WILL IRON FLOAT?

Sun (Auckland), Volume II, Issue 377, 11 June 1928, Page 13

WILL IRON FLOAT?

UNDER-SEA PRESSURE ANSWER IS. NO! There has been much comment over the unexpectedness of some of the problems set in the education tests for the Navy. One of the questions singled out for censure is this: “Will iron float at a great depth in water?” It has clearly escaped the knowledge of the critics that a very ancient superstition among sailors, and probably among landsmen too,, prompts the setting of this poser, for when we say that So-and-so “will find his level” we are merely adopting as a metaphor the old belief of sailors that iron does float at certain depths. Old Beliefs The belief is that under great pressure water becomes so dense and thick that solid matter will not descend through it; that a drowned man, a sunken battleship, a rent liner, sink only a certain distance, find their level and then float, suspended in water too dense for further descent. Generation after generation of seamen has inherited the legend of sunken objects “finding their level,” just as generation after generation of rustics has inherited the legend that the building of Teuterden steeple caused the formation of the Goodwin Sands, a belief that was common and ancient when it was solemnly handed on by an aged peasant to Sir Thomas More four centuries ago. Miles Deep in the Sea No better type of sailors ever sailed than those who manned the great Challenger scientific expedition, yet when one of their number died and was buried at sea in his shot-weighted hammock they sent a deputation to their officers asking whether it was not a fact that their dead comrade, after sinking to a certain depth, would

“find his level” and float there evermore. Sir John Murray, who helped to solve the Challenger seamen’s problem, lived to be asked a similar question as to the Titanic. The fact is, as Sir John used to explain, that anything that will sink to the bottom of a tumbler will sink to the bottom of the deepest ocean. Upon that fact depends the livelihood of a countless population of weird and extraordinary forms of life whose world is the deep ooze in the abyss of seas miles deep. Food slowly rains down upon them from the waters above; entire fishes, fragments of fishes which have fed fishes keeping higher levels, all sorts of dead creatures from all depths, even to the tiny shelled organisms whose home in life is on the surface, all pour down to the depths. If Gravitation Ceased The water does not stop them. Not that water at great depths is not to some extent compressed. The greater the depth the less the compressibility. At a depth of 24,000 feet pressure reduces the bulk of 10,500 cubic feet of surface water to 10,000 cubic feet. But that does not prevent solid bodies from sinking. Gravity acts there, as everywhere, and a scientific calculation shows that were gravitation to cease the oceans would at once rise 200 feet.

That would arown half England and many another land. But we need not fear that natural laws will fail us. Gravitation will hold the seas down, and will pull to the ocean bed anything which is not buoyant enough to float.

Yet sailors will go on for many a day believing that things “find their level,” and those who set the Navy test papers were not so eccentric as they seemed in asking the question about the sinking of a piece of iron.