"The Adventure of the Engineer's Thumb" is a Sherlock Holmes short story by the British author Sir Arthur Conan Doyle. Its first appearance in print was in The Strand magazine in March 1892. It would be published again in October of that year as part of the anthology The Adventures of Sherlock Holmes.
In the story, Dr. John Watson treats a patient who has lost a thumb. The patient says that the loss of his thumb was not an accident but the result of an attack. However, he fears that the story behind the loss of his digit is so strange that the police will not believe it. Dr. Watson tells the man that he should first go to see his friend the brilliant consulting detective Sherlock Holmes.
"The Adventure of the Engineer's Thumb" has been adapted for American television and for television in the Soviet Union.
The action takes place in the summer of 1889. Dr. Watson has recently married. He no longer lives with his friend Sherlock Holmes in Baker Street but still sees him often. Dr. Watson has taken up a private medical practice again. His surgery is near to Paddington train station. A guard at the station often recommends patients to him.
One morning, the guard brings a patient to see Watson. The patient's business card declares him to be a hydraulic engineer called Victor Hatherley who has offices in Victoria Street, London. Victor Hatherley has one hand bandaged with a handkerchief. When he removes it, Watson sees that the man has lost one of his thumbs. Watson asks if it was lost in an accident. Victor Hatherley replies that it was not and that he was attacked. He knows that he will have to tell the police but he is afraid that they will not believe his story. Dr. Watson tells Hatherley that he should speak to Sherlock Holmes first. The two men go off to see Holmes together.
Victor Hatherley tells Holmes that he qualified as a hydraulic engineer and started his own business two years earlier. Business has not been good in those two years. Consequently, Hatherley was happy to receive a client the day before. The client was a tall thin man who spoke with a slight German accent and called himself Colonel Lysander Stark. The colonel offered Hatherley fifty guineas for about one hour's work. He told Hatherley that he would be required to analyze the problem with a hydraulic stamping machine. He would not be required to fix the machine because the colonel and his companions would be able to do that themselves after the problem was explained to them. He is told that he would be required to take the last train to the village of Eyrford in Berkshire. He would arrive at around 11:15pm and then be taken by carriage to the house where the machine was kept. He would arrive at the house at around midnight and be allowed to stay until the morning. The colonel insisted on Victor Hatherley keeping everything about the job secret. He told Hatherley that one reason why he chose him for the job was because he was not married, lived alone and had no family. The colonel said that makes him more likely to be able keep a secret than a family man.
When Victor Hatherley asked why there was the need for secrecy, the colonel gave the following explanation. He said that he had found the valuable mineral fuller's earth on his property. He later discovered that there was even more fuller's earth on land which belonged to his neighbors. He wanted to buy that land but, in order to keep the price low, he wanted to keep the reason for the purchase secret. He also did not have quite enough money to buy the land at its current value. A friend suggested that he should start secretly mining and selling the fuller's earth on his property in order to raise money. The hydraulic stamping machine was used to shape the fuller's earth into bricks in order to disguise it.
Victor Hatherley arrived at Eyrford station a little after eleven o'clock that evening. Colonel stark met him in a carriage. The carriage had frosted windows so that Hatherley could not see where he was going. After a journey of about an hour, during which hatherley believes he traveled ten miles, they arrived at a dimly lit house. A woman appeared who spoke to the colonel in a foreign language. The colonel said something to her which made her leave and made her appear frightened. Hatherley was told to wait in a room in which he saw some books in German. The woman reappeared. She told Hatherley in broken English that he was in danger and should leave immediately. She left when she heard footsteps. Colonel Stark returned with a short fat man. He said that the man was his manager and secretary Mr. Ferguson. Although he did not speak much, Hatherley could tell that Mr. Ferguson was English.
Hatherley was led upstairs and taken inside a room. The room's walls are made of wood but its ceiling is made of metal and its floor is a metal trough. Colonel Stark explained that the entire room was inside a gigantic hydraulic stamping machine. The room's metal ceiling was really the end of the descending piston. The colonel went on to say that the machine still worked but it seemed to be a bit stiff. Hatherley examined the machinery, identified the problem and told Colonel Stark and Ferguson how they could fix it.
