"This series covers the period from the American Revolution to the mid-1800s. It includes a wide range of documents relating to the British Army in Canada, Loyalist regiments, the War of 1812, the Canadian militia, etc. A nominal/subject card index and the actual records are available on microfilm. References located in the index provide a brief description of the document, date, C Series volume number and a page number. After consulting the index, refer to the list of microfilm reel numbers for the actual records."On the third floor at the Library and Archives Canada building at 395 Wellington Street in Ottawa there is a set of wooden card catalogue boxes containing the index cards for the RG 8, C Series microfilms. These cards have also been digitized and placed online under "British Military and Naval Records (RG 8, C Series) - INDEX ONLY". I will be the first to admit that I find the online index to be time consuming to use and not as easy as flipping through the paper cards. But they are accessible to everyone without having to physically visit LAC.
However, before you start using this collection I would strongly recommend that you read the Help Page that Library and Archives Canada provides on searching this collection. The key index on that page is the breakdown of what names and regiments are on which microfilms that hold the index cards.
Here is a sample of one of those digitized index cards:
On the card is the person's name, a description of what the microfilmed document contains, a "C" number and a page number or two. In this case, the card points to volume 169 pages 139 and 143.
On problem is that the "C" number on the index card doesn't refer to the microfilm "C" collection. (Confused? So was I for a long time.) So the challenge is going from the "C" volume number on the index card to finding the document on the correct the "C" microfilm. To do that you need to go to the "RG 8, C Series: Microfilm Reel Numbers for Records (arranged by volume number)" page [NOTE: Due to a bad link on the LAC web site you can find this page archived by the Wayback machine at http://web.archive.org/web/20140331103002/http://www.collectionscanada.gc.ca/genealogy/022-909.002.07-e.html]. In this case, after looking through the page, I see that volume 169 is on microfilm C-2774.
Now you need to get to "British Military and Naval Records (RG 8, C Series) - DOCUMENTS" page so you can view the right microfilm. Finally you jump around the C-2774 digitized images of the microfilm until you find volume 169 and pages 139 and 143 in that volume. Fortunately at the bottom of the microfilmed images you will normally find the volume number. Most of the microfilms have multiple volumes records on them so it may take a bit of work to get to the right part of the microfilm. Additionally, the page number is often written in the top corner of the page.
Here is the image from the digitized microfilms that the index card referenced:
The best part about the digitized images is that they are normally of superior quality to the microfilms found on the open access stacks at Library and Archives Canada. In total it took me about 5 minutes of work to locate the microfilm, volume and specific page. Since I live so close to the Library and Archives Canada building in Ottawa I still find it easier to use the physical card catalogue when browsing and then I go online to view the document. But for those that don't live in Ottawa, this collection is a wonderful source if you have an ancestor that served in Canada prior to Confederation.