Miscellaneous
Marine distance measurements are expressed in terms of nautical miles. A nautical mile is significantly different from a common or statute mile. The conversion is 1 nautical mile = 1.151 statute miles, or approximately 6076 ft ( vs. 5280 ft for a statute mile. )
Why such a confounded thing as this? Here's why:
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Side-scan sonar is a modern method of underwater imaging that can produce remarkably detailed and realistic views of shipwrecks and other bottom features using sound rather than light.

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Another entry from the Way-back machine:


"Gentleman George"
by Dan Berg
Note: George Hoffman passed away January 14, 1997, about a year after this article was written. His death is a great loss to the diving community and he will be missed by us all.
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Artifacts recovered after long immersion in salt or freshwater require conservation treatment if they are to last. On exposure to high concentrations of oxygen in the air, iron artifacts will bloom into piles of rust. Wood will crack and split if dried out improperly. Organic materials will crumble to dust.
The manual below details conservation methods for many types of materials and artifacts.
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Wire dragging is an operation used to locate and/or reduce the navigational hazard of a sunken wreck, rock, or other obstruction.
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Alpha-Numeric Signal Flags
In this modern age of radio, these signal flags are a quaint anachronism that is no longer used, although they were once very important in ship-to-shore and ship-to-ship communications. Each flag stands for both a letter value and a shorthand message. The letters are expressed here in the modern international phonetic alphabet, in which A-B-C would be spoken Alpha-Bravo-Charlie (see below).
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