The logbooks of naval ships are especially valuable for unique information about the world's oceans. Much of what we know about this part of our blue planet and its atmosphere starts in these records. 

A Navy ship’s logbook was designed to serve many functions. It is a daily diary of events, ranging from routine ship’s business to eyewitness accounts of notable occurrences—powerful storms, discoveries in uncharted seas, and legendary sea battles. 

It was also an indispensable tool that helped guide ships efficiently and safely across the sea. Every change in course and speed, the landmarks sighted, and depth measurements were all recorded. The navigator used this information to determine the ship’s position on the high seas and to avoid reefs and rocks when nearing the shore. The weather was keenly observed. In the ages before satellites, this was the only way to know when a storm was coming in time to safeguard the ship from damage and disaster.  

After the voyage, the logbook contributed to the collected knowledge of the sea. This legacy continues today.

To learn more about the importance of each section, click on the highlighted areas below.

Original record in the National Archives catalog.

"In order to understand what the weather will be like in the future, 

we need to understand what it was like in the past."  

Dr. Kevin Wood

Seas of Knowledge

A collaborative project between

Extended Citations + Links to original sources

H: Arnold & Dent Box Chronometer, ID Number ME.314612. Smithsonian National Museum of American History.

Knots & Fathoms: Chip Log, ID Number 1934.9. Mystic Seaport Museum.

Taffrail (Patent) Log, ID Number TR.308558. Smithsonian National Museum of American History.

Courses: Ritchie Liquid Compass, ID Number PH.309656. Smithsonian National Museum of American History.

Wind: (Direction and Force:  Lehmann & Duval, Lithographer, and Charles Crillon Barton. U.S. Ship Pennsylvania. Charles Stewart Esq. Comr. / Drawn on stone by Charles C. Barton, U.S.N. ; Lith. & Pubd. by Lehmann & Duval Philadelphia., ca. 1840. Library of Congress.

Weather: Drawing, Cloud Study; Frederic Edwin Church (American, 1826–1900); USA; brush and oil paint, graphite on paperboard.; 1917-4-586. Smithsonian Design Museum Cooper Hewitt.

Temperature (Air and Water):  Jenkins, T. A. (Thornton Alexander). (1869). The barometer, thermometer, hygrometer, and atmospheric appearances at sea and on land as aids in foretelling weather: with brief rules for their use, and the practical application of their separate and combined indications as weather guides. Washington: Govt. Print. Off.

Barometer: Adie Mercury Barometer No. 1711, ID Number nmah_1419575. Smithsonian National Museum of American History

Remarks: Soley, James R. The Boys of 1812 and other Naval Heroes. Estes and Lauriat, 1887.

Noon Observations:  Eight Bells; Winslow Homer (American, 1836-1910); etching on wove paper; 1935.52; Addison Gallery of American Art, Phillips Academy, Andover, MA.

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This project is supported by a Digitizing Hidden Collections grant from the Council on Library and Information Resources (CLIR). The grant program is made possible by funding from The Andrew W. Mellon Foundation.