USEFUL MEMORANDA.

One statute mile is 5280 feet.
One nautical mile is 6086 feet = 1¹⁄₆ statute mile.
A knot is a speed of 1 nautical mile per hour.
Hence the following rules:⁠—
To convert
Knots to miles per hour—multiply by 1¹⁄₆.
Miles per hour to knots—multiply by ⁶⁄₇.
Feet per second to miles per hour—multiply by ²⁄₃. ⁄
Feet per second to knots—multiply by ⁶⁄₁₀.
Knots to feet per minute—multiply by 100.

WAVES AND RIPPLES IN WATER,
AIR, AND ÆTHER.

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