The Zen of laying up stone
D&L Trail Tender Steve Krentler demonstrates how to lay a stone wall as he repairs a damaged section of the Lehigh Canal in Freemansburg.
Along with building the 165-mile Delaware & Lehigh Trail, the Delaware and Lehigh National Heritage Corridor's Trail Tenders have been working to preserve the historical places along the canal corridor.
In the Freemansburg borough, along the Lehigh River just east of Bethlehem, is the heritage site of Canal Lock 44 - consisting of a canal and canal lock, a locktender's house, a mule barn, and a mill raceway.
Since the Lehigh Canal was completed in the late 1820s, it was used primarily to ship anthracite coal to Philadelphia. As the mule-pulled canal boats approached the lock at about 3 miles per hour, the wakes would cause the sides of the canal to erode, and so in those sections, the walls were lined with a layer of laid-up stone.
Over nearly two centuries, from wear and tear from the ground moving and pushing, freezing and storing, from people climbing down the sides of the canal, and from roots pressing against the walls, and even more so since the canal bed has been dewatered, and with no water pressing against the stone to hold it in place, and no water to prevent the foundation of the wall from freezing, sections of the wall have collapsed.
The canal was abandoned around 1940, and has had minimum maintenance until, in the last 25 years, and with interest in historical preservation associated with the corridor, and most recently with the Trail Tenders, volunteers began helping to restore portions of the canal.
On Saturday, April 6, D&L Trail Tender Steve Krentler led a stone wall repair workshop on the upstream entrance to Canal Lock 44. Krentler begin with a safety talk cautioning members of the workshop of the hazards of working with stone. "Watch your back," he began. "Everything you pick up is going to be heavy. This is limestone. It is dense and quite hard. If you pick it up and drop it on your foot, or if your finger gets caught between two big stones, it's going to hurt. Bend from your knees, not from your back. Don't pick up things that you don't think you can lift. I've learned that the hard way."
He pointed out that it was essential to wear heavy duty gloves, and even heavy duty gloves would wear out in a few hours. So he came up with a tip - wrap the fingertips of the glove with duct tape. "Without the tape on the glove's fingers, you will wear through the gloves in about two hours. Then you will be wearing down your skin."
Before beginning, Krentler asked members of the workshop to look at the portions of the canal wall that were in good condition. "Our reference library is these old stone walls surrounding us."
"We are standing in front of a retaining wall that was originally built with cut limestone, and dry laid meaning no mortar was placed in-between the stones. The canal is dry, so therefore it does not have the forces of the water helping to hold it up, so it has collapsed in a few places."
Krentler then directed members of the workshop to begin removing the fallen stones, move it about 20 feet from the wall, and spread out in an arc with the good side facing up. These stones will form the random puzzle pieces to reconstruct the wall. Then, the remaining excess soil was removed and stacked.
From the arc of stones, Krentler selected a large stone and set it so that the top of the stone was horizontal and flat. He then used smaller stones to prop it into position. Next, he selects a smaller stone at about the same height, and again uses smaller stones to position it to the right height and angle. He used a trowel to tap the stones into place.
The rock that Krentler reused was a sedimentary form of limestone. Since sedimentary rock was formed in layers, he said, "Make sure the sedimentary rock is placed horizontally."
"It's like a puzzle," he noted. "Make sure each stone locks into place and doesn't wobble."
"There is a rhythm to doing it. If I take a day or two off from work, and work on it for three or four days, I will get as much done the last day as I did the first two days. I get into it."
"There's a Zen to laying up stone. I find that it clears my head. I can't be thinking about other things, problems, work. It becomes meditative."
"My wife will come out and say, 'Do you want lunch?' She will repeat it three times, each time becoming increasingly louder, and I will be laying the stone, totally oblivious."
Krentler's own stone house is near lock 45. "Stone walls all over the place. Even if I could find someone to repair the walls, it would cost quite a bit of money. I do them the myself. It's a great workout. The material is laying there, so it really doesn't cost much except a couple of ibuprofen to ease the back pain."
"My tools are mostly my brain and muscles, with a little help from a digging bar, a shovel, a trowel and a good pair of work gloves. I have rebuilt 30-foot sections of four foot-high stone wall by myself in a couple of weeks."
"I can't afford to pay somebody to do it because this is not easy work. When I was asked how I learned to lay stone, I replied that I just looked at the walls, I read a book, and I talked to a couple of old timers."
"People have tried to hire me to work on their houses. I said, 'Are you crazy?' I love it and I hate it. I wouldn't want to do this every day. It wouldn't be special anymore. It would be work."
To learn about the D&L Trail Tender's, contact Dennis Scholl, email: email@example.com or 610-923-3548 x225.