8500
Futile attempts were made by Charles Babbage , Peter Barlow , John Herschel and others to explain this phenomenon .
 person: Charles Babbage; person: Peter Barlow; person: John Herschel
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
 Entities: Charles Babbage, Peter Barlow, John Herschel 
Answer:
 person: Charles Babbage; person: Peter Barlow; person: John Herschel