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Brahmah's press, are also demonstrable as conclusions from the 

 same theory. 



Conceive a continuous mass of ice, with vesicles containing either 

 air or water distributed through it ; and let this mass be pressed 

 together by opposing forces on two opposite sides of it. The vesi- 

 cles will gradually become arranged in strata perpendicular to the 

 lines of pressure, because of the melting of ice in the localities of 

 greatest pressure and the regelation of the water in the localities of 

 least pressure, in the neighbourhood of groups of these cavities. For, 

 any two vesicles nearly in the direction of the condensation will 

 afford to the ice between them a relief from pressure, and will occa- 

 sion an aggravated pressure in the ice round each of them in the 

 places farthest out from the line joining their centres ; while the 

 pressure in the ice on the far sides of the two vesicles will be some- 

 what diminished from what it would be were their cavities filled up 

 with the solid, although not nearly as much diminished as it is in 

 the ice between the two. Hence, as demonstrated by my brother's 

 theory and my own experiment, the melting temperature of the ice 

 round each vesicle will be highest on its side nearest to the other 

 vesicle, and lowest in the localities on the whole farthest from 

 the line joining the centres. Therefore, ice will melt from these 

 last-mentioned localities, and, if each vesicle have water in it, the 

 partition between the two will thicken by freezing on each side of it. 

 Any two vesicles, on the other hand, which are nearly in a line per- 

 pendicular to the direction of pressure will agree in leaving an aggra- 

 vated pressure to be borne by the solid between them, and will each 

 direct away some of the pressure from the portions of the solid next 

 itself on the two sides farthest from the plane through the centres, 

 perpendicular to the line of pressure. This will give rise to an in- 

 crease of pressure on the whole in the solid all round the two cavi- 

 ties, and nearly in the plane perpendicular to the pressure, although 

 nowhere else so much as in the part between them. Hence these 

 two vesicles will gradually extend towards one another by the melt- 

 ing of the intervening ice, and each will become flattened in towards 

 the plane through the centres perpendicular to the direction of press- 

 ure, by the freezing of water on the parts of the bounding surface 

 farthest from this plane. It may be similarly shown that two vesi- 

 cles in a line oblique to that of condensation will give rise to such 



