A Study In Scarlet is certainly a tale of violence and transgression. This story introduces the world to Arthur Conan Doyle's enigmatic sleuth, Sherlock Holmes, at once a pioneer of innovative, investigative techniques as well as a romantic figure of mystery and suspense.
Doyle wrote his story in 1886 and published it in 1887. In the late 19th century, London was a dangerous place. The typical Londoner lived in fear of kidnappings, muggings, and theft; the people had little, if any, faith in the efficacy of the Metropolitan Police Force. In 1888, the Jack The Ripper murders further terrified the populace, even while it captured the lurid imaginations of crime enthusiasts. The fact that the killer was never brought to justice gave the public little confidence that their lives would be secure from various and sundry threats. This was exactly why Doyle's Holmes became extremely popular.
Through his unorthodox methods of rational analysis and deductive reasoning, Holmes forever revolutionized a new type of forensic science, heretofore unknown to members of his profession. The English public delighted in their new, literary hero. Holmes gave the common man comfort that the police incompetence of their day would not be accorded the last say in criminal investigations. Holmes was presumably the first to use the science of ballistics, chemical analysis of poisons, and blood spatter analysis. The first, real forensics lab was built in 1910, 23 years affter Arthur Conan Doyle introduced us to Holmes' lab.
So, A Study In Scarlet wasn't largely concerned with just violence and transgression, it also explored how the perpetrators of these acts of violence could be brought to justice.
Aside from this, Doyle also explored the question of guilt. For example, was a person who committed murder always a criminal? In the story, Doyle investigated the criminal act as an instrument of justice. Part Two of the story delineated the background of both Jefferson Hope (the murderer of Enoch Drebber and Joseph Stangerson) and Lucy Ferrier. While Lucy was the quintessential 19th century heroine, as beautiful as she was good, Hope personified the typical American in his accessibility, individualism, and resourcefulness, traits that any working-class Englishman could relate to.
When his fiance died of a broken heart at being forced to marry against her will, Hope hunted down the perpetrators and gained justice for his beloved. Was this an act of vigilantism? Perhaps. However, the English populace lapped up the story. Doyle also explored the concept of the oppressed turned oppressor in Part Two, when the Latter Day Saint's Council of Four pronounced Lucy Ferrier's fate as irrevocable.
Doyle's inimical portrayal of a capable, new type of detective, juxtaposed with the idea that justice could manifest itself in unexpected ways, fueled the imaginations of the English populace in the 19th century. The topic of violence and transgression was never the same again with the advent of the inimitable Sherlock Holmes.
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