Intelligence and Miscellaneous Articles, 4-9 1 



crude material, wliicli is the blood, flows in the uninterrupted ves- 

 sels, and gives rise to all the different secretions ; such as milk, bile, 

 urine, &c., without the presence of any foreign body which could 

 form new combinations. 



Kirchoff discovered that starch dissolved in acids diluted with 

 water was converted at a certain temperature into gum and then 

 into sugar of grapes ; and yet there was no combination between 

 the elements of the acid and those of the starch, for no disengage- 

 ment of gas took place. On treating the solution with bases, all the 

 acid employed was regained ; the solution contained only sugar, 

 the weight of which only slightly exceeded that of the starch em- 

 plo3'ed. Some time afterwards, Thenard discovered a new sub- 

 stance, the binoxide of hydrogen, the elements of which are held 

 together by very slight affinity. This substance was not decom- 

 posed by acids, but alkalis gave its elements a^tendency to separate; 

 slow effervescence occurred with the disengagement of oxygen, and 

 water was formed. It was soon found not only that soluble sub- 

 stances produced this efll'ect, but also that other organic and inor- 

 ganic bodies, such as manganese, silver, platina, gold, fibrin, &c., 

 acted in the same manner upon it. This decomposition takes place 

 by the mere presence of the foreign body, in consequence of a 

 power which is at present unknown, and without the smallest quan- 

 tity entering into the new compound, for the most minute researches 

 failed in discovering the slightest alteration in it. 



Edmund Davy discovered that if extremely finely divided platina 

 be moistened with alcohol, this on taking fire ignites the platina, 

 and the alcohol, if it contains water, is converted into acetic acid. 

 This led to the grand discovery of Doebereiner, that spongy platina 

 has the property of firing a current of hydrogen directed upon it. 

 This discovery was soon followed by that of Dulong and Thenard, 

 who found that it was not platina alone that possessed this pro- 

 perty, but that other bodies, such as gold, silver, and glass, acted in 

 the same way, but only when they are exposed to a somewhat high 

 temperature ; whereas platina, iridium, and other metals which ac- 

 company platina, produce this effect even much below the tempera- 

 ture of melting ice. 



The analogy was observed which exists between the phsnoraena 

 of the conversion of sugar into alcohol by the presence of a foreign 

 insoluble body, and that of the decomposition of peroxide of hydro- 

 gen into water and oxygen, by the presence of platina, silver, fibrin, 

 and some other equally insoluble bodies. No case analogous to 

 that of the decomposition of binoxide of hydrogen by the presence 

 of the alkalis dissolved in this substance was known, for at this 

 period the analogy of this phaenomenon with that of the formation 

 of sugar by means of starch and sulphuric acid was not known. 

 Something similar occurs in one of the hypotheses on the formation 

 of aether. According to this hypothesis, sulphuric acid should com- 

 bine with one part of the water contained in the alcohol, and thus 

 would form aether ; but it could not be explained why other bodies, 

 such as potash, chloride of calcium, quickhme, &c., which have a 



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