Save Our Ships! Navigation on the High Seas

Introduction

Navigation is determining where you are and how to get where you're going. Navigation tools help you travel from one place to another efficiently and safely. Early sea navigation depended upon a mariner's ability to determine latitude by observing the height of the sun in daylight and the North Star and major constellations at night. Such observations were not exact and could be unreliable. Beginning in the 13th century, advancements in navigational tools and scientific methods made navigation more exact and travel by ship safer; however, by the early 18th century, ships still lost their way frequently, with sometimes disastrous results. In this problem- based lesson, students read about the Scilly disaster of 1707, determine its causes, and then choose and explain which navigational tools might have prevented the disaster.

Objectives

In this lesson, students:

• identify the cause(s) of the Scilly naval disaster of 1707 • place the development of navigational tools in chronological order • problem-solve to figure out what navigational tools could have prevented the Scilly disaster • use their knowledge of navigational tools to answer the question “How did mariners use navigational tools to solve the challenges of early oceanic travel?”

Materials

• Navigational Tools Graphic Organizer • Scilly Naval Disaster of 1707 • Timeline of the Development of Navigational Tools • Navigational Tools Cards • scissors • tape

Strategy 1. Ask students to think about the kinds of tools we have today to help us find our way when traveling. As students share their ideas, record them on the board or document camera. 2. Remind students that before the air travel was invented, the only way to travel between continents was by ship. In collaborative student groups, ask students to brainstorm the challenges or problems of navigating across the oceans. Students record their thoughts in Column 1 on the Navigational Tools Graphic Organizer. Ask students to share ideas while someone records student ideas on the board. 3. Explain that navigational tools evolved over time to make transoceanic travel safer and more exact. Pass out the Navigational Tools Timeline to students and read through the timeline. Explain that navigational tools improved over time, and that problems with some tools led to the development of other tools. 4. Distribute the Navigational Tools Cards and read through them with the students, answering any questions they may have about the tools. Make sure students have a clear understanding of each tool and how it worked to make sea travel safer and more exact. 5. Have students cut out the Navigational Tools Cards and tape them together in chronological order of their development, left to right. 6. Give each student a copy of the account of the Scilly Naval Disaster of 1707, and read the account aloud while students follow along. Alternatively, you can call on students to read aloud a paragraph at a time, or employ the "popcorn" reading method. 7. Place students in collaborative groups and ask them to read through the account a second time and identify the cause(s) of the disaster. You may want to have students underline and/or highlight the causes as they find them. Have students record the causes in Column 2 of the Navigational Tools Graphic Organizer. 8. Using the Navigational Tool Cards, ask students to find tools that might help solve the problem(s) that caused the naval disaster. They should record the tools in Column 3 on the Navigational Tools Graphic Organizer. Answers must include explanation of how the tools would help solve the problems. 9. After students have recorded their ideas onto their graphic organizer, ask students to share answers with the class. The other students should add ideas to their lists. Record student ideas on the board. 10. To conclude this lesson, ask students to write an academic summary in response to the question, “How did mariners use navigational tools to solve the challenges/problems of early transoceanic travel?” Students should provide 2-3 pieces of evidence to support their answers.

Lesson Extensions 1. Students can research the navigational tools mariners use today, and compare them to what mariners in the 18th century used. How are they similar? If they are similar, have they changed over time? How are they different?

2. Have students make a quadrant (there are several websites that provide directions). Hang a Styrofoam ball from the ceiling, then have students use the quadrant to find their latitude. Then turn off the lights and ask students to try and find their latitude. Discuss the trouble you had finding latitude at night when sailing under a cloudy sky, and relate that to the difficulty mariners might have had sailing under those conditions.

This lesson was written by Colonial Williamsburg Master Teacher Tracy Middleton, San Marcos, CA, for the October 2014 Teacher Gazette.

SCILLY NAVAL DISASTER OF 1707 The Isles of Scilly, a small group of islands (some only the size of large rocks) just off England’s west coast, was the site of one of the Royal Navy’s worst maritime disasters. A British fleet of 21 ships, under the command of Admiral Sir Clowdesley Shovell, was headed home to Portsmouth from duty in the Mediterranean Sea as a part of the War of Spanish Succession. “It was a dark and stormy night” describes the evening of October 22, 1707. The British fleet had been sailing in foggy and rainy weather since leaving Gibraltar, making navigation difficult. In the 1700s, navigation at sea was an inexact science. Longitude was determined by “dead reckoning,” which is determining location based on how far you’ve travelled from your last known location based on landmarks or the stars. The bad weather compounded the problem by limiting visibility and blowing the ships off course. Shovell called a conference of the ships’ masters to determine the fleet’s exact location. The consensus of the sailing masters was that the ships were close to Ushant, France. Only one master disagreed, stating that they were nearer the Isles of Scilly. Shovell, believing that he was at Ushant, headed west, thinking he was headed into the English Channel toward Portsmouth. Unfortunately, he was many miles further west and north than the inexact calculations predicted—near to the Isles of Scilly. His flagship, the Association, ran aground on the westernmost part of the Scilly Isles. By all accounts, the Association sank rapidly, quickly followed by the Eagle and the Rumney, losing all men on board. The Firebrand sank shortly thereafter. Various accounts of the event list the number of sailors lost between 1,400 and over 2,000. At that time, few sailors could swim. Various logs and journals from other vessels in the fleet show that it was miraculous that no other boats wrecked. The remainder of the fleet made it to Portsmouth on October 25, 1707. Oct. 23. At 6 Sir Cloudesley Shovel made ye signal to wear, at the same time we all made saile, hauling up E. [east] by S. [south], E.S.E. [east southeast] and S.E. [southeast] At ½ past 7 fell in with ye islands of Scilly; the Genll fired one gun, as we plainly saw, and immediately lost sight of him; then Rear Admiral Noris fired four guns, hoisted several lights and wore, and put all his lights out, at ye same time made the light on St Mary's under our lee bow. At 7 a.m. (on 23rd) saw seaven saile wch I judg'd to be some of ye separated fleet. The Shipwreck of Sir Cloudesley Shovell, on the Scilly Islands in 1707. From Original and Contemporary Documents Hitherto Unpublished (Read at a Meeting of the Society of Antiquaries, London, Feb. 1, 1883) By James Herbert Cooke, F.S.A. The Scilly naval disaster in 1707 prompted the British Parliament to pass the Longitude Act in 1714. It included the Longitude Prize, which offered £20,000 to anyone who invented an accurate method of determining longitude at sea. Sir Isaac Newton helped write the Act, including a list of methods of finding longitude that had already been tried but were not effective.

