08.21.06
Great Website for Eyeglasses Research
I was contacted by the author of this site a few months ago and I have to say it has more antique eyewear info in one place than anything else I have run into. Super informative section on dating specific features of eyeglasses, but it can be a bit slim on giving the primary documentation on those specific features. You won’t find anything better about 18th century spectacles on the web.
http://www.antiquespectacles.com/