Every stage of life, for people and animals, has had a name. A "maiden" is a girl or young unmarried woman. (Old unmarried women can also be called maidens, but are more typically called spinsters.) At one point a maiden was also automatically considered to be a virgin, although that point is long past. But a "maiden trial" stems more from the virgin belief...the ship's "first" trip out to sea.
Typically, a ship goes out on "sea trials", then is officially christened and goes out on her maiden voyage.
A buzzer sounded; the officer on watch...picked up the bridge phone.
Watchmen were groups of men, usually authorised by a state, government, or society, to deter criminal activity and provide law enforcement. Watchmen have existed in various guises throughout the world and were generally succeeded by the emergence of formally organised policing.
An early reference to a watch can be found in the Bible where the Prophet Ezekiel states that it was the duty of the watch to blow the horn and sound the alarm. (Ezekiel 33:1-6)
The existence of watchmen have also been found in the Ottoman, Greek and Egyptian Empires.
The Roman Empire turned the role of a watchman into a profession by creating two organizations:
the Praetorian Guard thus establishing a rank and file system with a Captain of the Guard.
Vigiles, literally the watch.
The term the Watch then of course migrated into the naval lexicon as well.
"Echo sounder reports the seafloor has risen fifteen hundred feett in the last five miles.
Echo sounding is the technique of using sound pulses directed from the surface or from a submarine vertically down to measure the distance to the bottom by means of sound waves. This information is then typically used for navigation purposes or in order to obtain depths for charting purposes. Echo sounding can also refer to hydroacoustic "echo sounders" defined as active sound in water (sonar) used to study fish. Hydroacoustic assessments have traditionally employed mobile surveys from boats to evaluate fish biomass and spatial distributions. Conversely, fixed-location techniques use stationary transducers to monitor passing fish.
The word sounding is used for all types of depth measurements, including those that don't use sound, and is unrelated in origin to the word sound in the sense of noise or tones.
Technique
Distance is measured by multiplying half the time from the signal's outgoing pulse to its return by the speed of sound in the water, which is approximately 1.5 kilometres per second. For precise applications of echosounding, such as Hydrography, the speed of sound must also be measured typically by deploying a Sound Velocity Probe into the water. Echo sounding is effectively a special purpose application of sonar used to locate the bottom.
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Pacific Vortex, by Clive Cussler. 1982
This annotation comes from the 2010 Bantam Books Mass Market Edition, and from Wikipedia unless otherwise identified.
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