c.1846 engraving, new armory at leftIn 1846, Windsor Vermont gunmakers Robbins, Kendall and Lawrence took the bold step of bidding on a government contract for rifles with interchangeable parts. They were running a small shop, using a combination of machinery and hand-crafting. The new contract, for 10,000 rifles, would require more workers, more machinery, and larger quarters. On the south side of Mill Brook, they constructed a handsome, four-story brick armory building.

Using and improving upon the latest machinery available, the tiny firm grew rapidly, attracting the best designers and machinists and creating a center of excellence in the Connecticut River valley. They soon earned international acclaim for the quality of their guns and the efficiency of their machine tools. Although the small firm foundered within about a decade, the mechanics and inventors they trained spread across the country, taking the machines and the concept of interchangeability, along with their inventive spirit, to other towns and other industries.

Building exterior, approximately 1970

When Ed Battison founded the museum in 1966 one of his first projects was ensuring that the Robbins and Lawrence armory was designated a National Historic Landmark, based on its cultural significance and architectural integrity. The building is a classic example of mid-19th century factory architecture, constructed of handmade brick with interior timber framing. The adjacent Mill Brook provided the water power to run the machinery, diverted to a mill race and water wheel in the basement.

The museum began the restoration process anew in 1999 with a Conservation Assessment Program survey.in 2003 examination of the roof using a lift truck revealed that the slate roof shingles were loose on their fasteners, inviting water to rot the wood shingles below the slates and causing major leaks in the attic. Students in the University of Vermont's graduate program in Historic Preservation completed a study of each of the building's 166 historic wood windows. Preservation architect Tom Keefe crafted a plan to put on a new slate roof and address 60 windows that were in the worst condition.

APM applied for and received a Save America’s Treasures matching grant of $200,000. The grant agreement required strict adherence to the highest preservation standards. The museum raised the matching funds with support from Preservation Trust of Vermont in partnership with the Freeman Foundation, Vermont Housing and Conservation Board, Timken Foundation, other private foundations and many generous individual donors—a total of $458,000.

We developed two separate contracts, one with a roofing contractor and one with a windows preservation specialist, requiring them both to share the scaffolding, which was an expensive part of the total project. The 60 windows were selected using two criteria: those in the worst condition, and those most difficult to access, primarily on the upper floors on the steep north facade.

In July 2005, the new roof and 70, not 60, windows were completed, along with some stabilization work. There was money left over to do an engineering assessment to address interior structural issues.

The building had been overloaded in prior years, causing damage to posts and beams throughout all of the upper floors. There were also inherent structural deficiencies in the cupola framing. The structural repairs were completed in 2007 thanks to Vermont Division for Historic Preservation and Mascoma Savings Bank.

It’s a good idea to improve safety and access, while moving forward with building preservation work. With funds from the Vermont Arts Council Cultural Facilities Program we removed a raised floor at the west end that had been created when the building was used as a truck garage, added handrails in the stair tower, and reinstalled the crane used to move heavy machinery in and out through newly built loading doors at the west end.

With help from The 1772 Foundation, restoration of the windows in the east wing was completed in 2008, leaving only the south side windows to do. Unlike the upper windows that required scaffolding, those along the south wall are easily accessible from the ground or by lift truck.

The building's moisture problems will continue to adversely affect the building and collections if not corrected. Before proceeding with any plans to address these issues, we engaged the Historic American Engineering Record to complete a study of the building's historic fabric especially relating to the waterpower system. The Society for Industrial Archaeology and other generous donors provided support. The basement of the main block still contains the remains of the gearing frame that supported the 18' diameter breast wheel (long gone), and the waterwheel pit, approximately 19' deep and 18' across. The report was completed in 2009. It includes photos, interpretive drawings and a thorough descriptive narrative and is available at Library of Congress American Memory, and printed in book form at the Museum Shop. Interpretive drawings from the study were reproduced as an exhibit.

