Greenfield Bridge brought down by explosives

Photo taken by Nathan Holth

93-year old historic bridge in dire straits put out of its misery together with a falsework bridge beneath it.

PITTSBURGH-  It was a posterboy of Pennsylvania’s infrastructure, touted as one of the worst in the country, but it was a classic example of a bridge whose life would have extended beyond a century, had the state and Allegheny County each contributed enough money for rehabilitating the structure. Now the Greenfield Bridge, a 1922 open spandrel concrete deck arch bridge has become a piece of history, and an example of wasted tax dollars that could have better been spent maintaining it!

Crews imploded the 142 meter long (466 ft.) bridge, a work of the local bridge builder E.M. Wichert, this morning, dropping it and the falsework bridge onto Interstate 376. The explosion took a few seconds, albeit the scheduled demo was delayed by 20 minutes due to intruders in the vicinity, according to the Pittsburgh Post Gazette. The bridge carried Beechwood Blvd, spanning I-376, located between Oakland and Squirrel Hill Tunnel. A video shows the bridge being brought down below:

The bridge had deteriorated to a point where planning for a new span began in 2010 for a new span. Yet, according to Nathan Holth of HistoricBridges.org, the deterioration could have been hindered had money been spent properly. “Countless historic bridges have been neglected and/or demolished and replaced for no other reason than that the system for funding bridge projects in the United States is severely flawed and encourages agencies to defer maintenance and rehabilitation until the bridge deteriorates to a serious condition, at which point those agencies are rewarded with demolition and full replacement funds from the federal government. This system has destroyed history, wasted tax dollars, and probably reduced safety as well,” he mentioned in his website. He later adds, “The system need considerable reform, so that greater quantities of funding are provided from the federal government to state and local agencies for the purpose of bridge maintenance and rehabilitation, thus reducing the need for costly, destructive, and inconvenient replacement projects. At the same time, state and local agencies should have to pay a larger percentage of the cost for replacing a bridge, which would decrease the incentive for deferring maintenance and letting a bridge deteriorate.” Because of concrete pieces falling off the bridge, a falsework bridge was built over the Interstate to catch the debris at a cost of $700,000, something Holth and other preservationists have considered a waste of money. That bridge was also brought down along with the arch bridge.

The Greenfield Bridge had been listed as one of 13 pre-1940 concrete arch bridges in the greater Pittsburgh area that needed attention as far as preservation and the National Register of Historic Places are concerned. Unfortunately, once the Interstate is cleared of all the debris from the wrecked bridges, a steel arch bridge will be put into place, expected to be open to traffic by the end of next year. According to sources, railings and other features will mimic the bridge lost to history. Yet it will never resemble the bridge that became a victim of a system in dire need of reform to reduce the amount of wasted money and preserve some history, something Pittsburgh has taken pride in with the city’s numerous bridges.

bhc new logo newsflyer

Book of the Month: The Colorado Street Bridge in Pasedena, California

Bridge Color Dusks
Lampposts of the Colorado Street Bridge in Pasadena. Photos courtesy of Tavo Olmos

