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Photo, Print, Drawing Chesapeake & Ohio Canal, Big Slackwater Towpath, McMahon's Mill to Lock 42, Milepost 88.10 to Milepost 89.04, Williamsport, Washington County, MD Chesapeake & Ohio Canal National Historical Park

[ Data Pages from Survey HAER MD-193  ]

More Resources

[ Photo Captions from Survey HAER MD-193  ]

About this Item

Title

  • Chesapeake & Ohio Canal, Big Slackwater Towpath, McMahon's Mill to Lock 42, Milepost 88.10 to Milepost 89.04, Williamsport, Washington County, MD

Other Title

  • Chesapeake & Ohio Canal National Historical Park

Names

  • Historic American Engineering Record, creator
  • Chesapeake & Ohio Canal Company
  • Purcell, Thomas F.
  • Fisk, Charles B.
  • Grove, John D.
  • Holman, Joseph
  • Byrne, Michael
  • Cochran, Matthew, historian
  • Berg, David C., photographer
  • The Ottery Group, contractor
  • U.S. National Park Service (NPS), sponsor
  • McPartland, Mary, transmitter

Created / Published

  • Documentation compiled after 1968

Headings

  • -  canals
  • -  transportation
  • -  locks (hydraulic facilities)
  • -  towpaths
  • -  stone retaining walls
  • -  culverts
  • -  concrete bridges
  • -  limestone
  • -  Maryland--Washington County--Williamsport

Latitude / Longitude

  • 39.53025,-77.82439

Notes

  • -  Significance: The Chesapeake & Ohio (C&O) Canal, Big Slackwater Towpath, McMahon's Mill to Lock 42, is a significant example of an engineered nineteenth century waterway in the Potomac Valley and Western Maryland, used for commercial transportation purposes. The section of the C&O Canal between McMahon's Mill and Lock 41 is unique in that it is one of only two places along the canal where boats were deliberately navigated out of the engineered canal prism and into the Potomac River owing to the desire to avoid the costly endeavor of cutting a prism through the existing terrain. Between Locks 41 and 42, boats still navigated through the artificial canal prism. However, they were towed from the berm, or landward, side of the prism and not the typical river-side since slackwater navigation required transitioning the mules over the engineered waterway via a crossover bridge, once located at the lower end of Lock 42. The canal towpath, between McMahon's Mill and Lock 41 is located adjacent to steep limestone cliffs that evidence both the towpath's construction c. 1836, as well as its continued use throughout the later part of the nineteenth and early twentieth century.
  • -  Survey number: HAER MD-193
  • -  Building/structure dates: ca. 1836- ca. 1839 Initial Construction
  • -  Building/structure dates: ca. 1970 Subsequent Work
  • -  National Register of Historic Places NRIS Number: 66000036

Medium

  • Photo(s): 39
  • Data Page(s): 64
  • Photo Caption Page(s): 9

Call Number/Physical Location

  • HAER MD-193

Source Collection

  • Historic American Engineering Record (Library of Congress)

Repository

Control Number

  • md2202

Rights Advisory

Online Format

  • image
  • pdf

Rights & Access

The Library of Congress does not own rights to material in its collections. Therefore, it does not license or charge permission fees for use of such material and cannot grant or deny permission to publish or otherwise distribute the material.

Ultimately, it is the researcher's obligation to assess copyright or other use restrictions and obtain permission from third parties when necessary before publishing or otherwise distributing materials found in the Library's collections.

For information about reproducing, publishing, and citing material from this collection, as well as access to the original items, see: Historic American Buildings Survey/Historic American Engineering Record/Historic American Landscape Survey (HABS/HAER/HALS) Collection - Rights and Restrictions Information

Obtaining Copies

If Digital Images Are Displaying

You can download online images yourself. Alternatively, you can purchase copies of various types through Library of Congress Duplication Services.

HABS/HAER/HALS materials have generally been scanned at high resolution that is suitable for most publication purposes (see Digitizing the Collection for further details about the digital images).

  • Photographs--All photographs are printed from digital files to preserve the fragile originals.
    • Make note of the Call Number and Item Number that appear under the photograph in the multiple-image display (e.g., HAER, NY,52-BRIG,4-2).
    • If possible, include a printout of the photograph.
  • Drawings--All drawings are printed from digital files to preserve the fragile originals.
    • Make note of the Survey Number (e.g., HAER NY - 143) and Sheet Number (e.g., "Sheet 1 of 4"), which appear on the edge of the drawing. (NOTE: These numbers are visible in the Tiff "Reference Image" display.)
    • If possible, include a printout of the drawing.
  • Data Pages
    • Make note of the Call Number in the catalog record.

