1890 AH Fine Engraving - How did they do this?

[Big Friend Ten (BFT)]

I need to thin out the gun safe and I had thought about parting with this AH which was made in 1890. I mounted the trusty Nikon with a 60mm Micro lens on a tripod and got to work. The photos produced proved to me the err in my thinking. I decided that I had better keep this Parker.

I thought that I’d share with my distant Parker brothers why this is one to hang on to. Take a look at the fine engraving. Some of these dogs are less than 1/8 inch in height! How did anyone engrave subjects that small?

Let's start on the left side of the receiver,