In the story, Otis Gardiner is a Coram man. Although he is supposedly affiliated with Coram Hospital, Captain Coram's foundling home, Otis is actually a perverted opportunist. He takes in the illegitimate offspring of poor and rich female patrons for profit. At considerable financial expense, each mother entrusts Otis with her child in the hopes that he will deliver it safely to Coram Hospital.
However, what Otis actually does is to sell the children into military service or slavery. Infants who cannot travel long distances are simply murdered. Often, defenseless babies are buried alive, and Meshak (Otis' mentally disabled son) hears their whimpering cries in his dreams. In the meantime, Otis continues earning residual income from grieving mothers who are none the wiser regarding his trade.
In this engaging novel, Meshak's story intersects with that of the wealthy Ashbrook family. Alexander Ashbrook is heir to the sumptuous Ashbrook estate. As a gifted singer and harpsichordist, Alexander nurses a secret desire to be a composer. However, Alexander's autocratic father insists on him relinquishing his musical ambitions for the sake of the Ashbrook estate.
In the midst of this domestic conflict, Alexander falls in love with Melissa Milcote, the governess' daughter. Meanwhile, Mrs. Lynch, an Ashbrook employee, notices Alexander's romantic inclinations towards Melissa. Mrs. Lynch is significant at this point in the story because she works closely with Otis Gardiner (the Coram man) in his trade. When Melissa becomes pregnant with Alexander's child, it is Mrs. Lynch who alerts Otis Gardiner to potential business at the Ashbrook estate.
With Alexander away to pursue his musical ambitions, Melissa has no choice but to give up the baby. However, Meshak (thoroughly sickened by his father's crimes) saves the baby, Aaron, from certain death. He takes Aaron to the Coram Hospital. While Aaron ends up being sponsored by Mr. Aaron Dangerfield (a cabinet maker), Meshak earns his keep at Coram by working in the fields.
In due time, like his father Alexander, Aaron displays his gift for music. As fate would have it, Aaron is apprenticed to Mr. Burney and Alexander Ashbrook (now a musician in his own right). It is Alexander who teaches his own son the elements of notation and harmony. He also teaches Aaron how to play the harpsichord; yet, both are oblivious to their biological connection until later. As events unfold, Alexander eventually discovers Aaron's identity after he reunites with Melissa.
In the meantime, Otis Gardiner is rumored to have been hanged for his horrendous crimes after his child-trafficking trade was discovered. Unknown to many however, Otis continues to profit from his evil trade as his alter ego, Phillip Gaddarn, a Coram Hospital philanthropist. Otis' eventual fate is ambiguous, but the novel ends on a positive note with Alexander and Aaron joyfully embracing their biological connection.
The eNotes article on Themes and Characters has a very good summary of the novel. I've pasted a link to it below.
Set in England during the mid 1700s, Coram Boy is the disturbing story of a man and his son who do an evil thing. Otis Gardiner and his son, Meshak, are peddlers; that is, they travel from town to town selling pots, pans, and other household goods. When the Coram Hospital, an orphanage in London, opens, Otis finds another source of income. For a fee, he claims to take the children that mothers can no longer care for or that were born illegitimately to the hospital. However, he sells the older children into slavery and makes his son bury the babies alive.
Although his father thinks he is simpleminded and has no remorse for what he has done, Meshak can't sleep for guilt. When Alexander Ashbrook and Melissa Milcote fall in love and have a son, Melissa's mother tells them that the baby died, but she secretly gives him to Otis. This time, however, Meshak decides not to kill the child. He believes that Melissa is the angel he keeps seeing in his dreams, so he decides to protect her child. The baby is named Aaron, and Meshak watches over him and Toby, a young African boy whom Otis had planned to sell.
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