The Friday Morning Lecture Series presents:

"Before GPS: the Early Days of Navigation" presented by J. Leon Poirier
Friday, April 13, 2012
at 10 a.m. at the Chelmsford Public Library

In a fascinating and enlightening presentation J. Leon Poirier, a senior navigator in the U.S. Power Squadron, will demonstrate many of the instruments that early sailors used to guide them in the discovery of the new world. Using replicas of navigation instruments from the 15th to18th century Dr. Poirier will explain how sailors managed to travel around the globe.

Sailors found their way over the earth's oceans long before words like sextant, nautical almanac, chronometer, GPS, LORAN, radar, etc. became part of our lexicon. They used instruments with names like kamal, quadrant, cross staff, astroblade, back staff, hour glass, chip-log, traverse board and nocturnal. Christopher Columbus, Ferdinand Magellan and Sir Francis Drake all used these early instruments to determine their latitudes during their voyages of discovery. It wasn't until the late 1700's, with the advent of the chronometer, that navigators could determine their longitude. Leon has made replicas of these 14-18th century navigation instruments and has many of them on display now in the Display Case in the library's foyer. Meet Leon at this special presentation, and through him learn about some of the early explorers who fearlessly traveled our globe while most of people trembled in fear at the thought.

J. Leon Poirier has taught navigation for 30 years. He has also taught electrical engineering at UMass Lowell and at Tufts University. He holds BS, MS and Ph.D degrees.