If Digital Images Are Not Displaying

In the rare case that a digital image for HABS/HAER/HALS documentation is not displaying online, select images for reproduction through one of these methods:

  • Visit the Prints & Photographs Reading Room and request to view the group (general information about service in the reading room is available at: https://aj.sunback.homes/rr/print/info/001_ref.html). It is best to contact reference staff in advance (see: https://aj.sunback.homes/rr/print/address.html) to make sure the material is on site. OR
  • P&P reading room staff can provide up to 15 quick copies of items per calendar year (many original items in the holdings are too old or fragile to make such copies, but generally HABS/HAER/HALS materials are in good enough condition to be placed on photocopy machines). For assistance, see our Ask a Librarian page OR
  • Hire a freelance researcher to do further selection for you (a list of researchers in available at: https://aj.sunback.homes/rr/print/resource/013_pic.html).
  • You can purchase copies of various types, including quick copies, through Library of Congress Duplication Services (price lists, contact information, and order forms for Library of Congress Duplication Services are available on the Duplication Services Web site):
    • Make note of the Call Number listed above.
    • Look at the Medium field above. If it lists more than one item:
      • The entire group can be ordered as photocopies or high-quality copies.
      • All the items in a particular medium (e.g., all drawings, all photographs) can be ordered as photocopies or high-quality copies.

Access to Originals

Please use the following steps to determine whether you need to fill out a call slip in the Prints and Photographs Reading Room to view the original item(s). In some cases, a surrogate (substitute image) is available, often in the form of a digital image, a copy print, or microfilm.

  1. Is the item digitized? (A thumbnail (small) image will be visible on the left.)

    • Yes, the item is digitized. Please use the digital image in preference to requesting the original. All images can be viewed at a large size when you are in any reading room at the Library of Congress. In some cases, only thumbnail (small) images are available when you are outside the Library of Congress because the item is rights restricted or has not been evaluated for rights restrictions.
      As a preservation measure, we generally do not serve an original item when a digital image is available. If you have a compelling reason to see the original, consult with a reference librarian. (Sometimes, the original is simply too fragile to serve. For example, glass and film photographic negatives are particularly subject to damage. They are also easier to see online where they are presented as positive images.)
    • No, the item is not digitized. Please go to #2.
  2. Do the Access Advisory or Call Number fields above indicate that a non-digital surrogate exists, such as microfilm or copy prints?

    • Yes, another surrogate exists. Reference staff can direct you to this surrogate.
    • No, another surrogate does not exist. Please go to #3.
  3. If you do not see a thumbnail image or a reference to another surrogate, please fill out a call slip in the Prints and Photographs Reading Room. In many cases, the originals can be served in a few minutes. Other materials require appointments for later the same day or in the future. Reference staff can advise you in both how to fill out a call slip and when the item can be served.

To contact Reference staff in the Prints and Photographs Reading Room, please use our Ask A Librarian service or call the reading room between 8:30 and 5:00 at 202-707-6394, and Press 3.

Cite This Item

Citations are generated automatically from bibliographic data as a convenience, and may not be complete or accurate.

Chicago citation style:

Historic American Engineering Record, Creator, Chesapeake & Ohio Canal Company, Thomas F Purcell, Charles B Fisk, John D Grove, Joseph Holman, Michael Byrne, Matthew Cochran, Contractor The Ottery Group, and Sponsor U.S. National Park Service, Berg, David C, photographer. Chesapeake & Ohio Canal, Big Slackwater Towpath, McMahon's Mill to Lock 42, Milepost 88.10 to Milepost 89.04, Williamsport, Washington County, MD. Williamsport Maryland Washington County, 1968. translateds by Mcpartland, Marymitter Documentation Compiled After. Photograph. https://aj.sunback.homes/item/md2202/.

APA citation style:

Historic American Engineering Record, C., Chesapeake & Ohio Canal Company, Purcell, T. F., Fisk, C. B., Grove, J. D., Holman, J. [...] U.S. National Park Service, S., Berg, D. C., photographer. (1968) Chesapeake & Ohio Canal, Big Slackwater Towpath, McMahon's Mill to Lock 42, Milepost 88.10 to Milepost 89.04, Williamsport, Washington County, MD. Williamsport Maryland Washington County, 1968. McPartland, M., trans Documentation Compiled After. [Photograph] Retrieved from the Library of Congress, https://aj.sunback.homes/item/md2202/.

MLA citation style:

Historic American Engineering Record, Creator, et al., photographer by Berg, David C. Chesapeake & Ohio Canal, Big Slackwater Towpath, McMahon's Mill to Lock 42, Milepost 88.10 to Milepost 89.04, Williamsport, Washington County, MD. trans by Mcpartland, Marymitter Documentation Compiled After. Photograph. Retrieved from the Library of Congress, <aj.sunback.homes/item/md2202/>.