Did You Know

Literature, Art & Science

onnectionsCForce in MotionWould you and your students enjoy a Treasure Hunt? Mystic Seaport abounds with simple and compound machines, many of them in use every day by staff. You can watch a cooper shaping staves to make a bucket or a shipsmith turning a hook. You can join our Demonstration squad and perhaps turn a rope jack or capstan. Tour on you own, or book one of our special Force and Motion Tours. http://www.mysticseaport.org/learn/k-12-programs/fi eld-trip/guided-tours/

Sailing Perhaps you have an interest in learning to sail. Check out our sailing classes.

We even have them for homeschoolers!www.mysticseaport.org/sailing

NavigationIt’s a whole wide world out there. Try out tools of navigation in our Nautical Instruments Shop or simply sit back, relax and watch a planetarium show.

Thank you to Mystic Seaport colleagues Andy German, Fran Muller, Erik Ingmundson and Barbara Jarnagin for research and documents used as reference materials for this article. Thanks also to Maribeth Bielinski, Dan McFadden, Andy Price and Suki Williams for their assistance.

Fishing for ScienceWhat Does a Fishing Schooner Have To Do With STEM Education?

STEM Education (Science, Technology, Engineering, Mathematics) is a familiar buzzword. How can we incorporate more of these elements in our everyday educational endeavors? By taking curriculum studies into the fi eld, students can begin to connect what they learn in the classroom to what they see in the world around them.

What does “Mystic Seaport: The Museum of America and the Sea” conjure up for you? You probably think of us as a History Museum. We are, and we’re very good at presenting interesting artifacts from the past in a way that stimulates the imagination and brings on questions which link the past to the present. We are also very good at telling stories about how artifacts were used, the people who used them, and how emerging technology changed lives, and history. Some of our most interesting artifacts are boats, with all the bits and pieces that make boats move, and some of our most interesting stories tell of the work done on vessels as they move. What can boats teach us about science and technology?

Let’s start with something simple: Simple Machines. By most counts, there are six: the Inclined Plane, the Wedge, the Pulley, the Wheel and Axle, the Screw and the Lever. Now, let’s take a boat, and by way of example, let’s use the Museum’s historic fi shing schooner, the L. A. Dunton.

Photo credit: Mystic Seaport(For more about the L. A. Dunton, see the Do You Know? section of this article.)

4. Pulley Hoist How Do You Lift Heavy Things (Like Your Body Weight)?A pulley is an elegant simple machine, and by using two or more

of them, a student can gain a mechanical advantage. What does that mean? Simply, mechanical advantage means that the force (push or pull) produced by the machine (output) is greater than the force ap-plied to the machine (input) because the machine increases the dis-tance through which the input force is applied. Sit in the seat; can the pulleys help you lift yourself off the ground? How many feet of rope do you need to raise yourself a foot? Might pulleys help sailors at sea accomplish diffi cult tasks like raising heavy sails?

5) Turbulence Table: Does Hull Shape Matter?The part of a boat that rests in the water is called the hull, and its

shape determines how well it moves through the water. The tur-bulence table shows how different hull shapes move, by giving stu-dents a shallow “current” of water along the table in which they can place different hull shapes and observe the behavior of the current’s “boundary layers” (the water directly surrounding the hull). Do the layers fl ow in an orderly manner (laminar fl ow) or in an agitated manner (turbulent fl ow)? Do we see waves forming in front of the hull or eddies forming behind the hull? How would this affect speed and effi ciency?

6) Degrees of List: How Important is Proper Cargo Loading?A boat fl oats because the weight of the boat is equal to the weight

of the water it displaces, or pushes aside. Gravity pulls the boat down into the water, but the water pushes back up, creating buoy-ancy. When a vessel is perfectly level, its center of gravity and center of buoyancy are in line and the vessel appears vertical in the water. That is, until we start loading on cargo! Students can try their hand at cargo handling. Can they avoid capsizing the vessel? Think of all those forces at work.

7) Pitch, Yaw and Roll: More Forces to Contend With?A sturdy, wall-mounted hull gives students the opportunity to

explore three more ways that ocean forces affect the movement of a vessel. Pitch is the up and down movement as a boat moves forward in heavy seas. Yaw is the rotation of a vessel around its vertical axis. Roll is the side-to-side rotation of a vessel around its longitudinal axis. Can good boat design and construction mini-mize the effect of these movements? Which one(s) will make you seasick?

