page_title: Sherlock Holmes
section_title: Forensic science
hierarchical_section_title: Sherlock Holmes / Knowledge and skills / Forensic science
caption_attribution_description: Microscope from the late 19th century, manufactured by the optical firm W &amp; H Seibert in Wetzlar
context_page_description: Sherlock Holmes is a fictional private detective created by British author Sir Arthur Conan Doyle. Referring to himself as a "consulting detective" in the stories, Holmes is known for his proficiency with observation, deduction, forensic science, and logical reasoning that borders on the fantastic, which he employs when investigating cases for a wide variety of clients, including Scotland Yard.
  First appearing in print in 1887's A Study in Scarlet, the character's popularity became widespread with the first series of short stories in The Strand Magazine, beginning with "A Scandal in Bohemia" in 1891; additional tales appeared from then until 1927, eventually totalling four novels and 56 short stories. All but one are set in the Victorian or Edwardian eras, between about 1880 and 1914. Most are narrated by the character of Holmes's friend and biographer Dr. John H. Watson, who usually accompanies Holmes during his investigations and often shares quarters with him at the address of 221B Baker Street, London, where many of the stories begin.
  Though not the first fictional detective, Sherlock Holmes is arguably the best known.
context_section_description: Though Holmes is famed for his reasoning capabilities, his investigative technique relies heavily on the acquisition of hard evidence. Many of the techniques he employs in the stories were at the time in their infancy.
  The detective is particularly skilled in the analysis of trace evidence and other physical evidence, including latent prints (such as footprints, hoof prints, and shoe and tire impressions) to identify actions at a crime scene; using tobacco ashes and cigarette butts to identify criminals; handwriting analysis and graphology; comparing typewritten letters to expose a fraud; using gunpowder residue to expose two murderers; and analyzing small pieces of human remains to expose two murders.
  Because of the small scale of much of his evidence, the detective often uses a magnifying glass at the scene and an optical microscope at his Baker Street lodgings. He uses analytical chemistry for blood residue analysis and toxicology to detect poisons; Holmes's home chemistry laboratory is mentioned in "The Naval Treaty". Ballistics feature in "The Adventure of the Empty House" when spent bullets are recovered to be matched with a suspected murder weapon, a practice which became regular police procedure only some fifteen years after the story was published.
  Laura J. Snyder has examined Holmes's methods in the context of mid- to late-19th-century criminology, demonstrating that, while sometimes in advance of what official investigative departments were formally using at the time, they were based upon existing methods and techniques. For example, fingerprints were proposed to be distinct in Conan Doyle's day, and while Holmes used a thumbprint to solve a crime in "The Adventure of the Norwood Builder" (generally held to be set in 1895), the story was published in 1903, two years after Scotland Yard's fingerprint bureau opened. Nonetheless, Holmes inspired future generations of forensic scientists to think scientifically and analytically.
caption: 19th-century Seibert microscope
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