Meteorology^ 249 



Cotte has prefentecl a view of the fevere winters which 

 v^-e have experienced. A difpuie had arifen among the fci- 

 entific men at Paris refpefting the cold which would take 

 place in the winter of the year 1798 : and fome afferted that 

 it would he fevere becaufe that of 1398 was fo ; founding 

 their opinion on this circumftance, that the fame temperature 

 muft take place every four hundred years. Mazuyer main- 

 tained, that the fevere winters in our climates take place be- 

 tween the fourth and fifth year, or the eighth and ninth 

 years ; becaufe, according to the remark of Toaldo, the fea- 

 fons and conftitution of the years mu.l have a period almoft 

 equal to the revolution of the lunar apogcum, which is from 

 eight to nine years, and that, towards ihe middle of thia 

 period, that is to fay, every four or five years, tiiere mufl: be 

 a return. Thus the fevere winter of 1788-1789 followed 

 one which took place ten years before; and that of 1794- 

 1795 took place four years after that of 1788-1789. 



Cotte feems rather to refer to the period of nineteen years, 

 which brings back the moon to the fame points. He efti- 

 mates, therefore, that the general temperature of any year , 

 ought to correfpond with that of each antecedent nineteenth 

 year after the commencement of the century. But thefc; rules 

 he confidcrs only as probabilities, 



Lamarck has publiflied an annuary, in which he endea- 

 vours to determine a prognoftication of the temperature froni 

 the pofition of the moon in the louthern or northern figns. 

 When {lie is in the fouthcrn, it is probable that north and 

 caft \\ luds will prevail ; when Hie is in the northern, it is 

 probable that fouth and eafl winds will be moft prevalent ; 

 and thcfe winds have a decided influence on the temperature 

 and rain *, 



Cotte has given an extract of a memoir, by Beaume, on 

 thermometers. The motion of thofe made with fpirit of wine 

 is different from thofe made with mercury. Thus, near the 

 degree of boiling water, when the mercurial thermometer 

 falls five degrees, that made with fpirit of wine falls fevcn ; 

 and on the other hand, near the freezing point, when th(j 

 mercurial thermometer falls five degrees, that made with 

 <♦ Sec alio Toaklo's p.ipcr on this fubjea, Phil. M.ig. Vol. IV. p. ^67. 



VoL.Vr. Kk fpiiit 



