l%6 Toalih's SyJIem r effecting Changes of Weather. 



merit. For the fake of more certainty, however, M. To- 

 aldo compared a diary of the ftate of the barometer, kept 

 for many years, with the fituations of the moon, and found 

 the following remit : ift, ! hat the barometer at the time of 

 the moon's apogcum rifes the fixth part of a line higher than 

 at the perigeum ; 2d, that at the time of the quadratures it 

 (lands a tenth of a line higher than at the time of the fyzi- 

 gies; and 3d, that it is a fourth of a line higher at thefouth- 

 em hiriiftlce than the northern. 



Thus far the comparison of the moon's fituations with the 

 ftate of the barometer agrees perfectly with meteorological 

 obfervations. This, however, is not the cafe at the time of 

 the moon's paffage through her equinoctial points ; for the 

 heights of the barometer are then greater, chiefly when flie 

 paflfes in Libra: a circumftance which is contrary to meteo- 

 rological obfervations, fincejthefe fituations of the moon in- 

 dicate bad weather. It muft, however, be remarked, that 

 in this contradiction the indications of the moon's fituations 

 are more to be depended on than thofe of the barometer. 



It has a like connection with the coincidence of the equi- 

 noctial point and the perigeum, which alfo gives heights 

 confiderably greater. The union of thefe points, however, 

 is a fign of great irregularity. It muft here be remarked 

 that, according to De Luc, the rapid movement of the baro- 

 meter indicates a ftorm of fhort duration, and that in fuch a 

 cafe, even when it rifes, bad weather is likely to follow. 



M. Toaldo fays, -that the Europeans, when they firft vi- 

 fited Mexico, found a lingular cuftom prevalent in that 

 country. When a new emperor was chofen, he was obliged 

 to fwear that, during his government, rain fiiould fall ac- 

 cording to the pleafure of his fubjedts ; that no inundations 

 fhould be occafioned, and that the fields fhould not be ren- 

 dered unfruitful, &c. The multitude imagine that the me- 

 teorologift enters into an obligation of the like kind ; but all 

 that can be expected from him is confined merely to conjec- 

 tural rules refpecting changes of the weather; and even thefe 



prognoftics, 



