Sounding for Depth

It’s our last full week of NaPoWriMo (National /Global Poetry Writing Month) and the A-Z Challenge. I hope you’re enjoying the A to Z of Depth.

Sounding is a way to physically measure the depth of a body of water. Using a thin rope with a plummet usually made of lead to weight the end, the leadsman would cast the rope into the water and let it fall until it reached the bottom. Then, by counting knots in the rope representing one fathom (six feet) each he would sound the depth. He would yell out “by the mark” and the number for each of the knots, and “by the deep” followed by the last number if the depth was between knots.

The term deep-six, meaning to destroy or dispose of something irretrievably, is believed to come from “by the deep six.” Six fathoms being the depth where something thrown overboard would be hard to recover.

Samuel Clement’s pen name, Mark Twain, came from his years as a river boat pilot. “By the mark twain” (twain being old English for two) was yelled out for the safe depth of two fathoms.

Sounding was used for safety, navigation, mapping, and bathymetry. Bathymetry—from the ancient Greek bathús meaning deep and métron meaning measure—is the study of underwater depths. The first recorded evidence of water depth measurements are from Ancient Egypt over 3000 years ago. Sounding is even mentioned in the bible:

about midnight the shipmen deemed that they drew near to some country; And sounded, and found it twenty fathoms: and when they had gone a little further, they sounded again, and found it fifteen fathoms. Then fearing lest we should have fallen upon rocks, they cast four anchors out of the stern, and wished for the day. ~Acts 27:27-29

In 1802 Edward Massey, a clockmaker, invented a sounding machine.

“The machine was designed to be fixed to a sounding lead and line. It featured a rotor which turned a dial as the lead sank to the sea floor. On striking the sea floor, the rotor would lock. Massey’s sounding machine could then be hauled in and the depth could be read off the dials in fathoms.” (Wikipedia)

Modern Sounding

Today, sounding is high tech, using sonar for echo sounding, along with satellite bathymetry, computer models, and compilations of all these techniques. For one example of using these techniques, take a look at Sounding the Northern Seas.

Though sounding has gone high tech, many ships still have a traditional sounding line for emergencies.

Today’s Poem

How the Music is Stolen

Don’t tell me I’m accepted
to receive your instruction
after my audition then tell me
that you’ll have to tear me down
start from scratch, reteach me everything
starting with scale fingering.

Don’t tell me that my last teacher
who taught me the piano is a percussion
instrument, who changed my fingers to mallets
who made practice fun, convinced
me that I could play anything
needs to be forgotten, yet another
wrong way, keeping me from greatness.

Don’t tell me how lucky I am
that you’ve seen my potential
that my formative years of daily practice
so many nerve-shattering recitals,
contests, and conservatories
would all amount to nothing
if I hadn’t played for you.

How is it that each new teacher
believes he is fated to form
me and shape me, yet needs
to steal a little of the music from
inside me, and replace it with disdain.

This poem was inspired by today’s prompts at NaPoWriMo and Writer’s Digest’s April Poem a Day (PAD) Challenge, and the dVerse Poetics prompt.

Thank you so much for coming by and reading my post. Any thoughts or questions about Sounding? Come back tomorrow for more depth exploration and poetry.