Museum Conservation

Colonial Instruments now offers museum conservation work on 18th century surveying instruments from England and the American colonies in addition to 18th and 19th century microscopes from England, Europe and the United States. Our conservation work maintains the integrity of the original instrument and we provide proper documentation of the whole process, including any replaced pieces.

The types of conservation work we perform are:

  • Patination Restoration – re-patinating of previously polished areas
  • Oxidation Correction – removal and stabilization of oxidized areas, preventing erosion of the original brass surface
  • Manufacture – creation and replacement of missing or incorrect elements on the instrument
  • Re-Assembly – re-assembly of instruments to correct errors from work done on the instrument previously

Since each museum’s needs are different, please contact us to discuss your project.

Museum Testimonials

bird-jeff“Jeff did an amazing job researching and reconstructing the missing components of the 1763 John Bird transit and equal altitude instrument originally used by Mason and Dixon for their survey and now under the care of Independence National Historical Park in Philadelphia PA. Jeff’s knowledge and skill brought our project home; without his exacting attention to detail, his unflagging support, and his scholarly dedication, the restored Bird transit wouldn’t be available to the public today.”

Conservation Workshop Heath

Performing conservation work on the mid-18th century telescopic theodolite by Thomas Heath from the Penn family collection.

“Jeff Lock’s knowledge of 18th century surveying instruments is impressively vast and is only surpassed by his infectious passion on the topic. Having a conversation with him about these instruments is like reading a very engaging and expressive encyclopedic entry. We have been very happy with the work he has done on surveying objects in our collection and will continue to seek out his knowledge and skills again and again.”

Mary Grace Wahl
Project Director for Collections Care and Management
American Philosophical Society Museum



Important twin ring vernier compass by John Heilig, similar to the work performed by Benjamin and David Rittenhouse.

“I first met Jeff in the spring of 2010 when he came to the Schwenkfelder Library & Heritage Center to examine the John Heilig 18th century Vernier compass in our collection.

Jeff was able to take our compass apart quickly and carefully, and examine it for condition problems.

It is very important to me as a curator that minimal cosmetic work is done on a collection’s objects, and Jeff is of the same mind.

I was very pleased with the outcome. The oxidation had been removed, and the patina not altered. Additionally, he had made a replacement screw that matched the original. Also, I feel very comfortable asking Jeff questions when they arise, and knowing that he will always be patient and generous with sharing his expertise. All in all, an excellent experience, and I would recommend his services without reservation.”

Candace Kintzer Perry
Schwenkfelder Library & Heritage Center
Pennsburg, Pennsylvania


Performing conservation work on the David Rittenhouse surveyor’s compass in the collection of the Germantown Historical Society.

“On behalf of the Board of Directors, it is with great pleasure and gratitude that I thank you for the amazing work you did on our David Rittenhouse surveyor’s compass. While subtle, your careful restoration of the patina has only further enhanced the beauty and interest of what was already a truly special part of our collections.

In particular I am impressed with the care with which you removed the old, drippy shellac and the patient process used to unify the aged look of the brass. Your respect for the object and its history is clear and greatly appreciated.

I look forward to future opportunities to work together, and would be delighted to discuss our experience with others, serving as a reference if necessary. Please do not hesitate to contact me.”

Laura Beardsley
Executive Director
Germantown Historical Society

Moore C. Collection#171E5D1

Selection of surveying compasses by Camm Moore in an unusual variety of sizes.

“Jeff Lock contacted me in January 2010 about a compass made by Camm Moore of Guilford, North Carolina. He had one in his shop by this silversmith and was eager to see other examples and learn more about this relatively unknown artisan. When I explained to Jeff that the Greensboro Historical Museum had three Camm Moore compasses, he became extremely excited and requested images of them for study and comparison.

During our initial phone call and subsequent conversations, I realized that Jeff was extremely knowledgeable about Colonial instruments and, equally important, that he had many years of experience in metalworking and the cleaning and restoration of these pieces. I sent all three compasses to Jeff for closer examination and study, and ultimately for cleaning and repairs. We discussed the condition of each compass, including missing and non-original elements, prior repairs, and, in one case, damage to the original finish from over-cleaning. I appreciated Jeff’s thoughtful and candid approach to determining the appropriate level of treatment for each piece. The museum’s compasses now look terrific and I am especially pleased with the finish on the piece that had been previously damaged.

Without hesitation I would recommend Jeff Lock to other curators. His knowledge and skills are exceptional and his approach to restoration ranks among the highest ethical standards.”

Jon B. Zachman
Curator of Collections
Greensboro Historical Museum
Greensboro, North Carolina

“It was a stroke of pure luck that led me to Jeff Lock. Upon researching 18th century surveying instruments needed for a new exhibit, I came across Jeff’s website. I contacted him for a price inquiry, but never would I have imagined the unsurpassed aid he was about to provide!

Jeff took the time to discuss with me exactly what story we were trying to tell within our exhibit and helped to pinpoint the appropriate artifacts needed to fill that space. Due to his astounding wealth of knowledge on the subject, he was able to truly help us perfect our exhibit. He made recommendations for the good of the exhibit as a whole, which proved how much he cares for the visitor experience, as well. I have absolutely no doubt that the exhibit will be awe-inspiring, and all thanks will rest with Jeff.

The instruments, of course, were exceptional, and the experience of working with Jeff is not to be forgotten. I am extremely grateful for his kind words, attention to detail, extraordinary handicraft, and his unfathomable generosity. I greatly encourage anyone looking for 18th century surveying equipment, restoration, or even simply knowledge to please contact Jeff Lock. You absolutely will not regret a single moment of it.”

Jennifer Wildes
Museum Coordinator
Discovery Park of America
Union City, Tennessee


Before and After of the X-Y leveling head of the David Rittenhouse Precision Level in the Museum’s collection.

“Jeff Lock came to the Historical Society of Montgomery County to remove polishing compound residue from our David Rittenhouse precision level. Not only did he accomplish this task (with minimal change to patina), he also reattached a loose gear and made the telescope functional for the first time in years. When working with Jeff, one learns so much, not only about the instruments, but also about the craftsmen who made them. He understands the techniques used in their construction, and that gives him an insight into how and why the instruments were made the way they were. It also allows him to be very accurate in his treatments. It’s easy to see how passionate Jeff is about these instruments; it shows both in his personality and the quality of his work. We are very grateful for Jeff and pleased with the outcome of the treatment.” Read more about this project here.

Susan Pavlik
Historical Society of Montgomery County