Rain gauge which registers precipitation that is too light to be registered by ordinary recording of the depth of water from precipitation. Same as ombrometer.

A small, limited-capacity central processing unit contained entirely on one semiconductor chip.

Visible at magnifications above 25x.

A feeble oscillatory disturbance of the earth's crust, detectable only by very sensitive seismographs. Certain types of microseisms seem to be closely correlated with pressure disturbances. See microbarm.

The structure of a prepared surface of a metal as revealed by a microscope at a magnification exceeding 25x.

A red and white vertically striped buoy used in the United States to mark the middle of a channel. Midchannel buoys may be passed by on either side.

Shoal area between two navigational channels.

A non-commissioned naval rank. Midshipmen play a part, under supervision, in most of the ship's activities, and are in training for higher command.

In the middle portion of the boat - Roughly halfway between a ship's stem and stern, and where the beam usually is the widest.

Marine Industries Forum (EC)

Distance at sea is measured in nautical miles, which are about 6067.12 feet, 1.15 statute miles or exactly 1852 meters. Nautical miles have the unique property that a minute of latitude is equal to one nautical mile - Measurement of speed is done in knots ...

A unit equal to 5,280 feet on land. A nautical mile is 6076.115.

A common utility monetary measure equal to one-thousandth of a dollar or a tenth of a cent.

The heavy oxide layer formed during hot fabrication or heat treatment of metals.

A unit of pressure which directly expresses the force exerted by the atmosphere. Equal to 1000 dynes/cm2 or 100 pascals.

A unit used to measure the barometric pressure of the atmosphere. 1 millibar equals 0.03 inches of mercury.

A unit of atmospheric pressure equal to 1,000 dynes per sq. cm. or about 1/32 in. of mercury.

Marine Information Note

The most commonly used lubricating oil for compressors.

An intermodal system for transporting containers by ocean and then by rail or motor to a port previously served as an allwater move (e.g., Hong Kong to New York over Seattle).