Tom Swift and His Submarine Boat

In Short

When Barton Swift and his teenage son Tom complete an advanced electrical submarine, they forgo a government competition to hunt for gold lost aboard the sunken vessel Boldero off the South American coast. Pursued by unscrupulous corporate rivals, delayed by bad weather, and arrested by a Brazilian warship, Tom, his father, and their eccentric allies rely on technical ingenuity to survive. First published in 1910 as part of Victor Appleton's classic series, the book remains a memorable juvenile adventure through its imaginative electric gadgetry, fast pace, and optimistic faith in scientific invention.

The Story

The story opens at the Swifts' coastal residence in New Jersey, where veteran inventor Barton Swift, his inventive son Tom, and balloonist Mr. Sharp finish constructing the Advance, a revolutionary submarine propelled by positive and negative electrical plates. Their work draws the attention of Mr. Berg, an agent for the rival engineering firm Bentley & Eagert. After Berg tries to probe their plans, Tom accidentally reveals that they are targeting a prize far larger than the fifty-thousand-dollar government contract Berg seeks. Soon after, Tom is briefly trapped inside the craft's airtight water-ballast tank by his old enemy, Andy Foger, though he is safely released when his companions return.

Determined to secure the treasure of the Boldero—a ship sunk off Uruguay carrying three hundred thousand dollars in gold bullion—the team hires Captain Alden Weston, a mild-mannered but tough soldier of fortune, to serve as navigator. Joined by the eccentric, oath-swearing Mr. Wakefield Damon, they launch the Advance and put her through successful trial runs, though an early dive leaves them temporarily stuck on the ocean floor when the ballast pumps jam.

Once underway for the South American coast, they find themselves pursued by the Wonder, a competing submarine operated by Berg’s associates. The rivals attempt to ram the Advance underwater, forcing Tom to defend the craft using an innovative electric cannon that fires solid iron shot without gunpowder.

Reaching tropical waters, the expedition faces a new threat when a Brazilian cruiser, the San Paulo, intercepts them near a remote island. The warship's commander accuses the Americans of trespassing and takes them prisoner. As a fierce hurricane strikes the island, Captain Weston, Tom, and the crew stage a daring break for freedom during the storm, overpowering the guards, swimming out to the Advance, and diving into the deep before the warship can fire.

Reaching the exact coordinates of the wreck, Tom and Captain Weston don heavy metal diving suits to explore the ocean floor. While working near the Boldero, they are ambushed by a giant shark. Tom slays the creature with a harpoon, but the blood attracts a frenzy of sea wolves. Barton Swift saves the divers by firing anti-personnel charges from the submarine's electric cannon. Using the Advance to ram open the shattered hull of the Boldero, the crew recovers the heavy gold bullion and returns home to Shopton, New York, where Tom deposits the treasure and rewards his loyal friend Ned Newton.

How It Unfolds

The secret plan Tom Swift and his father complete the electrical systems of the Advance while keeping their destination secret from corporate agent Mr. Berg. Shortly after, Tom's local rival, Andy Foger, sneaks into the construction shed and locks Tom inside an airtight ballast tank, though the young inventor is rescued before his air runs out.

Gathering the crew The Swifts recruit Captain Alden Weston, a mild-mannered veteran navigator, and welcome aboard their eccentric friend Mr. Wakefield Damon. During initial sea trials, the submarine successfully dives but becomes temporarily stranded on the ocean floor when the main water-ballast pumps fail to operate.

The race under the sea Upon setting sail for the South American coast, the crew discovers that Berg’s rival submarine, the Wonder, is tailing them. When the Wonder attempts to ram their hull underwater, Tom uses an experimental electric cannon to disable the hostile vessel and preserve their lead.

Captured by the navy After stopping near a tropical island for fresh water, the Advance is surrounded by the Brazilian warship San Paulo, whose crew arrests Tom and his companions. Taking advantage of a sudden tropical hurricane, the captives overpower their guards, swim to their craft, and submerge into safe waters.

Securing the gold At the wreck of the Boldero, Tom and Captain Weston explore the seabed in diving suits, narrowly escaping a violent shark attack through well-timed cannon fire from the submarine. After ramming the wrecked hull to gain entry, they haul the gold aboard and return to Shopton triumphant.

The People

• Tom Swift wants to prove his engineering capabilities and locate the sunken Boldero. Facing mechanical failures, rival sabotages, and deep-sea hazards, he matures into a capable leader who routinely uses technical ingenuity to pull his crew out of danger.
• Barton Swift wants to complete his revolutionary electrical submarine and secure financial independence for his family. Hindered by his frail health and constant anxiety over business spies, he relies heavily on his son's quick thinking to bring the enterprise to fruition.
• Captain Alden Weston wants to navigate the expedition safely across international waters. Though soft-spoken and unusually polite, his past as a soldier of fortune enables him to take decisive, physical command when the crew is threatened by foreign troops or ocean predators.
• Mr. Wakefield Damon wants adventure and novel travel experiences. Easily startled and given to colorful mild oaths, he puts aside his personal anxieties to assist the team faithfully in times of crisis.
• Mr. Berg wants to defeat the Swifts and secure the treasure for his own firm. Acting with ruthless commercial cynicism, he fails because his crew lacks the technical expertise and adaptability of Tom's team.

In Its Own Voice

"Gracious goodness! What was that, Mrs. Baggert?" he called to a motherly-looking woman who stood in the doorway. "What happened?"

Barton Swift startles as Tom's experimental airship swoops down over their coastal residence at the start of the adventure.

"I can do that part," said Mr. Sharp. "I know some sea captains, and they can put me on the track of locating the exact spot."

The balloonist plans the navigation logistics before the crew attempts to find the sunken bullion.

"Rammed us!" repeated Mr. Swift. "Tom, run out the electric cannon!"

The elder inventor reacts in alarm as a rival submarine tries to disable the Advance under water.

What It's Really About

Beneath its sequence of heroic escapes, the novel serves as a period celebration of early twentieth-century American technological optimism. It contrasts honest, individual craftsmanship—represented by Tom and his father—against the opportunistic greed of corporate monopolies like Bentley & Eagert. The story explores the triumph of mechanical innovation over physical hazards, suggesting that intellect, electrical science, and personal integrity can conquer any natural or human obstacle. Additionally, it examines themes of loyalty and self-reliance, demonstrating how a small, committed team built on mutual trust can overcome state powers, hostile environments, and cutthroat commercial competitors.

Why Read It Today

Readers fond of classic pulp fiction, early scientific romances, and nostalgic adventure stories will appreciate this snapshot of early 1910s popular literature. The book captures a optimistic era when electricity was viewed as a force of boundless potential capable of solving any practical problem.

The prose moves briskly, driven by straightforward action, dramatic cliffhangers, and historical gadgetry. Modern readers should be prepared for period conventions, including simplified international villains, dramatic coincidence, and the characteristic mild humor of the era—such as Mr. Damon constantly blessing his personal belongings. What lingers after finishing is the infectious enthusiasm for invention and discovery, capturing a moment in literary history when the frontier of human knowledge seemed wide open to anyone with a workshop and a bold idea.