought about what rocks might lie under my childhood home – until now.  What I discovered after a little time spent on Google Scholar and the United States Geological Survey website shocked me. Not only were the rocks under my neighborhood sedimentary, they were Neoproterozoic. So it turns out that the rocks that I have devoted my professional career to studying are the very same rocks that lay beneath the house where I spent the first 18 years of my life.

The rocks are in a formation that is known as the Cambridge argillite or the Cambridge slate. An argillite is basically a big mass of mud and clay deposited at the bottom of an ancient ocean basin that has, over millions of years, turned into rock. The DK  argillite is a part of a larger group of rocks known as the Boston Bay Group, which consists of familiar-sounding units including the Brookline and Dorchester members. Radiometric dating of these rocks by scientists from Wellesley College and MIT shows that the Cambridge Argillite is between 570 and 595 million years old – from the latest part of the Neoproterozoic. In general, the rocks of the Boston Bay Group record a period of dramatic change in Earth’s history during which levels of oxygen in the world’s oceans began to rise, which set the stage for the radiation of animal life in the Cambrian.

Much to my delight, it turns out that decades ago a young graduate student at Harvard University in the same lab that my advisor eventually got his degree from had looked at some of these rocks for evidence of microscopic fossils and found some! Admittedly the fossils they found are somewhat scrappy and not earth shattering, but nonetheless, I was thrilled. I quickly called my dad and asked that he go over to the build site before they poured the concrete foundation to get me some samples of the rock. So now there is a (very heavy) bag of Cambridge argillite sitting in my office. This fall I plan to take small pieces of the rock and dissolve it in hydrofluoric acid (HF). . The HF breaks apart the rock itself but leaves behind organic matter, including any organic-walled microfossils that might be inside. These microfossils likely represent the tough external coatings of single-celled algae and other protists, evidence of the microscopic communities that thrived in the same oceans where the first early animals were beginning to evolve.

It still amazes me that I never realized what rocks lay beneath the bucolic tree-lined streets of my own neighborhood until just recently. It reminds me that no matter how far you travel and how much you think you know, there is always more to learn and more to explore. This discovery also makes me wonder what magic the DK house and the rocks it sits on worked during my childhood years that helped to put me where I am today – a woman fascinated by reconstructing the past.

Phoebe A. Cohen

Friday, March 16, 2012

The beginning of the beginnng


Durant-Kenrick Blog March 16, 2012
After a long dormant winter (referring to the season rather than the weather) the Durant-Kenrick property has suddenly sprouted an early spring crop of backhoes, chain link fences and people in work boots!
Photo 1) Moving the dairy foundation
Photo 2.) The temporary location of the dairy foundation
We are about to receive our building permit for renovation and construction on the D-K property, and with the OK of the Inspectional Service Department, this week we have begun significant pre-construction activities on the property. Our general contractor rolled his state-of the-art trailer/office onto the site in preparation for groundbreaking.  The first order of business was to dig up and re-locate the foundation and floor of the “dairy” structure that we unexpectedly uncovered last summer.  After painstakingly marking and identifying each brick and foundation stone, and recording their exact locations, the crew used hand tools to carefully remove each brick and stone and relocate them to the back of the property (Photo 1: moving the dairy foundation; Photo 2: The temporary location of the dairy foundation).  These will eventually be re-assembled to re-create the dairy near the house some time after restoration and construction is complete.
Photo 3.) Partially excavated foundation of classroom/education center
Next, those aforementioned backhoes scooped out the top 18” of soil from the area where the new classroom/education center will be built (Photo 3: partially excavated foundation).  The excavated area is being examined by our archaeological sleuths from the UMass Boston archaeology department to make sure we’re not about to dig up or otherwise damage any yet-to-be found sub-surface structures or relics of days gone by. Once they give us the go-ahead we will begin full-scale excavation for the new wing.
Photo 4.) The support beams of the second floor 
Photo 5.) Portion of sill
In the meantime our restoration crew will soon begin work on strengthening some of the main support beams under the floors of the historic house (Photo 4.exposing the support beams for the second floor), and examining the integrity of the sills – the now ancient wooden beams that rest on the house’s stone foundation and tether the main vertical structural elements (Photo 5: portion of sill).  
If everything goes according to plan, construction and restoration will proceed through the spring and summer and should be substantially complete by early fall.  Of course with a nearly 300-year-old structure, there are a lot of unknowns.  Keep your eye on this blog and we’ll keep you updated on construction progress on a fairly frequent basis now that things are moving!
Carl M. Cohen

Thursday, December 22, 2011

Durant-Kenrick Blog – Third installment.

Now that the leaves are completely gone, each morning I can look out my back window and see the white tarp covering the back of the Durant-Kenrick House like a minor Christo installation.  From this perspective one could be forgiven for thinking that not much has been going on with Historic Newton’s biggest project in years.  But one would be mistaken, because great things are happening – how about three dozen historic corn cobs to start?

