Chapter XII

WINDS. _Observe, that in eight Years' Time there is as much South
West Wind, as North East, and consequently as many wet Years
as dry._

THIS must be allowed a very extraordinary Aphorism from a Country Shepherd, but at the same Time it is very agreeable to the Observations of Dr. _Hooke_, Dr. _Derham_, Dr. _Grew_, and other able Naturalists, who with unwearied Pains and Diligence have calculated the Quantity of Rain falling in one Year, and compared it with what fell in another. Lord _Bacon_, that Honour to our Nation and the Age which produced him, informs us, that it was an old Opinion there was a total Revolution of the Weather once in forty Years, and wishes it was inquired into. I cannot tell whether this has ever been done or not, but I think there is good Reason to conclude that there is a natural Balance established of wet and dry Weather, as of Light and Darkness, Heat and Cold, and other such like Variations.

IT may not be amiss to caution the Reader against a Mistake into which the Manner of this Rule being stated may easily lead him. It is this, that South West Winds cause Rain, and North East Winds fair Weather, which however is not a Thing clear or certain by any means. This indeed is true, that South West Winds and Rain, North East Winds and fair Weather come together, generally speaking. But the Question is, which causes the other, and a more difficult Question cannot easily be stated, because there seems to be Facts on both sides. South West Winds seldom continue long without Rain, this seems to prove the affirmative, but on the other Hand, when in hard Weather, Rain begins to fall, the Wind commonly veers to the South West, this looks as if the Rain caused the Wind.

BUT to keep close to the Shepherd's Observation. There is one Thing seems strongly to confirm it, which is this, that in any given Place the Quantity of Rain one Year with another is found to be the same by Experience, according to which the following Table has been calculated, for the mean Quantity of Rain falling one Year with another in those Places that are mentioned, and on this Proportion the other seems to be founded.

At Harlem 24 Inches
Delf 27
Dort 40
Middleburg 33
Paris 20
Lyons 37
Rome 20
Padua 37-1/2
Pisa 34-1/4
Ulm 27
Berlin 19-1/2
In Lancashire 40
Essex 19-1/2