Does anyone here know how to decipher them?
I bought the Longrow 10 referenced in the "Longrow 10" thread below. From what I've been able to find out, it must be a non-vintage Longrow 10 released before the vintage versions (which began with the '92?), which dates it to around 1991/2001. It's been suggested that its lime green label and capsule must have faded from their original brown, but that doesn't seem likely looking at them, as both match perfectly, and the capsule is uniform in color all around while the back label is distinctly brown.... I failed to mention last time around that it's in a taller bottle than the current. Maybe I'll try posting pics eventually.
Anyway, the only markings on the bottle I could find are on the bottom. In the very center of the circle, below the bottle-size statement running in a crescent along the border up top, is SD522, and in running a crescent along the bottom border below that, 419 [UG] U8. (The "UG" is boxed, thus the brackets; the "U" of "U8" looks too wide to be the litter U.)