REPORT ON CHEMISTRY. 
441 
when they combine with other bodies. These are oxygen, 
sulphur, selenium and tellurium, and are called acid-and-base 
formers. 
3rd, Such as possess neither of these properties, but which 
with bodies of the second class form acids. These are azote, 
hydrogen, phosphorus, boron, carbon, silicon, arsenic, and the 
electro-negative metals. 
He then proceeds to describe the preparation and properties 
of a vast number of compounds of sulphur with the simple 
bodies, in which he demonstrates the striking analogy between 
that substance and oxygen, and shows— 
1°, That sulphur gives a numerous and interesting class of 
salts in which the oxygen in the oxygen salts is replaced by an 
equal number of atoms of sulphur, and that this exchange 
in many oxygen salts may be effected by a current of sul¬ 
phuretted hydrogen, the hydrogen of which combines with the 
oxygen both of the acid and the base, and the sulphur takes 
its place. 
2°, That many of these salts, and generally all those of the 
metals which form with oxygen alkalies or alkaline earths, dis¬ 
solve in water, crystallize, combine with water of crystallization, 
unite with one another and with oxygen salts to form double 
salts, exhibit different degrees of saturation, and in these follow 
the same multiples as the oxygen salts. 
3°, That the sulphur salts are formed in such proportions as 
generally to have corresponding oxygen salts, but that several 
classes of sulphur salts have been obtained, the oxygen salts 
corresponding to which are as yet unknown. Thus, for example, 
he formed three sulphur acids of arsenic, two of molybdenum, 
three of antimony, and one of tin, while of arsenic we know r only 
two oxygen acids, and of molybdenum one. Considerable ob¬ 
scurity still attaches to the compounds of oxygen and tin. 
4°, That the radicals of all the oxygen acids do not give 
sulphur acids, or at least that they have not yet been formed. 
Thus with chlorine, iodine, bromine, fluorine, azote, boron, 
silicon, titanium and selenium, he could form no sulphur acids 
or salts. The compound radicals of the organic acids are in 
the same condition, though a mode of replacing their oxygen 
by sulphur may yet be discovered. 
5°, Negative or acid combinations of sulphur (and consequent 
classes of sulphur salts,) were formed with hydrogen, carbon, 
phosphorus, arsenic, molybdenum, tungsten, tellurium, anti¬ 
mony, tin; and less distinct ones with chromium, tantalum, gold, 
platinum, rhodium, and probably some other metals. 