Navigational Tools Chart

What challenges are there to What problems did the fleet What navigational tools could finding where you are in the encounter on its voyage in have helped them? How? middle of the ocean? 1707?

Answer the following question in the box below. How did mariners use navigational tools to solve the challenges/problems of early transoceanic travel? Be sure to include 2-3 pieces of evidence to support your thesis, and write in complete sentences.

Timeline of Navigational Tools and Legislation

13th Century • portolan charts • first documented use of astrolabe for sea travel

15th Century

• quadrant • logbooks

16th Century

• chip log • traverse board • back-staff • cross-staff (first recorded date of use – 1514)

18th Century

• Longitude Act passed in Britain • logbooks used as official documents • marine chronometer

Navigational Tool Cards Mariners’ Museum images and more information can be found at http://ageofex.marinersmuseum.org

Navigational Tool: portolan charts—navigational Navigational Tool: astrolabe—an angle- maps based on compass directions and estimated measuring device for measuring the sun and stars distances observed by mariners in the areas of astronomy and astrology, later adopted for use at sea Purpose: useful near the shorelines to identify and go to or avoid coastal features and ports Purpose: measures the angular heights of the sun

[Portolan atlas of the Mediterranean Sea, western Europe, and the northwest coast of Africa]. Joan Oliva, 1590. Library of Congress Maps and Geography Division Mariner’s Astrolabe, Portuguese, 1645, by Nicholao [2005634035]. Ruffo, The Mariners’ Museum (2000.52.1).

Navigational Tool: quadrant—a device that was Navigational Tool: chip log—a basic one-fourth of a circle, used by mariners to speedometer in which a line was knotted at measure the height of the Pole Star. By knowing regular intervals and weighted to drag in the the height the Pole Star was when viewed from a water particular port, mariners used the quadrant to Purpose: to determine the speed of a vessel help them navigate to port cities.

Purpose: to help mariners determine latitude

Loch à plateau [Ship log and associated kit from the Musée de la Marine, Paris] Rémi Kaupp, Wikimedia Quadrant, circa 1650, Peter Ifland Collection, The Commons. Mariners’ Museum (1998.39.10).

Save Our Ships! Navigation on the High Seas

Navigational Tool: logbook—originally a book for Navigational Tool: traverse board—a navigation recording the ship’s speed, the logbook became a device consisting of a small board marked with record of anything related to the ship or voyage the four points of the compass with eight holes (i.e. direction and speed, cargo, weather, any bored at each point to represent each half hour in special event on the ship, and some included a watch and used to peg the courses made by a drawings) ship in each half hour

Purpose: to record the trajectory of the vessel as Purpose: used to track a ship’s course and the well as to detail cargo and events that occurred on distance traveled ships

Traverse Board, Reproduction, Donated by L. Eichner, Logbook entries August 11-13, 1774, from the Logbook 1957, The Mariners' Museum (1957.19). of the Snow Minerva, 1772-1776. The Library at The Mariners’ Museum.

Navigational Tool: marine chronometer—a clock Navigational Tool: back-staff (also known as that is precise and accurate enough to be used as Davis Quadrant)—a device that used the shadow a portable time standard, providing a means of of the sun to determine the altitude of the sun navigation by the sun, moon, and stars Purpose: to determine latitude Purpose: to help mariner determine longitude when at sea out of sight of land

Back-Staff, 1711, by Walter Hensaw, Peter Ifland Collection, The Mariners’ Museum (1998.69.151).

Ferdinand Berthoud, marine chronometer no.3, 1763. World Imaging, Wikimedia Commons.

Navigational Tool: cross-staff—an instrument Navigational Tool: nautical almanac—a that helped mariners determine the angle publication containing a set of tables that use between the horizon and the sun, and used when accurate measurements of the angle between the sailing to unfamiliar places moon and known stars

Purpose: to determine a vessel’s latitude on the Purpose: helps mariners navigate using the sun, open sea moon, planets, and stars

Back-Staff, Peter Ifland Collection, The Mariners Museum, (1998)

Navigational Tool: The British Longitudinal Act— an act that set up a Board of Longitude, which established a £20,000 prize for the person who could invent a means of establishing accurate lines of longitude

Purpose: to examine how to gauge correct longitudinal positions at sea