Simplify the following text for a Grade 10 native English-speaking person.
Original: Other Lancashire magistrates learned of Nowell 's discovery of witchcraft in the county , and on 15 April 1612 JP Robert Holden began investigations in his own area of Samlesbury .
Simplified: Other Lancashire magistrates learned of Nowell 's discovery of witchcraft in the county . On 15 April 1612 JP Robert Holden began investigations in his own area of Samlesbury .