patent log: meaning, definition, pronunciation and examples
C2 / Very Low Frequency / Nautical TechnicalTechnical, Historical, Maritime
Quick answer
What does “patent log” mean?
A streamlined device used to measure a ship's speed by means of a rotating spinner towed behind the vessel.
Audio
Pronunciation
Definition
Meaning and Definition
A streamlined device used to measure a ship's speed by means of a rotating spinner towed behind the vessel.
A specific type of mechanical ship's log (nautical instrument) invented in the 19th century, often referring to the Walker's Patent Log or similar devices. It can also be used more broadly to refer to any proprietary or patented speed-measuring device used in maritime contexts.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning. Both variants are archaic technical terms. The device was widely used in both British and American maritime history.
Connotations
Connotes historical sailing ships, navigation before electronic instruments, and traditional seamanship. It has a nostalgic or antique feel.
Frequency
Extremely rare in contemporary use, found almost exclusively in historical texts, maritime museums, or classic sailing literature.
Grammar
How to Use “patent log” in a Sentence
The crew streamed the patent log.The patent log showed a speed of eight knots.We took a reading from the patent log.Vocabulary
Collocations
Examples
Examples of “patent log” in a Sentence
noun
British English
- The first mate went astern to stream the patent log.
- Our reading from the Walker's patent log confirmed the current was against us.
American English
- The patent log was a crucial piece of gear on the clipper ship.
- He carefully reeled in the patent log after taking the noon sight.
Usage
Meaning in Context
Business
Not used.
Academic
Used in historical or maritime engineering papers discussing navigation technology evolution.
Everyday
Virtually never used. Would only appear in conversation among sailing history enthusiasts.
Technical
Used in restoration of classic vessels, maritime archaeology, or writing historical sailing manuals.
Vocabulary
Synonyms of “patent log”
Strong
Neutral
Weak
Vocabulary
Antonyms of “patent log”
Watch out
Common Mistakes When Using “patent log”
- Using 'patent log' to refer to modern GPS or electronic speed sensors. Confusing it with a 'logbook' (the written record). Pronouncing 'patent' as /pəˈtent/ (as in 'patent leather') in the British context.
FAQ
Frequently Asked Questions
No. A 'patent log' is a physical measuring device towed behind the ship. A 'logbook' (or 'log') is a written record of a ship's voyage, events, and navigational data.
It consists of a rotor (spinner) attached to a long line. When towed, the rotor spins proportionally to the ship's speed. The line is connected to a mechanical register on the ship's rail which counts the revolutions and displays the speed in knots.
No, it is obsolete. Modern vessels use electromagnetic or acoustic speed sensors (pitometer logs, Doppler logs) integrated with GPS for far more accurate and convenient speed-over-ground and speed-through-water measurements.
Because it was a specific invention that was granted a formal patent (a government licence conferring exclusive rights). The most famous version was 'Walker's Patent Log', invented by Thomas Walker in the 19th century.
A streamlined device used to measure a ship's speed by means of a rotating spinner towed behind the vessel.
Patent log is usually technical, historical, maritime in register.
Patent log: in British English it is pronounced /ˈpeɪtənt lɒɡ/, and in American English it is pronounced /ˈpætənt lɔːɡ/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “As true as a patent log.”
- “By the log (derived from the practice of using a log).”
Learning
Memory Aids
Mnemonic
Imagine an old SAILOR with a PATENT (official document) nailed to a LOG (piece of wood) floating behind his ship, measuring how fast it goes.
Conceptual Metaphor
MEASUREMENT IS A RECORD (the 'log' records speed as a diary 'log' records events). INNOVATION IS PROTECTION ('patent' implies a protected, improved tool).
Practice
Quiz
What was the primary function of a patent log?