Roman Scales and some other stuff

I have been reading about Roman scales. I want to know more about how the Romans paid their soldiers at Veii. The first time Roman soldiers were paid was about 400 BC, or about 100 years before they started producing coins. Romans used two types of scales: balances with mirror image sides and steelyard scales with sliding weights and uneven sides. Some interesting pictures of scales are shown on pottery and funeral carvings. (See https://funtofil.livejournal.com/18042.html and others.)

This butcher shop has a steelyard scale.

This shop has a double pan balance.

The baked loaves are checked for weight at top.

A steelyard scale weighing cotton near Hico, Texas. Photo is not dated, but I guess it is from the first half of the 20th dentury. I saw a similar scale in the James Stewart movie "The Stratton Story". 

I found the following picture on the Library of Congress web site. Note the picture was copyrighted by Underwood and Underwood in 1897. The pic shows Steelyard scales and balance scales found at Pompeii. They were in the National Museum, Naples, Italy, room of small bronzes. I could not find a similar pic on their web site.

I have shown this scale before, but I have been researching how it worked. I suspect the parts were not used together.