Every medievalist should own a magnifying glass, even if he has perfect vision. Many medieval manuscripts were sometimes produced with the aid of magnifying glasses, so magnifying glasses are often required to study them. Then, there’s OED microprinting.
Lightwedge Bar Magnifier
The Lightwedge Bar Magnifier is most useful for reading microprinting. It sits on the page and has less magnifying power than handheld devices, but since it does not have to be held, it leaves one’s hands free for taking notes. This magnifier is only 3 cm wide, so you can imagine how small the text is in the picture (note: I intended to focus on the prefix “cyng-.” That “cynical” is magnified in the picture is a coincidence, not a statement). The purple line is for lining the magnifier up with the text, but I only find it useful on right-hand pages. Lightwedge and other companies make dome magnifiers (link to Amazon) that sit on the page like the bar magnifier. The dome design offers more magnifying power and is preferred by my friends who have vision problems, but they are not as effective for microprinted books since they often do not magnify an entire line at once. My Lightwedge was purchased for me at Barnes and Noble (thanks, Mom!) and should be easily available at office stores.
This magnifying glass, which I found is extremely difficult to photograph, came with my OED. It’s not unique in any way and dozens of rectangular magnifiers are cheaply availible (link to Amazon)at office stores. I like this magnifier because its rectangular shape fits well with the OED’s columns, but it has a big enough area that it’s still useful for examining carpet pages. (The book in the photograph is The Book of Kells by Charles Gidley.)
Pretty Magnifying Glass
This review will probably be relevant only to female medievalists. I love this glass because it’s pretty. This magnifier is tiny—a little less than 4 cm—but it looks nice and the chain means that I won’t lose it under a book when I put it down. It’s good for quickly looking at things that don’t need to be quoted, and it’s pretty. That’s all I need, really.
Choose a magnifier that’s right for you. It can be a cheap plastic thing, an antique brass reproduction, or a Sherlock Holmes-approved movie prop replica—whatever you like best as long as it makes text bigger. It doesn’t hurt if your magnifier of choice looks impressive on your desk, too.