98 



PROGNOSTICS OP THE WEATHER, 



III. 



Letter from Dr. Beddoes on Prognojlics of the Weather, tlic 

 lilfirls of the Nitrous Oxide, and other Qbjecls. 



To Mr. NICHOLSON. 



Probability that 

 the enfuing 

 fpring and fum- 

 mer may prove 

 cold. 



How the wea- 

 ther is to be 

 foreknown. 



Conjecture. 



Atmofphcric 

 Currents of dif- 

 ferent tempera- 

 ture* 



SIR, 



Clifton, Jan. 9, 1 802. 



OINCE the late fall of fnow, I have been afked by feveral 

 people, how I would now apply the principle, dated in a 

 letter, inferted in one of your former Numbers *. My anfwer 

 was, that it induced me to fufpefi a correfponding great fall 

 in the N. and N. E. regions. If this be the fact, and if no 

 unknown calorific procefs take place between us and the 

 equator, it would furnifii an unfavourable prognoftic with re- 

 gard to the weather of the enfuing fpring and fummer. 



We can, I fufpect, only attain a degree of preference con- 

 cerning the feafons, by comparing the order of the moft ob- 

 vious meteorological events. Tin's, you know, was the way 

 in which the firft improvements were made in aflronomy. In 

 order to gain another point of comparifon, I beg leave diffi- 

 dently to propofe a conjecture, refpecting the duration of dif- 

 ferent falls of fnow\ The duration, I fuppofe, will bear fome 

 proportion to the quantity on the ground. For example, if an 

 inch of fnow fall, ivhen .the thermometer has been within the tzvdve 

 preceding hours above 32° it will either lie a much fhortcr time 

 than if fix inches fall, jo pt to lie under the fame condition. Per-- 

 haps the duration will generally be at leail equal to the fquares 

 of the depths. 



You will fuppofe that I found my conjecture upon fome 

 fort of reafoning. I deduced falls both of fnow and rain, after 

 Dr. Hutton, from the mixture of airs, unequally heated. 1 

 coniider fnow falling and lying in quantity, as the fign of a 

 great current of air from the polar regions, particularly when 

 the wind has blown for fome time from the oppolite points ; 



* Philof. Journal, Quarto V. 131. The principle is that, If there 

 be an unufualfall of fnow in the countries on thi N. and N. E. our 



fummer, ceteris paribus, will be cold and wet. 



that. 



