324 NOVUM ORGANUM. 



cum sibilo), aquam traxit ad tale quantum quale sufficere 

 posset ad hoc, ut aer antiquam recuperaret sphaeram sive di- 

 mensionem. 1 



Atque certum est corpora tenuiora (quale est aer) pati con- 

 tractionem nonnullam notabilem, ut dictum est; at corpora 

 tangibilia (quale est aqua) multo aegrius et ad minus spatium 

 patiuntur compressionem. Qualem autem patiatur, tali experi- 

 mento inquisivimus. 



Fieri fecimus globum ex plumbo cavum, qui duas circiter 

 pintas vinarias contineret ; eumque satis per latera crassum, ut 

 majorem vim sustineret. In ilium aquam immisimus, per fora- 

 men alicubi factum ; atque foramen illud, postquam globus 

 aqua impletus fuisset, plumbo liquefacto obturavimus, ut globus 

 deveniret plane consolidatus. Dein globum forti malleo ad duo 

 latera adversa complanavimus ; ex quo necesse fuit aquam in 

 minus contrahi, cum sphaera figurarum sit capacis?ima. Deinde, 

 cum malleatio non amplius sufficeret, segrius se recipiente aqua, 

 molendino 2 seu torculari usi sumus; ut tandem aqua, impatiens 

 pressure ulterioris, per solida plumbi (instar roris delicati) ex- 

 stillaret. Postea, quantum spatii per earn compressionem im- 

 minutum foret computavimus ; atque tantam compressionem 

 passam esse aquam (sed violentia magna subactam) intellexi- 

 mus. a 



1 This explanation is wholly unsatisfactory. The principle upon which the true 

 explanation depends, namely the pressure of the atmosphere, was, it seems tolerably 

 certain, first suggested by Torricelli. If the experiment were performed in vacuo, no 

 water would enter the egg, unless the egg were plunged to a considerable depth into 

 the water, or unless the vacuum within it were more perfect than could be produced 

 in the manner described. 



2 Molendinum is properly a Low Latin word for a mill-house ; here used for a 

 press. 



1 This is perhaps the most remarkable of Bacon's experiments ; and it is singular 

 that it was so little spoken of by subsequent writers. Nearly fifty years after the 

 publication of the Novum Organum, an account of a similar experiment was published 

 by Megalotti, who was secretary of the Accademia del Cimento at Florence ; and it has 

 since been familiarly known as the Florentine experiment. I quote his account of it. 

 " Facemmo lavorar di getto una grande ma sottil palla d' argento, e quella ripiena 

 d' acqua raffreddata col ghiaccio serramo con saldissime vite. Di poi cominciammo 

 a martellarla leggiermente per ogni verso, onde ammaccato 1' argento (il quale per la sua 

 crudezza non comporta d* assottigliarsi e distendersi come farebbe 1' oro raffinato, o il 

 piombo, o altro metallo piu dolce) veniva a ristrignersi, e scemare la sua interna capa- 

 cita, senza che 1' acqua patisse una minima compressione, poiche ad ogni colpo si videa 

 trasudarfe per tutti i pori del metallo a guisa d' argento vivo il quale da alcuna pelle 

 premuto minutamente sprizzasse." Saggi di naturali Esperienze fatte neW Accademia 

 del Cimento, p. 204. Firenze, 1667. The writer goes on to remark that the absolute 

 incompressibility of water is not proved by this experiment, but merely that it is not 

 to be compressed in the manner described. But the experiment is on other grounds 

 inconclusive. 



It is to be remarked that Leibnitz, Nouveaux Etsais, in mentioning the Florentine 