Geography is Destiny

Find out how your students can experience Mystic Seaport here: http://www.mysticseaport.org/learn/k-12-programs/fi eld-trip/

Photo credit: Mystic Seaport“Force in Motion at Sea” Exhibit in the Discovery Barn at Mystic Seaport

Photo credit: Mystic Seaport“Force in Motion at Sea” Exhibit in the Discovery Barn at Mystic Seaport

Photo credit: Mystic Seaport“Force in Motion at Sea” Exhibit in the Discovery Barn at Mystic Seaport

Photo credit: Mystic Seaport“Force in Motion at Sea” Exhibit in the Discovery Barn at Mystic Seaport

Geography is Destiny

The fi shing schooner L. A. Dunton has two stories. One is the vessel herself, built almost a century ago and now an integral part of the Mystic Seaport’s collection of historic vessels. But the schooner’s other story began about 12,000 years ago, when the last great North American ice sheet began to recede, leaving behind vast piles of rocky debris (terminal moraine) which we know now as Cape Cod, Long Island and the islands between them. Beyond, to the east, on the continental shelf, we fi nd broad plateaus. When the ice sheet melted, the sea rose and submerged the plateaus, but their highest points, known as the Banks, are only 100 to 600 feet below sea level. Around the Banks fl ow two distinct ocean currents. One is the Gulf Stream carrying its warm waters from the Gulf of Mexico north-northeast along the Banks’ eastern edge. Nearer to land, the Labrador Current brings cold water south. Over the shallow Banks, where sunlight can reach the bottom, the warm and cold currents mix and create an environment in which an abundance of marine organisms fl ourish. Schools of fi sh are attracted to the plentiful food supply.

Where There Are Fish, There Are Fishermen

Since the 1500’s men have found their way to the Banks. First Europeans, and later the settlers of North America fi shed the rich waters. Grand Banks, off the coast of Newfoundland, Western Bank, off the coast of Nova Scotia, and Georges Bank, just 100 miles off of Cape Cod were key destinations. For 300 years, fi sh were caught with handlines, one fi sh at a time. On board the fi shing boat, fi sh were headed, gutted, split and salted to preserve them until the boat could return home with the catch. What kind of fi sh were they catching? Cod. Migrating fi sh with voracious appetites, often weighing 20 pounds or more, cod were easy to catch and easy to preserve. (Fun Fact: In 1602 Cape Cod was named by English Explorer Bartholomew Gosnold because of the plentiful cod fi sh he found off its shores.)

The More Fish, the Better

The demand for fi sh increased, and New England fi shermen adopted a more effi cient way of fi shing. Large sailing vessels called schooners could travel quickly from port to the Banks, each carrying up to ten small, fl at-bottomed boats called dories stacked on her deck. A good schooner captain could locate the best fi shing area by sampling the sand, clay and rock of the bottom, using a lead line (a weighted tube fi lled with tallow to which bottom material could stick) and choose where to lower the dories for fi shing. Two men to a boat, the so-called “dorymates” would bait 300 to 500 hooks on small lines called gangings which hung from a heavy trawl line 1800 feet long. Each dory would be lowered over the side of the schooner and the mates would row away from the schooner, playing out the heavy trawl line until it settled near the bottom. Here, the bait (usually a greasy little fi sh called capelin) would attract cod, haddock, hake and halibut. These were hauled in by the dorymen, rowed back to the schooner, then processed and salted or put on ice until the schooner could return to market.

“Leaping, and plunging bows under” Illustration by Milton J. Burns

One Man’s Dream

Felix J. Hogan was born in 1872 in Newfoundland, Canada, and like many young men of his time and place, he grew up fi shing for cod in the coastal waters near his home. As a teenager, he came south to Massachusetts to work on fi shing schooners leaving from the ports of Gloucester and Boston and sailing the 100 miles to the Georges Bank or the 800 miles to the Grand Banks (off Newfoundland). A hard worker, he rose from dory fi sherman to spare skipper to captain, and by 1920 he was ready to have his own boat. He wanted the very best; a deep-draft schooner with plenty of cargo space for fi sh, that would be very seaworthy, very maneuverable and very fast. He wanted the kind of two-masted schooner called a semi-knockabout that had been designed by a famous naval architect named McManus. It had an elongated bow and a shortened bowsprit so that it was safer for the fi shermen to reef and furl the headsails in bad weather. He went to the famous shipyard owned by Arthur D. Story in Essex, Massachusetts, and in six months, Mr. Story’s crew built his schooner from oak and pine. Lewis A. Dunton, a Maine sailmaker who held a fi nancial interest in the vessel, offered to make a set of sails for free if Captain Hogan would name his schooner after him. Captain Hogan agreed, and on March of 1921, the L.A. Dunton was launched. The eight sails were very large, about 8,000 square feet in area. The old-timers on shore told Captain Hogan that his vessel would never be able to carry such a big mainsail. According to one witness, Captain Hogan retorted, “Well, if she won’t carry it, she’ll drag it.”

