100 On Chemical Equivalents. 



cles of oxygen to saturate it. Were this the case, water, or 

 its constituents, might be obtained in an intermediate state of 

 combination, Hke those of sulphur and oxygen, or azote and oxy- 

 gen, &c. This appears to be impossible ; for in whatever pro- 

 portion we mix hydrogen or oxygen gases, or under whatever 

 eircumstances we unite them, the result is invariably the same. 

 Water is formed, v.wA the surplus of either of the gases is left 

 behind unchanged." — " From these circumstances, we have suf- 

 ficient reason to conclude, that water is composed of a single 

 ultimate particle of oxygen, and an ultimate particle of hydro- 

 gen, and that its atoms are incapable of uniting to a third parti- 

 cle of either of its constituents." 



Mr. Iliggins inculcates very strongly, that when a body is 

 capable of combining with another in two proportions, the third 

 particle introduced is held by a much weaker affinity than that 

 which unites the particles of the first or true binary compound. 



" In my opinion, the most perfect nitrous acid contains 5 of 

 oxygen and 1 of azote. Nitrous gas, according to Kirvvan, con- 

 tains 2 volumes of oxygen gas, and 1 of azotic gas. According 

 to Lavoisier, 100 grains of nitrous gas contain 32 grains of 

 azote, and 68 of oxygen. 1 am of the former philosopher's opi- 

 nion. 1 also am of opinion, that every primarv particle of azote 

 is united to 2 of oxygen, and that the molecule thus formed, is 

 surrounded with one common atmosphere of caloric. 



" As this requires demonstration, let A in the annexed dia- 

 gram represent an ultimate particle of azote, which attracts oxy- 

 gen with the foice of 3 ; 



.3 6 3 



A— a 



Let « be a particle of oxygen, whose attraction to A we will sup- 

 pose to be 3 more; hence they will unite with the force of 6; 

 the nature of this compound will be hereafter explained. Let 

 us consider this to be the utmost force of attraction that can sub- 

 sist between oxygen and azote. We will now suppose a second 

 particle of oxygen h to combine with A; they will only unite 

 with the force of 4\." " This I consider to be the real struc- 

 ture of a molecule of nitrous gas. Let a third particle of oxy- 

 gen c unite to A, it will combine only with the foree of 4. This 

 is the state of the red molecules of nitrous vapour, or when con- 

 densed, the red nitrous acid." "We will suppose a fourth par- 

 ticle of oxygen d to combine with A ; it will unite with the force 

 of 3|, and so on with tlie rest of the particles of oxygen as the 

 diagram represents. This I consider to be the state of a molecule 

 of the pale or straw-coloured njtrous acid." 



"When a fifth particle of oxygen e unites, tlie force of union 

 pxisting between the particles of the molecule h< still diminished 



as 



