There was then on board one of those "patent logs," with an index and helix, which give the speed very exactly for a fixed time.

He looked at the patent log.

The patent log includes a mechanical register that counts the log's rotations as it is being towed.

A variation of this approach is known as a patent log, which is towed from the stern of a ship.

The patent log was invented in 1688 by the English instrument maker Humphry Cole.

They strolled aft to where Captain Dettmar, one foot on the rail, was oiling the gear of the patent log.

The patent log on the taffrail periodically rang a single tinkling stroke for every mile traversed on an errand of faith.

We have held the north-east trade for days now, and the miles roll off behind us as the patent log whirls and tinkles on the taffrail.

Wolf Larsen was smoking a cigar and examining the patent log which the Ghost usually towed astern, but which had been hauled in for some purpose.

The new steamer shot along wonderfully, and the patent log showed a speed of seventeen miles an hour, a speed which as yet no English, French, or American boat had ever obtained.

Mr. Pike put one of the sail-makers at the wheel, and the steward, relieved and starting below, was attracted to the port quarter, where the patent log that towed astern was made fast.

As they approached the end of the Bill he got the patent log from its case and made it ready; then he called Joan on deck to help him in the actual passage round the land, inside the Race.

My restrained excitement had begun again to overmaster me; and for some time my only book had been the patent log that trailed over the taffrail, and my chief interest the daily observation and our caterpillar progress across the chart.

He had been unable to take an observation of any sort since we left Samoa; both his patent logs had been carried away, so that now only the compass remained, and he had not the slightest idea where we were in that great ocean studded with atolls and islands.