A couple of months ago Historic Newton engaged Tom Barber, a carpenter specializing in restoration of historic structures,  to do some exploratory surgery on the ceilings of the Durant-Kenrick House.  Tom needed to expose the main support beams for the second floor of the house so our structural engineers could determine whether they were sound and, if so, just how many excited third-graders we could allow into the second floor rooms at any given time.    In the picture below, Tom has exposed  the main beam above the ceiling in what would have been the parlor  (see below).


This beam is referred to as a “summer” or “sommer”  beam. The word is derived from the low Latin salma, meaning to pack or burden, in reference to the fact that this beam carries the load of the floor joists (via mortise and tennon attachments).  Summer beam construction was apparently quite common in houses of this era.  To get an idea of the impressive heft of these beams, check out this link (http://www.oldwoodworkshop.com/salvaged_wood_47.html ) to a Connecticut-based wood salvage company selling a 14’ long summer beam salvaged from a 1680s house in Wabam (sic) MA for $4,500.  

Fortunately for us, our engineers found the structural beams in the Durant-Kenrick House to be in good condition.   But in the process of performing the surgical incisions into the ceiling and poking about between the joists, Tom discovered a hidden trove of historic corn cobs  – dozens of them in fact – which were harvested into a Whole Foods shopping bag (see Tom with one corn cob).   
        

We haven’t subjected the corn cobs to rigorous archeological analysis, but the smart money is on squirrels, who must have had quite a gluttonous feast of corn judging by the stash.  It’s amusing to think that while the Durants or Kenricks were dumping their trash somewhere outside the house, the squirrels were busy dragging it right back in.

Well, the squirrels aren’t the only creatures who have been busy.  Out of the public eye, Historic Newton has been busy as well.  In the nuts and bolts arena, we have now received bids from four qualified contractors to do the work of restoring the historic house and of constructing the new educational wing. We expect to have chosen a contractor by early in the new year, and that construction will start sometime in February.    

Also, lots of administrative matters that make really tiresome reading, but which are of immense importance to making this project a reality, have been completed – including finalizing the preservation restriction agreement on the house and property, a key step in enabling us to receive approximately $1.27 MM from the City of Newton’s Community Preservation Fund.  A key milestone for the project was reached on Thursday, December 22, when Historic Newton received a check for this amount, the first installment of these funds, at a ceremony in Mayor Warren’s office.  Historic Newton is eligible for another $1.44 MM in funds to be used toward the rehabilitation and restoration of the Durant-Kenrick House. 

More good news on the financial front is that Historic Newton will be the recipient of a $100,000 challenge grant for the Durant-Kenrick Project from the National Endowment for the Humanities (NEH).  For months, our Director, Cindy Stone, has been telling us how difficult it is to get these grants, not wanting to get our hopes up.  This is a very prestigious award and we hope that it serves as yet another validation of the importance of this project for all of our fellow Newtonians. We hope that when you receive our year-end solicitation to help us complete the final lap of our fundraising campaign, you will see as much value in this project as those who have already given their generous support.  

Carl M Cohen
Vice President, Historic Newton Board

Friday, September 23, 2011

Subterranean goings-on at the Durant-Kenrick House

The remains of the dairy
Historic Newton board and staff tour the dig
If you were driving past the corner of Waverley Ave. and Kenrick St. during May and June, you might have noticed some odd goings-on at the Durant-Kenrick property.  At times as many as a dozen people could be seen busily digging holes (using what looked like tea spoons and pastry brushes!), writing intently in water-proof notebooks, working on ruggedized laptops balanced on the hood of a Subaru Outback, and planting tiny multicolored flags all over the place.  Most baffling was the strange four-wheeled contraption they would periodically pull back and forth across the grass and muddy earth. It looked something like a cross between a squashed lunar rover and a go-cart. Who were these strange beings and what were they doing at the Durant-Kenrick House?  Welcome to the world of suburban archaeology. 

The busy people were staff and students from the Fiske Center for Archaeological Research at UMass Boston, and they were there on behalf of Historic Newton, helping us figure out what, if anything, lay beneath the earth at our newest acquisition.  In case you didn’t know, and I certainly didn’t until a few years ago, if you’re planning to do any kind of digging or disturbing the ground on a historic site (and the Durant-Kenrick House is nothing if not historic), you need to make sure that you’re not about to inadvertently disturb buried historic treasures (Indian burial grounds? Historic foundations? An entire village?). 

When I first heard of this requirement, I reacted with dismay.  This would delay the project and cost money, and for what?  Three years later, I now know for what.  On a drizzly June day, a small group of Gore-Tex clad board members showed up to witness first-hand what the archaeologists’ painstaking excavations had revealed.  

