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which had been noticed by Humphry Davy in 1821 , Benjamin Silliman in 1822 , Auguste Arthur de la Rive in 1846 , and David Edward Hughes in 1878 .
 person: Humphry Davy; person: Benjamin Silliman; person: Auguste Arthur de la Rive; person: David Edward Hughes
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Humphry Davy, Benjamin Silliman, Auguste Arthur de la Rive, David Edward Hughes 
Answer:
 person: Humphry Davy; person: Benjamin Silliman; person: Auguste Arthur de la Rive; person: David Edward Hughes