Natural History, 193 



times have given birth. The phenomenon of va- 

 pour becoming condensed, or of air in any manner 

 producing water, and fahing in the form of rain, 

 haily and snoWy has long been considered a point of 

 difficult solution among meteorologists. All the 

 suppositions to account for this fact v^ere, for a con- 

 siderable time, insufficient and unsatisfactory; and 

 even now the subject is far from being fully unfold- 

 ed. At one time the condensation and fall of va- 

 pour, in diffisrent forms, has been accounted for by 

 referring to the influence o^ Electricity ; at another, 

 by considering water as held in solution in air, and 

 precipitated, by streams of air of different tempe- 

 ratures being brought into contact, or a state of 

 mixture; and, at a third, by supposing this event 

 to be produced by the conversion of oxygen and 

 hydrogen gases into water, according to the ex- 

 periments of Cavendish, Lavoisier, and others. 

 These several opinions have been successively po- 

 pular in the course of the century, and will be 

 found amply detailed in the writings of Hamilton, 

 HuTTON, De SaussurEj and De Ll^c, on this sub- 

 ject. But, after all, it must be acknowledged, 

 that great difficulties attend every theory hitherto 

 formed with a view to solve this question. Inso- 

 much that the greatest meteorologist of the age, 

 M. De Luc, after making a more patient, accu- 

 rate, and thorough inquiry into the subject than 

 was ever accomplished by any other man, seems 

 to be at a loss to furnish a satisfactory account 

 of the matter. He therefore contents himself with 

 concluding, that the air, formed by the decompo- 

 sition and ascent of water, becomes reconverted 

 into that fluid, by some unknown cause, or by a 

 combination of causes, and fai)s in the form of 

 rain, hail, or snow, according to the circumstances 

 in which th^ reconversion takes place, or the state 



