Seymour Smith was a Connecticut company, started in 1866 until they were bought by Vermont American in 1985.
These pruners are great. A bit finicky to restore ones with heavily damaged blades and anvils; they need to mate perfectly to cut properly.
I’ve read that anvil pruners are not the best things to use for cutting living plants, that they crush plant tissue instead of severing it. These for dead things, bypass pruners for live things.
Seymour Smith also made bypass pruners, here’s a catalog from 1920 showing the ones they made at that time. That “Telephone Pruner” looks excellent.
Here’s a site with all the information you will probably ever need about these tools.
Here’s a patent from 1951.