Fisher Silversmiths Bowl with Sterling Silver Base

Found this at GW last night hidden on an upper shelf. The silver caught my eye, but I was prepared to be disappointed by a plated piece. Wonder of wonders, I flipped it over and found the Sterling mark with hallmarks(last pic). Bowl is 12" across, and sits 3 1/2" high on the base. Base is 1 3/16" high and 5" in diameter at the base. There is also a #216 stamped into the base. This was obviously taken care of for a long time by someone who polished their silver regularly(there is a heavy layer of paste polish stuck in the grooves of the base. I know absolutely nothing about silver hallmarks. Can anyone give me a hand with an ID?