Pasadena, California: with 138,540 inhabitants and a suburb of Los Angeles, the city is loaded with glamor and glitter, as the rich and famous make their homes there. Streets are lined with tall palm trees and loaded with cars. And there are famous landmarks that make the city the place to see, like the Pasadena Playhouse, the Ambassador Auditorium, Bungalow Heaven, the Rose Bowl (and the site of the Tournament of Roses Parade that takes place on New Year’s Day), and of course, the Colorado Street High Bridge.
While I have yet to see the bridge, along with the other structures in the City of Angels, I was approached by the publisher about doing a review of a book written by author Tavo Olmos on this particular bridge. Looking at the copy received by the folks at Pasadena, I am pleased to inform you that the wish is granted. This part will look at the book, while the next part will feature the interview by the author himself.
The Colorado Street Bridge was one of the most important works of Dr. John Alexander Low Waddell of the Kansas City-based bridge building firm Waddell and Harrington.  Before its completion in 1913, Waddell had already garner numerous accolades both in the United States as well as Europe and Asia, due to numerous bridges built during his 20-year career, plus numerous bridge design patents, like the Waddell truss, a subdivided form of the Kingpost truss bridge where there are only two of the through truss type and over a dozen pony truss types left in the country.  Waddell designed the arch bridge to make it aesthetically appealing to the city, yet the contract for actually building the bridge went to John Drake Mercereau, for cost-cutting purposes. The nearly 1428-foot long bridge was completed in over a year’s time in December 1913. Waddell would later build many gigantic structures over the next 25 years until his death in 1938.
Because of wear and tear and the fact that it was becoming functionally obsolete (because of the increase in the number and size of traffic), plans were in the making to replace the Colorado Street Bridge, starting with a freeway bridge in 1953 (known as the Arroyo Seco Viaduct), mimicking the design of the bridge. The bridge was closed to traffic in 1989, but on both occasions, citizens of Pasadena petitioned the city to find ways to preserve and restore the structure. After two years of politicking and campaigning, the city council in 1991 passed a resolution, providing millions of dollars in funding to restore the bridge, a process that took a year and a half to complete, from July 1991 until it finally opened to traffic in December 1993.
For those who have little knowledge of how an arch bridge like the Colorado Street Bridge can be restored, this book provides you with the restoration process described in pictures. During the restoration process, Tavo Olmos photographed the entire restoration process, from the start of the project, where the roadway was removed, to the time where the arches were retrofitted to increase its sturdiness and make them earthquake-resistant, to the completed work of widening the decking and adding the ornamental lighting.  Much of them were published in the book, published last year as part of the celebrations of the bridge’s 100th birthday. The book features some background information about the bridge and its dimensions, as well as its designer and bridge builder, before looking at the restoration process in pictures and the notes he took that were added in the book. Yet despite the fact that Olmos is a photographer, his book does not just feature photos of the entire restoration process. Articles written by people associated with the bridge and the project itself, which includes Claire Bogaard, the wife of the city mayor Bill Bogaard, members of the city public works, the city engineer and those involved with the project directly.  These articles were written in simple terms, describing the restoration process to the public in 2-4 pages that are easy to read and understand, if the reader is interested in knowing more about the restoration process.
Sometimes less is more and simplicity can speak more volumes than complication ever can offer. With the Colorado Street Bridge project, Olmos did not need to describe the process beyond what was shown in the pictures and notes supporting them, giving the reader the visualization of how bridge restoration works both in general if arch bridges are involved, but also in such a tall structure like Pasadena’s beloved icon. For preservationists and interested readers wanting to know how a bridge can be restored, it is highly recommended to buy/order this book, look at the pictures and read the comments from those behind the restoration process.
At 101 years of age, the bridge still lives on, both in pictures as well as in its original form. It is hoped that this book will provide a guidance where the bridge is an example of other bridges of its kind, both big and small, that can be restored if people have the efforts and manpower to conduct it. If not, the book has some history behind the bridge and how it became an integral part of Pasadena’s history.

Bird’s eye of the bridge at night.

 

Author’s Note: Tavo Olmos, whose photos were used for this article, was asked a few questions about the book by the Chronicles. The information from the interview is to follow. 

Book info:

Olmos, Tavo. The Colorado Street Bridge: Restoration Project Photographs 1991-1993  Pasadena, CA: Balcony Press, 2013

 

 

 

 

The Bridges of Des Moines Part II: The Arch Bridges

Court Avenue Bridge in Des Moines Unless noted, all photos taken by the author in August 2011

After a night photo tour of the bridges in Iowa’s state capital, the next segment will look at the arch bridges serving the city of 250,000. Like many cities in the US, these bridge types were successors to truss bridges built between 1870 and 1880 and made of either iron or steel. In one case, the predecessor was a Post through truss bridge, reported to have been the lone bridge of its kind built in the state. These bridges were built out of concrete, either made with gravel or clay. Two periods should be noted when the bridges were built: the one between 1909 and 1920, when these bridges were built using a closed spandrel design. Four of them were built using a combination of gravel and clay as materials, albeit three of them are still in service today. Then there was the period between 1918 and 1940, where the structures were built using the open spandrel design and gravel for concrete as materials. The Scott Avenue and the previously mentioned Meredith Bikeway Bridges are the youngest bridges that are still standing in Des Moines, each built in 1937 during the period of the Works Progress Administration. Most of the bridge construction were the work of a local bridge builder who became known for his patented rainbow arch bridges. James B. Marsh dominated the bridge building scenery, first while working for the King Bridge Company with its branch office in Des Moines and later as an independent entity known as the Marsh Bridge Company. While there is speculation that the Seventh Street Bridge over Raccoon River may have been built by him (judging by the arch design that is similar to the rainbow arch), he is credited for building four of the arch bridges in Des Moines, one of which was with the help of another bridge engineer, George Koss, whose business was (and still is)  located in Des Moines, as well.

