Any exhibit that can document a link between wooden boats and toasters is certainly thinking big.

Mystic Seaport Museum, where it’s all about the sea, makes the connection and restores maritime history to its forgotten place in one of the 20th century’s great design movements.

“Streamlined: From Hull to Home” recounts the evolution of a signature style of the Depression era, when rounded corners, chromed surfaces and horizontal lines gave a look of futuristic speed to everything from trains and cars to vacuum cleaners and, yes, toasters.

Less well-known is that “streamlining,” as the style was known, had its origins in boatbuilding, which strives for maximum speed through minimum water resistance.

“This is a story that hasn’t been told before,” said Elysa Engelman, the museum’s director of exhibits. Why that’s so isn’t clear, because the progression of streamlining from boats to other forms of transportation seems logical enough.

Refinements in boatbuilding were needed every time a new power source came along, be it muscle, wind or engines.

An early example is a 31-foot mahogany racing launch from the Seaport’s collection. The Panhard 1 dates from 1904 and used a heavy automobile engine. The boat was built to go as fast as the engine’s weight would allow, which is just the principle that became known as streamlining.

The concept came into its own in the 1920s as engines became faster and traditional “displacement” hulls that moved through the water gave way to “planing” hulls that skipped nimbly over the surface.

A 16-foot craft that’s probably from a Mystic shipyard is a good example of a newer design. Water was forced between the divided bows of the Hickman Sea Sled, creating lift that let the boat go faster.

The emergence of powerboats created a cultural obsession with speed, and soon old records were being shattered. Before 1900, no vessel had traveled faster than 40 mph, but by the ‘20s, hydroplaning helped some exceed 100 mph. Powerboat racing became popular, and sometimes the opponents were not other boats, but trains.

The speed craze caught on with other kinds of transportation, and so did some of the methods used to streamline boats, such as rounding corners to reduce resistance.

A 1936 short-subject film explores how Chevrolet was starting to redesign automobiles in this way.

“The development of more complete streamlining for motor cars will be the problem of engineers of tomorrow,” the stentorian-voiced narrator intones. “Someday this problem will finally be solved.”

But already, innovations like turret tops, slanted windshields and rounded fenders were hailed as practical improvements that also created “new beauty and dignity of appearance.”

The same could not be said of the experimental Dymaxion car, a bulbous and preposterous creation of designer and futurist R. Buckminster Fuller that nonetheless incorporated streamlining principles. It looked like an aerodynamic camper, moved on three wheels and had a keel like a boat. Though it never caught on, a film clip reveals that it parallel-parked beautifully.

A cross-pollination of influences fueled developments on land, at sea and in the air. A surplus of airplane engines after World War I helped create the powerboat. Planes cut air resistance as fabric-covered wooden frames were entirely enclosed by a metal skin. Locomotives were similarly transformed.

The results were on display at the Chicago World’s Fair of 1933-34, a celebration of technology. Visitors saw streamlined trains like the Zephyr and M-10000; cars like the Dymaxion and the droopy-looking Chrysler Airflow; and even the German airship Graf Zeppelin.

But the practical aspects of streamlining soon took a back seat to its distinctive look, and a technological trend became an original American style, applied to things that didn’t need to go fast or, indeed, didn’t move at all.

Which brings us back to the toaster. A display of a dozen or so of the kitchen mainstays, arranged chronologically, shows how streamlining took hold in manufactured goods of the 1930s. But it also lays out a broader process by which many items begin as inspired though artless inventions, then take on a style, then lose it to cost-cutting.

Toaster No. 1, vintage 1915, is an unlovely contraption of stamped metal that performed a hitherto-unknown feat: It cooked bread without fire. Subsequent models reflect increasing ease of use as heating elements, which could leave the bread smoking and inedible, were engineered to turn off automatically.

Gradually decorative patterns are seen in the metal, and by the late 1930s, the moving parts disappear inside the same kind of sleek exterior shell that enclosed trains and planes.

After a few decades, toast ceased to be a breakfast-table miracle, and the toaster underwent a parallel decline. Though still necessary, it no longer justified the expense of design, and the last examples are functional and ordinary.

The same process plays out with a collection of outboard motors, which begin in 1914 with no hint of aesthetics and by the ‘30s also take on a simplifying shell. Two design principles are at work: absorption of many shapes into one form, and the elimination of extraneous details.

The motors are arranged in the innermost of three roughly concentric circles that make up the show. Beyond it is a circle of boats, and at the outer edge are text panels that tell the story, along with the toasters and other streamlined household goods, like cameras, roasting pans and tape dispensers. The patterns of horizontal lines that adorn them were called “speed whiskers.”

The exhibit is curated by Matthew Bird, an industrial designer and professor at the Rhode Island School of Design.

In the lobby outside the gallery, the story of one object serves as either introduction or postscript, depending on when you encounter it. The 1937 Electrolux Model XXX is not your ordinary old vacuum cleaner. It’s an icon of American industrial design, created by Connecticut designer Lurelle Guild.

One way companies kept people spending money during the Depression was to reimagine existing products so they seemed new and worth paying for. We don’t see what older vacuums looked like, but it was probably nothing like this: a miniature, chrome-covered train, gliding across the floor on sleds, with speed whiskers whooshing along the sides.

A million sold in the first year, perhaps aided by a subliminal impression that, barreling down the track of humdrum housework, they could bring better times all the faster.

But first World War II intervened, spurring new design sensibilities. These were sometimes practical, as with the need for boats that were fast but sturdy enough to hold soldiers and supplies. The old displacement hull was tempered with features of the speedboat to create the “Deep V,” used famously in the Patrol Torpedo boat, like future President John F. Kennedy’s PT-109.

With peace came groundbreaking new technologies, which in turn suggested style as the cycle began anew. Jets and rockets were the emerging signs of the future, and their pointy, vertical forms started to show up in things like fins on cars.

Streamlining’s day was over. Speed had brought the style to life, but a revved-up society moving ever faster now left it behind.

j.ruddy@theday.com

If you go

What: "Streamlined: From Hull to Home"

Where: Mystic Seaport Museum, Thompson Exhibition Building

When: Through Aug. 25

Hours: 9 a.m. to 5 p.m. daily

Admission: $28.95 adults, $26.95 seniors, $24.95 youths 13-17, $18.95 children

Information: mysticseaport.org