J J Actually the textbook for the Navy’s officer level course in oceanography that I took even before the graduate course was written by the renowned oceanographer Sverdrup in the 40s (he also mentioned Croakers if my fading memory still holds me). The basics don’t change, just get more complicated as were learn more. So enough with Croakers and other background noises, on to designing and building subs. R/Jay From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of David Bartsch Alan, From: bottomgun@mindspring.com Alan, The family Sciaenidae is found in almost all oceans (and some freshwaters) of the world. While you may not have a Croaker per se, there is a member of their family in your area that makes LOTS of noise underwater. One of the questions on a graduate oceanography test that I took years ago asked what was the source of the greatest amount of background noise throughout the oceans and the correct answer was Croakers. R/Jay From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Alan James Hi Jay, There are round 700 fish species in NZ waters. About 97% of these you would never come across in your life time. I checked with a freind who is 7x NZ casting champion & repairs fishing reels for a living; he'd never heard of a croaker fish in NZ. I used to draw fish & memorize their scientific names, but haven't come across a Croaker fish. We have a gurnard that "barks" when you land it. But it's nothing like a Croaker. Interesting "The sounds are produced by the beating of abdominal muscles against the swim bladder" Maybe we could exploit the fact that the submarine is similar to a large swim bladder. Alan Hotmail: Powerful Free email with security by Microsoft. Get it now. |