1820.1 



the Atomic Theory. - 345 



r + \ oxygen = Oxide 



\ + 2 sulphur = Sulpliuret 



Silver, 13*71 < +4 4 chlorine. . = Chloruret 



(I + 15-62 iodine .= loduret 



? + 1 oxvgen . .. . = Oxide 

 Palladium, 8-333 ^ +2 sulphur . . . . = Sulphuret 



( + 4-4 chlorine . . = Cliloruret 



f + \ oxygen = Protoxide 



\^2 = Deucoxide 



Gold, 24-96 "\ +4 sulphur = Deulosulphiiret 



r +8-8 ciilorine..= Dcutochloruret 



f + 1 oxvgen = Protoxide 



Platinum, S3-625 3+2...'. = Oeutoxide 



/ +8-8 chlorine.. = Deulochloruret 



Iridium, 6 +2 sulphur . . . . = Sulphuret 



The weight of each inflammable substance in this table is in 

 general such, that in miiting to one part of oxygen, it passes to 

 the first deo-ree of oxidation. But the rule has been departed 

 from in regard to phosphorus, sulphur, iodine, arsenic, mo- 

 lybdenum, chromium, tungsten. For each of these the repre- 

 sentative number is taken from such a weight of its acid as can 

 saturate a base containing one part of oxygen. This renders the 

 table more short and convenient, because it leaves nothing to do 

 except adding the number that represents the weight of an acid 

 (found in the table) to the number representing any base what- 

 ever (found also in the table) in order to get the proportions ot 



all the salts. . ^ c ^ v. 



For example, by adding 5 sulphuric acid, or 4 ot sulphurous 

 acid to 3-62 hme, we get the sulphate or the sulphite of lime. 



Dr. Wollaston has made an arrangement of proportional num- 

 bers, which he calls a synoptic scale of chemical equivalents, that 

 exhibits in a very condensed form the constituents of a great 

 many compound bodies. 



When a chemist subjects a saline substance to analysis, the 

 questions to be answered are so many and various, that he is 

 seldom disposed to undertake, by himself, the necessary series 

 of experiments, if he can rely with confidence on the labours of 



his predecessors. i • ^ r 



Let the crystaUized sulphate of copper be the subject of ana- 

 lysis, and the questions to be resolved are these. How much 

 does it contain of sulphuric acid? How much oxide of copper? 

 How much water ? We may wish to know further the quantity 

 of sulphur, of copper, of oxygen, of hydrogen. , . ,, 



It may be necessary to consider, likewise, how much ot the 

 different reagents must be employed to discover the proportion 

 of sulphuric acid ; for instance, how much barytes, carbonate of 

 barytes, or nitrate of barytes ; or how much lead in the form ot 

 nitrate. And after having obtained the precipitates of sulphate 

 of barytes and sulphate of lead, it is still necessary to find the 

 proportion of dry sulphuric acid which they respectively hold. 

 We may wish to verify these results by ascertaining the pre- 



