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Guy Ritchie directed the second installment in what looks to be a series of Sherlock Holmes films starring Robert Downey, Jr., as Sherlock and Jude Law as Dr. John Watson. I reviewed the first when it came out in 2009, and the second, A Game of Shadows, is in much the same vein, with the excellent on-screen chemistry between Downey and Law making the film work. The latest film is set in 1891, and Holmes believes Professor James Moriarty (played by Jared Harris) is responsible for several notorious crimes across Europe, even though the press linked them to anarchists. Moriarty also appears to be acquiring controlling interest in a number of businesses, including gun manufacturers and bandage makers. Moriarty is above suspicion because of his reputation as a mathematical genius and acquaintance of the British prime minister. At the same time, Watson returns to Baker Street after a long absence to get Holmes to attend his (Watson’s) wedding to Mary (an event foretold at the end of the first film). The newlyweds are attacked on a train as they leave for their honeymoon, but Holmes is there to protect them. This begins a chase across Europe that encompasses London, France, and northern Germany, and ends in Switzerland at an international peace conference. Those familiar with the original stories by Sir Arthur Conan Doyle will likely predict how the film ends.
A Game of Shadows gives teachers a chance to discuss chemical safety, transportation technology, and mathematics near the turn of the 20th century.
The great detective in disguise on a train in Sherlock Holmes: A Game of Shadows
When Watson arrives at Baker Street near the beginning of the film, Holmes is in terrible shape: He is unshaven and unkempt, and appears to be under the influence of a drug. The housekeeper mentions Holmes has been chewing coca leaves (a way to ingest the stimulant cocaine). Watson also implies that Holmes has been drinking formaldehyde, and we see a bottle labeled as such on the table. Formaldehyde (chemical formula CH2O) is a gas at room temperature, but is frequently used in a saturated water solution known as formalin. Formalin, which contains 37% formaldehyde by mass with some methanol to help stabilize the solution, was commonly used as a disinfectant and to preserve tissue samples. Due to the long-term carcinogenic effects of formaldehyde, these practices are no longer considered safe. In the short term, however, drinking as little as an ounce (30 mL) of formalin can be fatal to an adult, so the likelihood of Holmes surviving drinking much of it would be very small. Small doses are known to have significant effects, including headache, vertigo, and stupor. One of the most important components of chemical lab safety is preventing the accidental ingestion of substances like formalin. (Visit NSTA’s Safety Portal for more information on safety in the science classroom.)
While Ritchie’s first Holmes film emphasized construction themes (with the final battle atop the incomplete Tower Bridge in London), transportation at the end of the 19th century is the emphasis here. In Game of Shadows, Holmes and Watson travel by horseback, carriage, train, side paddle wheel steamship, and automobile, while in the background we see part of the London Underground being built in the middle of Baker Street. All of these modes of transport were used in the 1890s, with horseback, carriage, and train all very popular. The film might overestimate the availability of a four-wheeled automobile in London in 1891, as no cars were being built in England at that time, and most of the German cars before 1894 were three-wheelers. I was impressed by the sea-going side paddle wheel steamship Holmes and Watson use to cross the English Channel. Americans are most familiar with paddle wheel boats as the Mississippi riverboats made famous by Mark Twain, but paddle wheel steamers also were built for sea voyages.
The difficulty of getting from England to France across the Channel has largely been mitigated by the Channel Tunnel, or Chunnel, which opened in 1994. The idea of a tunnel under the English Channel is not a new one, though. A French engineer proposed a tunnel in 1802, and the idea was revisited several times throughout the 19th century. The modern tunnel carries only trains, although auto traffic is carried on special train cars, making it ipossible to drive from London to Paris in about six hours.
Finally, a nice tidbit for math teachers appears on a blackboard behind Moriarty when Holmes visits his quarry. The board is filled with notations, but prominent in the center is a copy of Pascal’s Triangle, the first six rows of which are shown below. The rows are constructed by adding adjacent numbers in the row above. For example, in row four, the 3s are the sum of the 1 and 2 in row three. This arrangement shows the coefficients in a binomial expansion. So, for example, (x + y)2 = 1x2 + 2xy + 1y2 and (x + y)3 = 1x3 +3x2y + 3xy2 + 1y3.
The triangle contains a number of other patterns that can be useful to mathematicians, but I will leave those as a discovery exercise for readers. As a mathematical genius, Moriarty would not have needed to keep this written down on his blackboard. Perhaps he had just been working with an undergraduate during office hours?
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1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
The latest Sherlock Holmes adventure, A Game of Shadows, has potential for classroom connections in chemistry and mathematics, and can spark a conversation about transportation technology before the turn of the 20th century.
Jacob Clark Blickenstaff is teacher education programs manager for the American Physical Society. He can be reached at blickenstaff@aps.org.
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