All but two of these bridges are being renovated even as this article is being posted. The reason for this is to strengthen them against the floodwaters. This is all part of the long-term plan to ease flooding which had affected the city on four different occasions: 1993, 2008, 2011 and last year. How exactly will this be done remains to be seen, but already work is being carried out on the Scott Avenue Bridge at present. The plan is to rehabilitate the bridge one-by- one before 2020, while raising the dikes and the Red Bridge.  Two of the bridges are not affected, for the Grand Avenue Bridge over Walnut Creek has been replaced and the St. John’s Road Bridge is spared from the work because of its location away from the Raccoon River.

Despite the construction going on, one can see the bridges in their place while touring Des Moines, even though the best time to photograph them are either in the day time or on a cloudy evening when the city lights illuminate the skies. Here are the bridges worth seeing while in Des Moines (just click onto the names to get to the external links):

Locust Street Bridge:   The Locust Street Bridge has the reputation of being the only crossing to have been built twice by the same builder. James B. Marsh built the three-span Pratt through truss bridge in the 1880s while working for the King Bridge Company. He later replaced it with the present bridge in 1909. The bridge features a closed spandrel arch bridge with the gravel concrete arch being filled in with  brown-colored clay. The bridge is 447 feet long with six spans total. It was rehabilitated in 1967 as part of the urban renewal project and remnants can be seen on the bridge, going beyond the 60s-style street lamps. Yet it will not be long before a rehabilitation and renovation will come to this bridge, prolonging its life and making it more attractive.

Update: This bridge was replaced with a faux pa arch span in 2018

Court Avenue Bridge:
Located over the Des Moines River, this 496 foot long bridge features five spans of the closed spandrel arch bridge and is the most ornamental of the arch bridges in Des Moines. The bridge was designed by James Marsh and constructed by George Koss’s company in 1917 and serves as a key link between Des Moines’ city center and the State Capitol. The bridge was rehabilitated in 1986 as part of the construction project to redesign the street and eliminate the Capitol Hill Tunnel (the latter occurred in 1992). Today, it still serves as the important link between the two entities, with the lighting making it more attractive to photographers at night. This bridge replaced the Post through truss bridge built in the 1870s and is the only one known to have been built in Iowa thusfar.

Grand Avenue Bridges The Grand Avenue Bridges featured two closed spandrel arch bridges located within four miles of each other: the Walnut Creek Bridge, which was built in 1914 and featured two spans totalling 168 feet, and the Des Moines River crossing, built in 1918 and totalling 495 feet worth of six spans and looking identical to the Locust Street Bridge. The 1914 bridge was recently demolished and is being replaced at the time of this post, whereas the 1918 span is slated for extensive rehabilitation in the near future.

Update: The crossing over the Des Moines River was replaced with a faux pa arch span in 2017

Walnut Street Bridge: Spanning the Des Moines River, this bridge was one of four built by James Marsh and features a closed spandrel arch bridge design similar to the ones on Locust Street and Grand Avenue. The 1911 structure features five arches totalling 503 feet, yet like the Locust Street Bridge, it has seen better days since its rehabilitation in 1967 featuring modern railings and 60s-style street lamps. Yet with its next rehabilitation, it might change that state. Interesting fact is the fact that the bridge replaced a bowstring arch bridge built in 1871. Although unknown who the bridge builder was, it appeared to have been the longest bridge of its kind in the state and even surpassing the still exant Kern Bridge in Mankato in neighboring Minnesota. Evidence is needed to support this claim, though.

Scott Avenue Bridge  
The Scott Avenue Bridge is located over the Des Moines River at the junction of the Raccoon River and the Meredith Bikeway Bridge. Built in 1937, this bridge may have been part of the Works Progress Administration project, authorized by President Franklin D. Roosevelt to get people back into the work force. The five-span open spandrel arch bridge is 747 feet long and the thickness of the arch is similar to the Seventh Street Bridge spanning Raccoon River. But it is unknown whether Marsh, Koss or another bridge builder was responsible for building this bridge. During the visit in 2013, the bridge was closed to all traffic because of rehabilitation. But it did not stop those from making a stop at the nearby Mullet’s restaurant, which serves local specialties, including fish and the like.

