particularly for morphine, had gained popularity following its introduction in the 1850s. While much scholarly attention has focused on the psychological and symbolic aspects of Holmes’s cocaine use, relatively little consideration is given to the economics of the habit. This is not an incidental matter. Understanding how much cocaine cost in the 1880s and 1890s provides further insight into Holmes’s social status, the accessibility of the drug, and the financial realities of maintaining such a practice. In Victorian Britain, cocaine hydrochloride was typically sold by chemists either in powdered form or as a prepared solution. By the late 1880s, cocaine was commercially available from firms such as Burroughs Wellcome & Co., who sold it in sealed glass ampoules for medical use. Prices varied depending on strength, purity, and supplier, but contemporary pharmaceutical catalogues provide a useful benchmark.
But what was the financial cost of the drug? In 1885, for example, the wholesale cost of cocaine hydrochloride was approximately 8 to 10 shillings per gram. A seven-percent solution—Holmes’s preferred formulation—would require approximately 0.07 grams per millilitre of liquid. A 10ml vial, suitable for several injections, would therefore contain 0.7 grams of cocaine and cost roughly 6 to 7 shillings, retail. To contextualise that sum, it is helpful to consider the Victorian value of money. In 1890, a skilled tradesman earned about 30 shillings per week, while a middle-class professional like Dr. Watson would earn somewhere between £300-500 from his practice. Holmes, who derived income from clients, published monographs, and occasional government work,also would not have found this cost prohibitive. Adjusted for inflation using the UK Retail Price Index, 7 shillings in 1890 equates to approximately £30 to £35 in today’s currency, or around $40 to $45 USD. This suggests that while not cheap, cocaine was well within reach for a man of Holmes’s financial means. Moreover, because the drug was unregulated, prices were driven more by demand and purity than by taxation or legal restriction. Holmes, who likely used the drug intermittently—during times of intellectual stagnation—would not have required vast quantities. A regular monthly supply may have cost no more than £1 to £2 in Victorian money, or roughly £150–£250 today, assuming moderate use. Moreover, the economic evidence aligns with the canonical portrait of Holmes as a financially independent bachelor with modest but sufficient means. His drug use, while concerning to Watson, would not have imposed a financial strain. It was, like his monographs on cigar ash or his custom-made disguises, another element of his privately curated professional life. The literary decision to make Holmes a cocaine user was unusual, though not without precedent. In the late 19th century, there was a strong cultural association between genius and melancholy, and between intellectual pursuit and psychological instability. The idea of the “tormented mind” had Romantic roots, and Doyle, though a man of science, understood that readers expected their heroes to be flawed. Holmes’s cocaine use humanises him. It exposes vulnerability. It establishes that despite his formidable logic, he is subject to the same emotional disquiet that afflicts ordinary men. Holmes’s greatest strength—his analytical mind—is also the source of his deepest distress. Without a mystery to solve, his gifts become burdens. Modern psychological models have attempted to explain Holmes’s behaviour in contemporary terms. Some scholars propose that he may display symptoms of a bipolar temperament: alternating periods of intense energy and depressive inertia. Others suggest autistic traits, citing his social detachment, emotional reserve, obsessive focus, and pattern-seeking behaviour. Still others see signs of clinical depression masked by compensatory hyperactivity. Whatever the framework applied, it is clear that Holmes’s drug use is not hedonistic. He takes cocaine not to numb pain or to chase pleasure, but to simulate the cognitive excitement he otherwise derives from work. If Holmes’s drug use reflects internal strain, Watson represents the counterbalancing force of external structure and care. From their first appearance together, Watson attempts to impose limits. He observes, monitors, and gently confronts. Holmes may mock his friend’s concern, but he rarely dismisses it entirely. Watson’s medical knowledge gives his advice weight, but it is his role as companion and moral centre that gives it impact. Over time, Watson’s influence appears to bear fruit. In The Adventure of the Missing Three-Quarter, published in 1904, Watson notes with satisfaction: “For years I had gradually weaned him from that drug mania which had threatened once to check his remarkable career.” The use of the term “weaned” implies a long process of reduction, guided not by force but by persistent encouragement and example. That the Canon never depicts a dramatic recovery scene suggests that Conan Doyle did not wish to moralise the issue. Holmes’s renunciation of cocaine is understated, like most of his personal development. The detective remains essentially unchanged in outward manner, but internally, something has shifted.