114 On the Daltonian Theory of [Aug. 



1. Oxygen 1 



2. Sulphur 2 



3. Potassium 5 



4. Arsenic 6 



5. Copper S 



6. Tungsten 8 



7. Uranium , IS- 



8. Mercury 25 



3. An atom of phosphorus is ten times as heavy as an atom 

 of hydrogen. None of the other atoms appear to be multiples 

 of 0*132 ; so that if we pitch upon hydrogen for our unit, the 

 weight of all the atoms will be fractional quantities, except that 

 of phosphorus alone. 



4. It is quite clear that neither hydrogen nor azote contain 

 any oxygen ; for as the weight of an atom of each of these 

 bodies is less than the weight of an atom of oxygen, it is im- 

 possible that oxygen can enter into their composition. Hence 

 the whole doctrine respecting ammonium, and the supposition 

 that hydrogen and azote are oxides of ammonium — a supposition 

 countenanced at first by Davy, and still supported by Berzelius, 

 must be erroneous. For the same reason, Berzelius' notion that 

 azote is a compound of oxygen and an unknown combustible gas, 

 cannot be admitted. 



5. The weight of an atom of the metals being high, when 

 compared with that of oxygen, or the simple combustibles, they 

 may be, and probably are, compounds ; though, from their peculiar 

 properties, they may long elude all our methods of decomposi- 

 tion. Their conducting power is too perfect to enable us to hope 

 for any decomposition from the action of the galvanic battery, 

 however powerful. 



6. We have it now in our power to compare the law laid down 

 by Berzelius ; namely, that the weight of the sulphur in a 

 metallic sulphuret is double that of the oxygen in the oxide of 

 the same metal, with the truth. We shall find it to hold in all 

 the sulphurets hitherto examined, except those of nickel, cobalt, 

 and tellurium. The following table exhibits the particular oxides 

 and sulphurets that have this relation to each other : — 



Oxides. Corresponding Sulpburets. 



Peroxide of gold Sulphuret of gold. 



Peroxide of platinum Sulphuret of platinum. 



Oxide of silver Sulphuret of silver. 



Protoxide of mercury Prosulphuret of mercury. 



Peroxide of mercury Persulphuret of mercury. 



Protoxide of copper .......... .Sulphuret of copper. 