Update: The bridge was renovated and reopened in 2014. It has been christened the Meredith Bridge, named after the company in Des Moines

Seventh Street Raccoon River Bridge 
The Seventh Street Bridge over Raccoon River is the second longest but the tallest of the deck arch bridges in Des Moines. Built in 1915, the bridge is 800 feet long with the height above water being over 40 feet. The bridge features a four-span open spandrel arch bridge which can be easily seen from a mile away. Yet the best photo opportunity can be found at the Fifth Street Pedestrian Bridge.

Photo taken by Daniel Barnes in 2018

University Avenue Bridge  
More information is needed for the University Avenue Bridge, located north of the I-235 Bridge. According to current data, the bridge was built in 1920, although when exactly it was built, let alone who built it was unknown. It is known that the bridge is an open spandrel arch bridge featuring seven arches, totalling 850 feet, making it the longest bridge of its type in Des Moines. Although not visible from the interstate bridge, one can see it from the bike trail going along the Des Moines River, which the bridge serves. The bridge serves as an important link between Drake University on the west end of the bridge and the Iowa State Fair, located two miles to the east.

Photo by Matt Marzan

St. John’s Road Bridge  Located over an unnamed creek north of Water Works Park, the St. John’s Road Bridge is famous for its ornamental bracings made of concrete, together with the rest of the one-span closed spandrel arch span. Built in 1900, the bridge is only 40 feet long, yet its features will make the driver pull over for a short photo opportunity.

While most of the arch bridges are still in use, the truss bridges on the other hand have disappeared in large numbers, making it very difficult to determine when they were built and who were the contractors for these metal bridges. In the third part of the series on Des Moines’ bridges, we’ll focus on the lost bridges of Des Moines but will feature the ones that were not mentioned but are still important parts of the city’s history. The bridges mentioned in the first and second part and the CGW Railroad Bridges will not be a part of this article for their histories have been mentioned already.

The Bridges of Des Moines, Iowa Part I: Night bridge photo tour

35633993_10214201151177006_3677238874418970624_n
Green Bridge at 5th Avenue Photo taken by Chris CJ Johnson

This bridge tour is the first of a three-part series that will focus on the bridges of Des Moines, Iowa, one of the main stops for this year’s Historic Bridge Weekend.

How many of you have a digital camera and enjoy taking photographs of places of interest at night? If you enjoy taking night photography as much as I do, what places have you gone to and spent extensive time taking some pics at night? And which objects are your favorite to photograph at night?

With the development of digital cameras and the invention of different ways to photograph places, the interest in taking night photographs has increased exponentially in the last decade for reasons that you can take as many pictures of places of interests from different angles, sort the pics out and take the best ones that you can take pride in. With the increase in interest in places of interests, many city designers have gone out of their way to light up the places of interest at night to encourage photographers to walk the streets at night and take some snaps digitally, as can be seen in a classic example with the city of Flensburg, Germany, where yours truly went wild over night photography in 2010 and 2011 and has an article with some samples to prove it. (click here to view the photos.)

The same applies to historic bridges as well, as many cities have accomodated pedestrians and cyclists with a set of lighting on the bridges not just for the purpose of safety but for the purpose of making them more attractive. This takes us to the city of Des Moines, Iowa’s state capital and one of our major stops during our historic bridge tour in August 2013. With a population of over 250,000 inhabitants (700,000 counting the metropolitan area, Saylorville region and Ankeny), the city has one of the highest densities of bridges in the Midwest, competing with Minneapolis-St. Paul, Sioux Falls, Quad Cities and even Chicago, just to name a few. A third of the bridges consists of those built in 1945 and earlier, but there are some substantial bridges that have been built with aesthetic appeal since 1990. And there are quite a few that are decorated with lighting, creating an “Aha-Effect” for people walking along the Des Moines or Raccoon Rivers, the two primary waterways serving the city.

