A list of patents for each county can be found in the Plats & Surveys (Plats.net) section on the Maryland State Archives website. Access to the list is the same for each county. Select the county from the drop down menu and go to the Tract Index line and click onto S1590 which is for Frederick County. A alphabetical listing of tract names will appear. The list is for the patent books the tracts are located. This list may differ from the Certificate of Survey listing.
Note: Tracts are missing and some don’t belong in the county your viewing. Verify the tract actually belongs in the listed county to insure accuracy.