What is "hypsicrates"

Hypsicrates the historian was a Greek writer in Rome who flourished in the 1st century BC. His work does not survive, but scholars have conjectures about the writer and his work. He was associated probably with Pontus and wrote a history of the area that was possibly used by Strabo. He may be the same Hypsicrates who served as a slave for Julius Caesar and was freed by Caesar in 47 BC.