Despite construction of a new floodwall along the river to prevent future flooding (the last ones occurring in 2010 and 2011) and one bridge closing due to structural concerns, we had an opportunity to tour some of the bridges in Des Moines and are providing you with a sneak peak of some of the bridges you can see while touring Des Moines, so that you can plan a future trip there and even take some pictures for yourself.

Jackson Street Bridge BH1
Fifth Avenue/ Jackson Street Pedestrian Bridge in Des Moines. Photo taken in August 2013

Jackson St. Bridge BH2
Side view of the Jackson Street Bridge.

Fifth Avenue Bridge over the Raccoon River: This 400-foot bridge can be seen easily from the 2nd Street Bridge, its replacement, with its white light illuminating on the color of lime green that covers the three-span Pratt through truss bridge. This bridge was built in 1898 by the King Bridge Company at the time the bridge building company was at its peak in its history. The portal bracing was later adopted by George E. King when he started his own business at the turn of the century. The bridge was converted to a bike trail crossing with a few benches for people to sit down. Yet sadly, the bridge has been closed to traffic since March of this year due to structural concerns. Still, one can  see the bridge lit up, providing an opportunity for many to pay homage to a piece of history. Hopefully the structural issues will be resolved so that it can be reopened again.

Meredith Bridge
Meredith Bike Trail Bridge

 

Meredith Bike Trail Bridge: Also known as the Water Street Bridge, this bridge represents a classic example of one of many deck arch bridges built in the 1930s (this one was built in 1937) that will be mentioned in Part II of the tour. Located over the Raccoon River at the confluence of the Des Moines River, the bridge serves the bike trail combs the west bank of the Des Moines River. City officials in 2006 allowed planners to convert a vehicular crossing into a park filled with vegetation and benches, allowing people to enjoy the view of Des Moines’ skyline, and pontists to spend time at that bridge as well as its adjacent Scott Avenue Bridge.  The bridge and its skyline can also be seen from Mullet’s restaurant, which is also located at the confluence and serves local specialties and fish entrées typical for the region.

Des Moines skyline
Des Moines skyline and Iowa Cubs baseball stadium. Taken from the Meredith Trail Bridge

Scott Avenue Bridge
Scott Avenue Bridge at sundown. Located adjacent to the Meredith Trail Bridge

MLK Bridge 4
Martin Luther King Bridge

Martin Luther King Bridge: Built in 2005 as part of the Parkway project honoring the civil rights activist, this crossing features two bridges, one for each direction of traffic, and blue lighting on the outer piers illuminating the Des Moines River. That combined with a row of white LED lighting gives the bridge a blue appearance. Though while work was going on at the bridge to raise the east bank, we were given a treat with this view of the arched piers reflecting off the bridge, reminding the author of the I-35W Bridge in Minneapolis.

red bridge
Red Bridge spanning the Des Moines River in Des Moines. Photo taken in August 2011

Red Bridge
Red Bridge

 

Red Bridge: Also known as the Norfolk and Western Bridge, this 500 foot long two span Pratt through truss bridge was built in 1891 and spans the Des Moines River. After the railroad abandoned its line and bridge in 1995, the city bought the bridge and integrated it into the Principal Walkway system in 2006, while giving the bridge a new deck, cherry red paint and mirror reflecting lights, giving the bridge a unique light red color that is appealing both day and night. Yet the bridge was not lit up during the visit in August and for a good reason: As part of the plan to raise the flood wall, the bridge will be raised by four feet to ensure that floodwaters pass through the city without incident. Already the decking was raised and it is expected that the truss spans will be raised by the middle of next year. Only afterwards will the bridge return to its original form, lit up for people to see again.

red bridge dm 2
Close-up of the Red Bridge and the decking already raised by four feet as part of the flood-prevention project.

 

Center Street Bridge 1
Center Street Bridge in Des Moines, Iowa (USA)

Center Street Pedestrian Bridge: This is the youngest and one of the fanciest of modern bridges in Des Moines. Built in 2010 as part of the 125th anniversary of the Principal Financial Group and the project to develop the bike trail, this steel through arch bridge features an arch suspended by still vertical cables, that serves as a divider for the decking designated for bike trail and pedestrian trail. From the air, the decking resembles a football. The bridge was shortlisted for the Bridge Engineering and Design 2011 Footbridge Awards. But it may be one of the bridges listed for this year’s Ammann Awards, not only because of its design but also because of its appearance at night. With the lighting illuminating the arch, which can be seen from I-235 and from the Red Bridge, it makes a perfect picture if taken with the skyline in the background, as shown above. Yet the dark side is the fact that the bridge may be the least safe of the bridges for it is a meeting place for gangs and violence. So when at the bridge at night, please take extra precaution to ensure your’re safe.

