It is accurate to describe Sherlock Holmes as a "scientific detective" because he often applies forensics to his investigations. Forensics are scientific tests or experiments used to identify a criminal. For instance, Holmes uses footprints in Sign of the Four to recognize that one of the culprits is a foreigner. Fingerprints, footprints, and chemical reactions can all be used in forensic science by scientific detectives to find a culprit. For these reasons, it is accurate to describe Holmes as a scientific detective.
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