Here are the esentials:Moshe son of Gershon, 65 years of agedied in good name 24 Nisan 5699
Just to expand on what David said: The stone has an acrostic poem spelling out the name of the deceased. It doesn't have any specific genealogical information on it (these poems rarely do) other than saying that he was 65 years old and a very nice person.
If we take the poetic epitaph literally, your great-uncle died suddenly, in the prime of life, & was respected for his charity & his honesty in business & in public affairs.
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