From 1921 until 1932, the L. A. Dunton served him well. Captain Hogan and his crew fi shed the Georges Bank and the Grand Banks, making up to eight trips a year, each lasting approximately one month. In her fi rst year of fi shing, The L. A. Dunton brought back 268,000 pounds of fi sh. How many tons is that? Each time she returned to port, the catch was sold and each of the 20 fi shermen was paid a share of the gross receipts. The amount paid was highly dependent on the market price and the species of fi sh caught (halibut was highly desirable, and brought ten times the price of cod). In 1923, a man who went on all eight of the L. A. Dunton’s trips for halibut made $876 – enough to buy a Ford motorcar.

Fishing  Schooner  L.A.  Dunton  under  sail  

Too Much Success?

By the 1930’s, technology had taken its toll on the fi shing industry. Two-masted schooners like the L. A. Dunton were obsolete, even those with auxiliary engines. They were replaced with trawlers powered by engines fueled with heavy crude-oil. The trawlers dragged a conical net called an otter-trawl across the sea’s bottom, raking in great quantities of fi sh. By the 1960’s eastern-rig draggers were introduced and further depleted the fi shing stock. Overfi shing had its consequences; in the 1990’s the Georges Bank and Grand Banks were closed to most commercial fi shing in the hopes that one day the Banks will recover and once again be rich with fi sh.

The L. A. Dunton Today

In 1963, Mystic Seaport acquired the L. A. Dunton. She is now a National Historic Landmark and is a tangible reminder of a bygone era in fi shing history. Her design served her well: she was seaworthy, fast and agile and got her fi shermen to the fi shing grounds and safely home again in record time. Don’t you think she is a worthy inspiration for our new exhibit?

by Nancy Hughes, Mystic Seaport Educator

We’ll board her by using the gangway, an Inclined Plane. Her hull acts as a Wedge when she’s moving through the water. Systems of wheels and ropes called block and tackle act as Pulleys to raise and lower sails and small, open boats called dories. The helm utilizes a Wheel and Axle system to turn the rudder. When fi tted with an engine, the propeller was a Screw. The dories were used for fi shing and every time a fi sherman in a dory pulls an oar through the oarlock, he is using a Lever. Each of these simple machines makes our work or the work of the boat easier, faster, and safer.

Once you know what you’re looking for, Mystic Seaport is a treasure trove of simple and compound machines and can help you readily make connections between technology today and that of the past. By way of introduction, and to make that connection immediately accessible to our visitors, Mystic Seaport has recently opened an exciting new exhibit in the Discovery Barn called “Force in Motion at Sea”. Here, a wide range of hands-on activities invite inquiry-based exploration of key concepts in physics and tie these in with challenges faced by sailors at sea, especially those fi sherman once aboard the schooner L.A. Dunton.

Elements of the new exhibit called “Force in Motion at Sea” in the Discovery Barn at Mystic Seaport:

1) Simple Machines: Do They Make Work Easier?Students have a chance to identify and try out six simple

machines. Each provides an opportunity for experimentation. Results can be observed, measured and recorded. What are other examples of simple machines in our daily life?

2) Compound Machines: Can You Put Simple Machines Together To Perform More Complicated Tasks?In a wall-mounted case, a fanciful Rube Goldberg type

apparatus fascinates the student who dares to turn the handle. How many simple machines can you identify? Can you see how a simple machine can change the direction of force? Can you see how the output force of one machine becomes the input force of another?

3) Wind Table: How Does a Boat Sail?The wind blows where it will; we cannot control its direction

or strength, but sailors know how to use it. Our wind table uses a fan to simulate the wind and its directional force. A student chooses a small boat and affi xes a sail of varying shape. On the slick table surface, it is easy to sail away from the “wind” (“downwind”). But now, try sailing “upwind”: how can you do this? A knowledge of physics is most helpful for a sailor, for he or she must angle or point his or her boat and its sails to maximize their curvature, and must change his or her direction by “tacking”. How important is maneuverability to a vessel at sea?

Photo credit: Mystic Seaport

Photo credit: Mystic Seaport