Page:Small-boat sailing; an explanation of the management of small yachts, half-decked and open sailing-boats of various rigs; sailing on sea and on river; cruising, etc (IA smallboatsailing01knig).pdf/236

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temperature, will cause the barometer to rise. Thus it is that the glass falls lowest with the rainy warm south-westerly winds; and rises highest with winds from the north-east, which are both cold and dry. Thus, too, if the barometer falls considerably, while the thermometer indicates a low temperature for the time of the year, the wind will probably come from a northerly direction; whereas, if the barometer is falling, with the temperature of the air high for the time of the year, southerly winds may be expected.

With the degree of moisture, the temperature of the air and the direction of the wind remaining unchanged, a fall of the glass indicates an increase of the force of the wind from the same direction.

These are Admiral Fitzroy's two general rules for barometer readings in our latitudes:—

The barometer rises for northerly wind (including from N.W. by the N. to E.), for dry or less wet weather, for less wind, or for more than one of these changes; except on a few occasions, when rain or snow comes from the north, with strong wind.

The barometer falls for south wind (including from S.E. by the S. to W.), for wet weather, for stronger wind, or for more than one of these changes, except on a few occasions, when moderate wind, with rain or snow, comes from the northward.

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