Science Notes: (2) Near Bottom Currents
The near bottom currents were to be investigated using a tripod with a camera and directional vanes, and a sphere on the sea floor equiped with an Electomagnetic log. Again my notes are reproduced more or less verbatim, added words are indicated [thus]…
Near bottom currents: Tripod
Tripod carrying a camera (open shutter, flash actuated) and several vanes and other current indicating devices and a compass. Moored with subsurface buoyancy [to bring it back to the surface and marked by] a Dhan with radar reflector. Used to investigate current fluctuations near the ocean floor and to look for any indications of Ekman spirals.
Tripod = 165lb plus 405lb weights (in water); total 700lbs in air.
Lowered first at position “A”, 4 photos per minute for 8 hours. A pinger on the tripod cuts out when the tripod is tilted > 15° and may indicate any dragging along the bottom and also possibly [indicate the] depth from bottom during raising and lowering.
Near bottom currents: EM Log
“Gaunt” Sphere carrying EM log and [equipped] with recorder (2 of 6 channels in use, depth limit 200m 1 2000m?). Record the 2 horizontal components of the current continuously for 4 minutes every hour for up to 8 hours.
[Recovery:] The corrosive bolts go first, then the explosive link is fired acoustically or by the back-up clockafter 15 hours from siting. Ultimately hoped to develop the instrument for measuring Reynolds stresses and turbulent fluctuations near the sea bed in great depths of water.
Photo Gallery: EM Log Sphere (during recovery)…