In 2009, careful digging at the rear of the building uncovered enough evidence to determine the location, direction and general configuration of the head race. The headrace trench is carved out of ledge to be about 5-6 feet wide and with its sidewalls tapered to about a 45 degree angle. The dig confirmed that water entry at the west wall is not a new problem. The head race trench may have been lined by a wood penstock system to limit leakage.

Since 2005 APM staff has monitored environmental conditions from basement to attic. The waterpower study completed in 2009 provided more information about intact historic fabric. The building's moisture problems will continue to adversely affect the building and collection if not corrected. The National Endowment for the Humanities National Endowment for the Humanities awarded us a planning grant to help bring together a conservator, a historic preservation architect, a civil engineer, and a mechanical engineer to explore solutions. NEH selected our application as a model project and posted it as a sample application narrative.

Portland cement can adhere tenaciously to porous masonry, but is also known to shrink away while curing, leaving gaps that admit water. In this case the integrity of the wall is being undermined. Photo by Tom KeefeThe armory building was constructed by hand using locally-made brick and traditional soft lime mortar. The soft mortar is designed to be sacrificial, weathering away with age and needing re-pointing about every 30 years. The building has 12" thick load-bearing masonry walls with no cavity, exposing brick as the finish on both the exterior and interior surfaces of the walls. The exterior has been re-pointed several times, and all re-pointing appears to have been done with a hard Portland cement mortar.

Mortars made with Portland cement develop strength and rigidity many times greater than the soft lime mortars typically used in 18th and 19th century masonry. When hard Portland mortar is introduced, the stresses are re-directed to the relatively-soft bricks, which become ground down and broken, leading to expensive repairs and loss of historic material. For this reason preservation standards prescribe testing and use of mortars compatible in hardness with the original, taking into account the masonry material being bonded.

In 2008 we developed a masonry restoration plan. The criteria for evaluation and recommendations for a phased repair were as follows: Highest Priority – safety issues, like loose brick or imminent deterioration; 2nd Priority – weather tightness of building; 3rd Priority – construction issues e.g. staging/access, power lines; logical break points between phases of repair. Overall, the masonry restoration project is estimated at $1.2M.

This brick panel installed earlier to block up a window opening was stabilized with a tie rod through the wall to the framing inside the building. Photo by Tom KeefeThe project to address the unstable masonry was completed in 2009, thanks to a grant from Vermont Division for Historic Preservation. We accomplished more than we anticipated. Several small areas were fixed permanently, not merely stabilized. Fundraising is ongoing for the rest of the building's masonry. We will continue to break this large project down into more manageable smaller chunks and proceed as fundraising allows.

Morris Group, Inc. kicked off its 70th year celebration with a $100,000 gift to the museum to be used to create a new outdoor interpretive space in memory of Dorothy Morris, a cofounder of the company, who passed away in 2009.

The project completed in August included a major re-grade of the site to create a brick path appropriately sloped for wheelchairs and a sitting area overlooking the Mill Brook. Outfitted with granite steps and benches and new plantings, the new work encouraged visitors to enjoy the entire site, not just the exhibits inside the museum.

Below the new grade line, we completed work to help extend the building's life. To collect and divert roof runoff and surface water away from the building, a rubber membrane was affixed to the north wall of the wing and east wall of the main block, and drainage pipes were installed. Minor masonry repairs were also completed.

Tropical Storm Irene wreaked havoc in Vermont on August 28, 2011. The Mill Brook came crashing over the retaining wall by the museum leaving significant damage behind. The basement was briefly flooded; no artifacts were affected. A preliminary engineering assessment indicates there was no permanent damage to the building, because the water came up evenly on both sides of the walls. The same cannot be said for the retaining wall, which aged considerably due to the scouring effects of the flood. Most sadly, the beautiful new landscaping completed just two weeks earlier, was largely washed away.

As we work with town, regional, state and federal partners to repair and rebuild, we will also be looking for ways to protect our site and our village and mitigate against future natural disasters. We feel extremely fortunate that at our site, no one was hurt and the damage is repairable, unlike at so many other places in Vermont.