As it turned out, the squashed lunar rover was actually a sophisticated ground-penetrating radar device that had detected and mapped (with the help of the Subaru-perched laptops) all manner of underground artifacts on the site. These included the stone structure of a back-yard well, some stone footings from a large but long-gone barn, and, most spectacularly, the intricate brick floor and foundation of a rather mysterious building that would have stood adjacent or attached to the north-east corner of the house in the early 1800s. 
 
After some research and consultation with their archaeologist colleagues, the UMass team decided that what they had uncovered was what they refer to as a “dairy.”  This would have been a structure (almost certainly wooden) built on the foundation stones shown in the picture above. The floor of the dairy, comprised of tightly nested bricks, was about 1 foot or so below ground level.  This arrangement helped keep the temperature inside the structure cool; the brick floor would have also helped to make the inside easy to keep clean.  In the
early 19th century, the building would have had low shelves on which wooden trays or bowls would be placed for storage of milk, cream, and butter. The fact that the structure was adjacent to the house just where the kitchen was located further supports these ideas. 

This discovery was both exciting and vexing.  Exciting, because it exposed a new dimension of life in the 1800s.  The staff at Historic Newton were and are energized by the possibilities for making this structure part of the educational experience being planned for the D-K house.  Vexing, because the dairy was located precisely where a new structure connecting the historic house and the new educational wing is to be built.  Modifying that plan this late in the game would mean lost time (many months) and considerable expense. 

After much thoughtful debate, it was decided to disassemble the dairy stone-by-stone, after carefully marking and mapping each stone and brick, so the structure could be re-assembled elsewhere on the site at a later date.  Our hope is that we will be able to re-create not just the historic foundation but also to construct a replica or facsimile of the dairy superstructure.  As of this writing, the dairy foundation is still where it has been for almost 200 years, waiting patiently to tell its story to future visitors.

Wednesday, August 17, 2011

The Durant-Kenrick House: A Blog by Carl M. Cohen August 16, 2011

The Durant-Kenrick House:  A Blog by Carl M. Cohen

It’s been a busy summer at the Durant-Kenrick house.  The Newton Historical Society took formal possession of the house and property in May, and, over time, we have had key meetings with the Newton Historical Commission, the Land Use Committee of the Board of Aldermen, the Mayor’s Committee for People with Disabilities, and the Massachusetts Architectural Access Board.  While more meetings are forthcoming, the net result is that all systems are go for this great project to move ahead according to plan.

For those of you who haven’t been living and breathing this project, here is a brief capsule summary of how we got here: The historic Durant-Kenrick house (circa 1732) and adjacent land at the corner of Waverley Ave. and Kenrick St. have been donated  to the Society through the generosity of the families that have owned the property for generations.  The Society sees this as a once-in-a-lifetime opportunity to preserve this unique historic structure that has a deep connection to both local and national history.  The Society’s goal is to make the house and grounds into a museum/education center highlighting the property’s  history, its agricultural saga (apples, pears and silkworms meet New England winter!), and the lives of the people who lived there.  The plans for the property involve restoration of the historic structure, including handicap access, and the addition of a new attached educational facility, including a classroom.  To take advantage of the beautiful property on which the house sits, we are working with Lucinda Brockway, a well-known historical landscape designer, to develop plans for the outdoor areas. These will likely include such features as historically appropriate plantings and garden areas representative of what might have been found at the house in the 18th and 19th centuries.  
Plans are already underway for incorporating the DK house and grounds and the stories of the people who lived there into the history curriculum of third graders of Newton.  This will include visits to the house and grounds, enabling students to see and experience a place in their community that connects to the founding of our country and illustrates the way life, agriculture, and commerce were carried out in the 18th and 19th centuries.

After working for many months with what we inelegantly call the “Durant-Kenrick Transition Committee” (board members and others who have been overseeing the project) our architects have a nearly complete plan for the new addition to the historic house. Also, the architects and engineers have been examining the historic structure to determine how best to restore it and repair what we hope are minor issues.  Any of you who have ever undertaken the repair or restoration of a house even half as old as this one know that we all have our fingers crossed.

As a neighbor of the DK House (I can see the DK house from my back porch!) I am extraordinarily gratified that the project has arrived at this point.  Six years ago when the NHS first learned that the property might be available, those involved had high hopes, but no idea whether they could make this happen or not.  While our fundraising efforts continue, the project is now well on its way thanks to the overwhelming support of the Newton community, neighbors, state and local funding agencies and many generous donors. 

Finally, in preparation for laying the foundation for the new classroom and walkways, we have been working with a group of archaeologists from the Fiske Center for Archaeological Research at UMass Boston to ensure that we will not disturb possible historic artifacts or features in the ground where work is planned.  In June the archaeologists completed their initial survey of the property and have submitted a report to the DK Transition Committee for review.  Next Month: Unexpected and exciting discoveries under 2 feet of earth!

Carl M. Cohen
Vice President
Newton Historical Society