154 Prognostics of the Weather. 



cause is obvious : the atmosphere is replete with vapours, 

 which, though sufficient to reflect and intercept the sun's 

 rays from us, yet want density to descend ; and while the 

 vapours continue in the same state, the weather will do 

 so too. 



Accordingly, such weather is generally attended with 

 moderate warmth, and with little or no wind to disturb the 

 vapours, and a heavy atmosphere to sustain them, the 

 barometer being commonly high. But when the cold ap- 

 proaches, and by condensing drives the vapours into clouds 

 or drops, then way is made for the sunbeams ; till the same 

 vapours begin, by further condensation, to be formed into 

 rain, and fall down in drops. 



2. "A change in the warmth of the weather is generally 

 followed by a change in the wind." Thus, the northerly 

 and southerly winds, commonly esteemed the cause of cold 

 and warm weather, are really the effects of the cold or 

 warmth of the atmosphere, of which Mr. Derham assures us 

 he has had so many confirmations, that he makes no doubt 

 of it. Thus it is common to see a warm southerly wind 

 suddenly changed to the north, by fall of snow or hail ; or 

 to see the wind in a cold frosty morning north, when the 

 sun has well warmed the earth and air, wheel towards 

 the south ; and again turn northerly and easterly in a cold 

 evening. 



3. " Most vegetables expand their flowers and down in 

 sunshiny weather, and towards the evening; and against 

 rain close them again," especially at the beginning of their 

 flowering, when their seeds are tender and sensitive. This 

 is visible enough in the down of the dandelion, and other 

 downs ; and eminently in the flowers of the pimpernel, the 

 opening and shutting of which, Gerard observes, are the 

 countryman's weather-wiser, whereby he tells the weather 

 of the following day. The rule is, if the flowers are close 

 shut up, it betokens rain and foul weather; if they are 

 spread abroad, fair weather, (Ger. Herb. lib. 2.) 



" Est et alia (arbor in Tylis) similis, foliosa tamen, ro- 

 seique floris qua noctu comprimens aperire incipit solis 



