206 Rev. J. B. Enunett on an Anomaly presented by [Sept. 



nienon. According to the tables in Brande's Chemistry, which 

 seem to be generally very exact, the atomic weight of oxygen is 

 7*5; the atom of potassium is 37'5 ; its specific gravity "85. 

 Protoxide of potash, by the combustion of potassium m dry 

 oxygen is 45, and its specific gravity is 2"5. Now the volume 



,. , , its weight 



of a oody = -. — . 



J its sp. gv. 



Therefore the volume of an atom of potassium = '-— - = 44T 1 , 



and the volume of an atom of dry potash = ^— = 18. 



The volume occupied by the atom of oxygen in this compound 

 = volume of potash — volume of potassium = 18 — 44-11 = 

 — 26' 11 ; so that 37*5 parts by weight of potassium occupy a 

 volume which may be represented by 44*11 ; by combustion, it 

 combines with 7*5 parts by weight of oxygen, and the volume 

 becomes 18 ; consequently the space occupied by the oxygen is 

 negative, i. e. 26*1 1 of space less than 0, which is absurd. Since 

 the above numbers are the result of the most careful experi- 

 ments, the subject is of great importance, inasmuch as it is a 

 singular anomaly, and intimately connected with the first princi- 

 ples of chemical philosophy. If the particles of all solids be at 

 all times in contact with each other, as I have supposed in all 

 my former papers, so extraordinary an effect cannot result from 

 any known property of combination ; for (as I have proved in a 

 former paper; if a solid be heated to its fusing point, and its 

 temperature next reduced to the true zero, the utmost possible 

 diminution is ± of the original volume; or volume at the melting 

 point : volume at zero :: 1 : -| ; and in the combination of bodies, 

 unless their atoms be very unequal, no diminution greater than 

 this can be produced. Therefore on this principle the effect 

 cannot be produced. 



By the generally received hypothesis, that the particles of 

 solids are never in contact with each other, the phenomenon 

 may appear to be accounted for • for since the attraction between 

 the two bodies is evidently very powerful, a great diminution of 

 volume may be supposed to take place, since there is no limit to 

 that which may take place, except the distance between the 

 particles, which some philosophers have supposed to be extrava- 

 gantly large. But here arises a great difficulty : suppose the 

 force of attraction to vary according to any assumed law, the 

 simplest investigation will show that there can be no force of 

 cohesion, unless the particles of the solid actually touch each 

 other ; that is, it is only in contact that the particles can be 

 powerfully urged together by a force, which is indefinitely dimi- 

 nished, when the distance between their centers is increased by 

 any indefinitely small quantity. This hypothesis then being 

 opposed to every known principle of philosophy is untenable. 



