Existence of Radicals in the Amphide Salts disproved. 61 
24. Now, if among the bodies above enumerated, some pairs 
of amphide and haloid salts can be selected, which make a tolera- 
ble match with respect to their properties, as in the case of sul- 
phate of soda, and chloride of sodium, while in other cases there 
is the greatest discordancy, (as in the stony silicate felspar, and 
the gaseous fluoride fluosilicic acid gas; as in soap and Derby- 
shire spar; as in marble and the fuming liquor of Libavius, the 
sour protochloride of tin, and sweet acetate of lead,) is it reason- 
able to found an argument in favor of a hypothetical similitude 
in composition, on the resemblance of the two classes in proper- 
ties? Does not the extreme dissimilitude in some cases, more 
than countervail the limited resemblance in others? And when 
the great variety of properties displayed both by the amphide 
and haloid salts is considered, is it a cause for wonder. or perplex- 
ity, that in some instances, amphide salts should be found to re- 
semble those of the other kind ? 
25. Again, admitting that there was any cause for perplexity 
agreeably to the old doctrine, is there less, agreeably to that 
which is now recommended? Is there no ground for wonder 
that oxygen or sulphur cannot act as simple halogen bodies? By 
what rule are their binary compounds to be excluded from the 
class of haloid salts? Wherefore should chlorides, bromides, 
iodides, and fluorides, however antisaline in their properties, be 
considered as salts, while in no case is an oxide, a sulphide, se- 
lenide or telluride to be deemed worthy of that name. 
26. I challenge any chemist to assign any good reason where- 
fore the red iodide of mercury is any more a salt than the red 
oxide, or the protochloride is more saline than the sulphide: or 
why the volatile oxides of osmium or of arsenic are less saline 
than horn silver or horn lead ; or the volatile chloride of arsenic, 
than the comparatively fixed sulphides of the same metal: why 
gaseous chlorohydric acid is more saline than steam or gaseous 
oxhydric acid. 
27. It much surprises me, that when so much stress is laid 
upon the idea of a salt, the impossibility of defining the mean- 
ing of the word escapes attention. How is a salt to be distin- 
guished from any other binary compound? When the discord- 
ant group of substances which have been enumerated under this 
name is contemplated, is it not evident that no definition of them 