bot garden bridge
Botanical Garden Tied Arch Bridge

I-235 Tied Basket Handle Arch Bridges: The last stop on the night tour are the I-235 Tied Arch Bridges. Built in 2005 as part of the project to widen and improve the interstate through the city center, one will not miss the three blue and white-colored tied arch bridges located within a distance of three miles of each other. This is especially the case at nightfall when they are lit, providing a stark contrast to the yellow sodium street lamps that line up along the interestate.  The arch bridges are located as follows, driving westward:

Edna Griffin Memorial: between 6th Street exit (access avaiable there only) and the Des Moines River. Perfect site for a photo with the skyline in the background.

Center Street: east of 42nd Street exit. Access either at Center Street (south of I-235) or Rollins Avenue/ 40th Place (north of I-235)

Rider Way: West of 42nd Street exit. Access through Center Street at Roosevelt High School.

Rider Park B
Rider Park Bridge

 

If one has to sum up the night tour of the bridges in Des Moines in one word, it would be awesome. Each bridge has its own character which is illuminated quite clearly at night when driving past, making the driver spend some time at the structure taking some pictures. While it may take 2-3 hours to complete the tour, counting the walking in, it is one of the activities that one should take advantage of when visiting the city.

Yet the night tour is only a fraction of what a person can see for bridges in the state capital. When we go to part II of the tour of Des Moines’ bridges, we’ll take a look at the other historic bridges that are a must-see, namely the ones built of concrete and steel, namely, arch and truss bridges.

Author’s Note: More information on the bridges can be found by clicking on the underlined words, which will take you to your respective sites.

BHC logo

 

Mystery Bridge 21: Bahnhofsbruecke

Overview of the bridge, taken from the platform at Flensburg Railway Station. Photos taken in May 2010

While traveling through a small city, like Flensburg, Germany, it is very important to not only find the bridges that are well known by the majority of the population, but also those that are unknown by many, but have information on its history and significance to the area it serves that is to be discovered.  The Bahnhofsbruecke, located just north of Flensburg’s railway station is one of these structures that belong to the latter category.

Oblique view

The arch bridge that carries Schleswiger Strasse over the rail lines connecting the city with Denmark, Hamburg and Kiel, is one of the first structures you will see when getting off the train but before entering the underground corridor leading to the train station building.  It is unknown when the bridge was constructed, but judging by its physical appearance, combined with its wear and tear (with black marks underneath the arches and some erosion on the outside), it appeared that the bridge was constructed in the early 1920s, shortly after the construction of the train station building (that was built in 1919).  With the exception of the addition of railings and the street being widened to accommodate an increasing load of traffic, its historic integrity has remained unaltered.

Close-up of the inner part of the spandrel underneath the arch bridge.

Yet from an engineer’s point of view, the deck arch design on this bridge is deceiving. From the outside, the bridge has a closed-spandrel arch design, meaning the vertical columns supporting the arch and roadway are filled with either concrete or brick, making it the sturdiest of the deck arch designs. Yet after taking a closer look at the bridge, one can see that in all reality, it is an open-spandrel arch bridge, consisting of an arch bridge supported by just the vertical columns. The outer arch portion of the bridge is used as a facade to further support the road deck of the bridge. It is unknown whether it was added during rehabilitation of if it was originally part of the entire structure.

But independent of the engineering design, the Bahnhofsbruecke, the third longest bridge in Flensburg behind the Peelewat Viaduct (located southeast of the train station) and the viaduct along the Ostangente, lacks information on its history- namely, when it was actually built, who built it and whether any modifications were made on it in order for the bridge to be functional for traffic. And this is where your help is needed.

Any information on this bridge? You can comment on it at the end of the article, post it on the facebook page under the Bridgehunter’s Chronicles or contact the author directly at flensburg.bridgehunter.av@googlemail.com.  Once the information is collected, the bridge will be profiled as the Chronicles will tour the bridges of the rum capital of the world, the city by the bay known as Flensburg.

You can also view the film with the author’s commentary, which can be found here.