Having noticed that the metal trough which was the room's floor was covered with a metallic powder which was certainly not fuller's earth, Hatherley decided to investigate it further with the aid of an oil lamp. Colonel Stark found him and asked what he was doing. Haterley replied that he would be able to help more if he knew what the machine was really being used to do. The colonel told Hatherley, "You should know all about the machine", slammed and locked the door and turned on the machine. The metal ceiling descended. Hatherley thought about how to position himself in order to make his death by crushing as painless as possible. Noticing again that the room's walls were made of wood, Hatherley was able to burst through a widening gap in one of them. He hears his oil lamp break after he escapes.
Finding himself in a corridor, Hatherley was met again by the woman. She led him to a bedroom window from which he could escape. While he was hanging by his hands from the windowsill, Hatherley saw Colonel Stark enter the room with a cleaver in his hand. Calling him Fritz, the woman said to Colonel Stark, "remember your promise after the last time. You said it should not be again". She tried to persuade him that Hatherley would not speak about his experiences in the house. However, the colonel pushed past her and struck at one of Hatherley's hands with the cleaver. Hatherley fell to the ground but was not hurt. While he was running away, he noticed that his thumb had been cut off by the colonel. he bandaged the wound with his handkerchief but fainted soon afterwards. When he came round, Hatherley found that it was morning. He was no longer in the grounds of the house but was instead near to Eyrford train station. he later says that he has a vague recollection of having been carried there. He went inside the station and began his journey back to London.
Sherlock Holmes shows Victor Hatherley a newspaper clipping from the previous year. It is about the disappearance of a hydraulic engineer called Jeremiah Hayling. Holmes believes that he was the last engineer to examine Colonel Stark's machine and was murdered afterwards. That explains what the woman was referring to when she spoke about "the last time".
Soon afterwards, Holmes, Watson, Victor Hatherley, Inspector Bradstreet of Scotland Yard and another police officer are traveling by train to Eyrford, Berkshire. Both Holmes and Inspector Bradstreet agree that the criminals they are looking for are forgers who used the hydraulic stamping machine to make counterfeit coins. Inspector Bradstreet is aware of counterfeiters operating near the Berkshire town of Reading. Since his journey by carriage the night before took about an hour, Victor Hatherley believes that he was taken about ten miles from the village of Eyrford. Inspector Bradstreet draws a circle showing a radius of ten miles around Eyrford on a map but does not know if they should start searching north, south, east or west of the village. Holmes says that they should not search in any of those directions but in the center of the circle instead. He believes that the house which Hatherley was taken to is near to Eyrford train station. He was taken away from the station for about thirty minutes and then back in the direction from which he came as a ruse to confuse him.
On arrival in Eyrford, the travelers find out that a house near the train station is on fire. It is the home of Dr. Becher, an overweight man who had a very thin foreigner staying with him. Hatherley recognizes it as the house he was taken to the night before. Holmes says that the fire was probably started when Hatherley's oil lamp was broken. Hatherley is told to look out for the three occupants of the house but cannot see them. Holmes and Watson later find out that they were seen leaving early that morning on a cart loaded with boxes. The counterfeiters are never seen again. The boxes which they took away on their cart presumably contained the counterfeit coins. No coins are found inside the house but large amounts of nickel and tin are. Firefighters are also shocked to find a human thumb on a windowsill.
"The Adventure of the Engineer's Thumb" was adapted as the ninth episode of Sherlock Holmes, an American TV series starring Ronald Howard as Holmes and Howard Marion Crawford as Watson. The episode, called "The Case of the Shoeless Engineer", first aired in the United States in syndication on January 3, 1955. As the episode's title indicates, Victor Hatherley does not have his thumb cut off by Colonel Stark but merely loses a shoe while being helped to escape from the hydraulic press by the woman. Also, unlike in the original short story, Colonel Stark is killed in the fire at the house. His accomplice (the equivalent to Ferguson, renamed Carew and made the woman's uncle) is found and arrested.
The Adventures of Sherlock Holmes and Dr. Watson - The Twentieth Century Approaches, a 1986 TV movie from the Soviet Union which stars Vasily Livanov as Holmes and Vitaly Solomin as Watson, is based on "The Adventure of the Engineer's Thumb". "The Adventure of the Second Stain", "The Adventure of the Bruce-Partington Plans" and "His Last Bow".
- Sound file of public domain audiobook of "The Adventure of the Engineer's Thumb" from LibriVox
- "The Adventure of the Greek Interpreter", another Sherlock Holmes story in which the client is taken to a dimly lit house in a secret location