The original poster may be long gone, but I thought I might make some comments to any late-comers that, like me, wander into this post. This knife does, indeed, appear to be made by Gorham. Like many American silversmiths, Gorham often stamped what are called faux hallmarks--hallmarks which mimic those used by British silversmiths--probably because it gave a patina of British quality to their products. But the "G" in the third position indicates the Gorham maker's mark.
This is a fruit knife, which was an item upper class ladies and gentlemen carried with them to picnics or dinner parties for the specific purpose of being used to cut fruit served. Early manners dictated that the proper way to eat fruit was not to handle it but to cut it into manageable slices before eating. The blades were usually made of silver, "coin" silver (900/1000) prior to 1864 or so, then more often sterling (925/1000) silver. Silver was used in the blade because it did not get corroded by acidic fruit juices.
A pen knife was another knife with a specific purpose. In the days before ballpoints or fountain pens, people most commonly used quills taken from the feathers of geese, ducks or other birds. The pen knife was a small knife with one or more small but sharp blades that were used to carve or re-carve points to the quill so that it could be dipped in an inkwell and used to write.