210 On the Combination of Oxygen ivilh Water. [Sept. 



on the dry oxide produces a real explosion ; and so much heat 

 is evolved, that if the experiment be made in a dark place, there 

 is a very sensible disengagement of light. Besides the oxide of 

 silver, there are several other oxides, which act with violence on 

 oxygenated water ; for example, the peroxide of manganese, that 

 of cobalt, the oxides of lead, platinum, palladium, gold, iridium, 

 &c. Several metals in a state of extreme division occasion the 

 same phenomenon. I shall mention only silver, platinum, gold, 

 osmium, iridium, rhodium, palladium. In all the preceding 

 cases, it is always the oxygen united to the water which is disen- 

 gaged, and sometimes likewise that of the oxide ; but in others 

 a part of the oxygen unites with the metal itself. This is the 

 case when arsenic, molybdenum, tungsten, or selenium is 

 employed. These metals are often acidified even with the pro- 

 duction of light. 



I have had repeated opportunities of observing that the acids 

 render the oxygenated water more stable. Gold in a state of 

 extreme division acts with great force on pure oxygenated 

 water ; yet it has no action on that liquid if it be mixed with a 

 little sulphuric acid. 





Article IX. 

 Analyses of Books. 



Chemical Amusement, comprising a Series of curious and instruc- 

 tive Experiments in Chemistry, which are easily performed, 

 and unattended with Danger. By Frederick Accum, Opera- 

 tive Chemist. London, 1817. 



Notwithstanding the popularity of chemistry in this 

 country, and the great number of persons who are more or less 

 conversant with it, the individuals who have actually contributed 

 to its progress by the discoveiy of new facts, or the better 

 arrangement, or more satisfactory explanation of facts already 

 known, are but few. Were I to enumerate the names of all such 

 persons in every part of the world, it would occupy a much 

 smaller space than is generally supposed. Indeed the same 

 remark applies to all the sciences. It falls to the lot of a very 

 small number of individuals to eidarge the bounds of human 

 knowledge, or withdraw the veil which covers any portion of the 

 secret springs of nature. These individuals are led to those 

 pursuits, which redound so much to the dignity of man, and 

 ultimately tend so much to enlarge the sphere of his powers and 

 enjoyments, chiefly by the love of distinction, and by that eager 

 curiosity which animates and distinguishes generous minds. 

 But though the second of these principles might be sufficient, 

 perhaps, to stimulate the activity of the young mind in the 

 morning of life, when nature appears in her gayest colours, and 



