Philip, who also holds the title Duke of Edinburgh, has been an honorary fellow of the society since 1951. He made mention of that in his impromptu remarks.
"It's now quite a long list since I've been doing this," he said referring to medal winners. "But it's a great pleasure to be back in circulation again."
Philip has spent the time since his hospitalization at the royal estate at Sandringham in Norfolk. He is joining his wife, Queen Elizabeth II, for their annual break at Balmoral in the Scottish Highlands.
He had enough energy for a joke as he presented medals to Sir John Cadogan, an organic chemist, Michael Ferguson, a molecular biologist at the University of Dundee, and Sir Ian Wood, a retired oil executive: "I wish to God I could understand what they'd been doing!"
Philip also presented the James Clerk Maxwell Medal to two U.S. pioneers in microelectro-mechanical systems technology, Richard Muller and Richard White of the University of California.
The prince cut back on his public schedule when he turned 90, although he still performs many engagements on his own and with the queen.
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