9553
Sir Charles Wheatstone discovered its principle and applied it as early as 1838 to the construction of a cumbersome but effective instrument , in which the binocular pictures were made to combine by means of mirrors .
 person: Charles Wheatstone
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 person: Charles Wheatstone