I recently received this inquiry:
"dug up bottles on property, about 40 clear glass but want to know what this duraglas small bottle with a roman numeral which looks like a 3 followed by an IV. It has mesurments on the side black lid with dark liquid still in it. Also an 'Old Quaker' half pint glass bottle with lid. Just want to know what these are. Thank you much for any help."
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It's a common enough bottle that it merits a response to help others.
The 3iv designation is a pharmacist's terminology for 4 ounces. If you really want to dig into this issue, then roll up your sleeves and get ready to digest the somewhat confusing notion that this is a matter of the relation between weight and volume of an ounce. The way I understand it, such a bottle would contain 4 ounces by weight and not by volume. See Pharmaceutical compounding and dispensing
By John F. Marriott for more information.
Such pharmacy bottles were mass-produced by a bottle manufacturer and sold to pharmacies. The local pharmacy applied their own label when filling a prescription. Today, the containers in some cases look similar but most are made of plastic. The Duraglas marking indicates that the bottle was made by Owens-Illinois Glass Company of Toledo, Ohio. The Duraglas trademark (in script) was used starting in 1940 and in bold blocked letters starting in 1963 - this information is from Bottle Makers and Their Marks by Julian Toulouse.
I will post a photo of representative examples
