24-8 Principles on which Clouds arc suspended. 



far from being any thing approaching to a solution of the 

 enquiry, How are clouds suspended? I will just mention 

 one or two of those conjectures before I offer my own remarks. 

 De Luc supposes that each particle of the vesicular vapour 

 which constitutes clouds contains a small portion of hydrogen 

 gas ; and this gas, he says, enables the particles, like so many- 

 little air-balloons, to remain suspended in the atmosphere at 

 different elevations. This same naturalist also conceives, not 

 proves, that this hydrogen gas is derived from a supposed de- 

 composition of a portion of the water itself. He, therefore, 

 gives no explanation of the cause, or proof of the effect. Now, 

 it appears to me, and I think it will appear plain to every care* 

 ful observer of nature, that, if this theory of De Luc had been 

 founded on actual observation, the presence of this hydrogen 

 gas would have been detected, either on the summits of " cloud- 

 capt " mountains, or, indeed, in any other place in a foggy 

 atmosphere ; but I am not aware of any meteorologist ever 

 yet having made such a discovery. 



I have perused the theory of Mr. Luke Howard on this 

 portion of meteorology with no better success. Howard sup- 

 poses each particle of vesicular vapour to be " similarly elec- 

 trified," and that, consequently, they "repel each other." Now, 

 admitting this repelling property to retard condensation, which 

 it would have a tendency to do, it would not prevent the de- 

 scent of the vesicles; for each globule of water, how minute 

 soever it might be, would be heavier than the circumambient 

 air, and, consequently, would, by the force of gravity, fall to 

 the earth, although with a less velocity than a considerable 

 volume of the same fluid. I, therefore, do not consider the 

 suspension of clouds to be at all accounted for by either of 

 these hypotheses ; nor do I know of any other that claims 

 superior attention. 



How distinguished soever for learning and science may 

 have been our predecessors, we are not bound to show them 

 deference, by blindly embracing their opinions ; for the very 

 spirit which carried them to a certain extent of knowledge in 

 their days would, could they revisit this 



" Poor pitiable speck our earth," 



and renew their studies under all the advantages which they 

 themselves so ably contributed to produce, carry them onward 

 to greater improvements, and to the rejection of many erro- 

 neous opinions they formerly entertained. We live in a world 

 surrounded by objects of high interest, whose influence has 

 great effect on our existence and comfort, and whose varied 

 impressions strike our senses with wonder and astonishment. 



