Appendix 287

INDEX 293

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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