The ones with screw on lids, late 1800s- early 1900s, in fruit jar or product jar referance books. The ones with pry off lids, 1890s to present will be found in referance books on drinking glasses.
HUFF...you talking about the small "bowl" looking jelly glasses? Some had a "Quilt" pattern and some were just slick sided with a rayed pattern on the base or plain bases...used a tin lid that slid over the mouth...and were re-usable...Most I have seen are machine made and date from the late 19-teens into the 40's.
You hit it right on the head. The slick sided ones were the ones I was really curious about. I found a whole case of them in my barn and the only way I could tell they were mason jars was because of the logo on the lid. I see a lot of the others but these were the first I've seen slick sided.