‘Tin Fish To Plot Bed of Sea’
52 years ago this was a headline in Electronics Weekly’s edition of May 17 1961.The story opens:
‘The magnetic contours of the bed of the Mediterranean will be traced by two “tin fish” developed, designed and manufactured by the Electronics Division of Bruce Peebles & Co Ltd of Edinburgh.’
‘The “fish” – outwardly metal cylinders 2ft long and 4 – 5 inches in diameter – carry proton spin magnetometers.
‘Towed about 1,000ft behind a survey ship, these pick up and relay signals directly related in frequency to the strength of the earth’s submarine magnetic field.’
‘The magnetic contours can thus be taped and finally plotted in the same way as the ordinary physical contour of the sea bed.’