506 Rev.W.V. Harcourt on Lord Brougham's statements 



various experiments concluded, that the substance itself of 

 the globule, from which air was produced in them, is changed 

 into an 'aura,' as water is changed into vapour by heat: but 

 unlike vapour, this aura remains aura, and as he himself 

 proves by experiment, retains its elastic force. Does there 

 exist then any other body besides air which is fluid and en- 

 dowed with elastic force? I scarcely believe it. He alleges 

 indeed as a reason for denying to this aura the nature of com- 

 mon air, that he has found by experiment that the said aura 

 is incapable of supporting life: as if, because it does not sup- 

 port life, therefore it cannot be air ! we see our atmospheric 

 air itself in time of pestilence unfitted to support life : has it 

 therefore ceased to be air ? it would be absurd to say this. It 

 is not to be denied that in the space E. H. [of a glass tube 

 filled with carbonic gas] other particles besides air find room, 

 separated perhaps by the impetuous motion of the efferves- 

 cence from the acid liquor, or the solid globule, and carried 



poribus, sed et alterum nobis ostendendum est, nimirum quod aer iste sit 

 aere naturalis consistentiae densior. Hoc auteni sequenti experimento de- 

 monstratur. Sumatur vasciilum liquore quodam acido semiplenum, ut A. 

 C. D. B., et tubus aliquis vitreus E. F., altera parte E. clausus, altera vero F. 

 apertus, impleatur eodem liquore; hujus vero orificio F. induatur globulus 

 G., de lu to, vel creta, in quibus nempe multae particulae alkali insunt, con- 

 fectus; statimque, indice super orificium F. posito, invertatur tubus,- et li- 

 quori in vasculo contento immergatur orificium F. ; amoto digito, mox ob- 

 servabitur magnam efterveseentiam excitari, quae per aliquot horas durabit, 

 donee omnis aer, intra particulas alkali contentus, solutis vinculis quibus 

 coarctabatur, ad superiora aseenderit, et materia subsedei it; turn demum 

 animadvertitur, aerem hunc, postquam despumaverit, in suprema parte de- 

 presso liquore, magnum spatium E.H. occupare: quandoquidem auteni su- 

 perficies H. liquoris in tubo altior est superficie liquoris in vasculo, erit aer 

 in spatio E. H. contentus aliquantulum rarior aere externo ; proinde, ut fiat 

 ejusdem consistentiae, opus est ut aut tubus altius immergatur, ant plus li- 

 quoris afTundatur, donee superficies interna eoincidat cum superficie exte- 

 nori; quo facto, erit quidem spatium E. H. priori patilulum contractius, et 

 aer in eo contentus naturalis consistentiae : nihilo minus tamen adhuc ma- 

 jus erit, duplo, triplo, quadruplo, (pro diversitate materiae terrestris ex qua 

 globulus conficitur, qua scilicet plus vel minus particularum alkali in se con- 

 tinet,) quam quod tota moles globuli G. occupat ; quod certum indicium est 

 aerem istum, cum omnis adhuc in globo continebatur, nuilto densiorem 

 fuisse quam aer externus est: posito enim globulum constare, ex una parte, 

 materiae. terrestris, et ex una parte, pororum, quibus nempe aer condensa- 

 tus inest, — vel, quod eodem recidit, spatium quod materia terrestris occu- 

 pat esse aequale spatio quod aer in poris contentus replet, — si nunc spatium 

 E. H. sit duplum spatii globuli totins, sequitur, aerem in globulo ccntentum 

 quadruplo densiorem esse quam est aer externus, si triplum sextuplo, si 

 quadruplum octuplo, et sic porro in subdupla ratione ; si vero ponatur spa- 

 tium materiae terrestris non esse aequale spatio pororum, sed in alia ratione 

 majoris vel minoris inasqualitatis, densitates ae'ris in globulo aeque facile ad 

 calculum revocari possunt." — Bernoulli, Dis&ertatio de Effervescentia et Fer- 

 mentalione, No. 1. p. 20. 1690. 



