http://www.scales-and-weights.com/scales/scaleidx.htmThough USA-located, this website is clearly not written by a native English speaker, but it is nevertheless well constructed and very useful.
SPECIAL FEATURESClicking on Enter, you now have to select a scales type from a short menu on the left of the page, either
Antiquity, Opium, Coin, Commercial, Pharmacy or
Letter. Your choice may produce a secondary menu, subdividing the scales types again, but eventually you will be offered a selection of illustrations in the right-hand margin, from which you scroll down to select whichever is nearest to your particular query. You now need to use the internal scroll bar to the left of this margin to view the enlarged image in full, along with its description below.
Note that if you want to return to an earlier page, using the Back button at the top of your screen will only move what appears in the central section of your screen. You will need to use the Back command at the top of the menu if you wish to return to the original options.
Links, found at the extreme right of the header bar, is very well worth your time. The actual connections are in the pictures alongside each website description.
A good website with plenty of information and excellent links. 
