Complex sentence: The psychical researcher Eric Dingwall observed Reese in New York and claimed to have discovered his cheating methods; according to Dingwall the exploits of Reese were "not worth any serious scientific consideration" and that Reese came into contact with the sealed notes.
Split into simpler sentences: The psychical researcher Eric Dingwall who observed Reese in New York claimed to have discovered his cheating methods. According to Dingwall the exploits of Reese were "not worth any serious scientific consideration" and Reese came into contact with the sealed notes.