306 Progress of Foreign Science. 



may exist in one Number, we shall endeavour to supply in 

 another. 



I. Chemical Science. 



1. Principles of Combination. It gives us pleasure 

 to observe, that the accumulation of new facts in favour 

 of the chloridic theory first promulgated by Sir Humphry 

 Davy, has at length forced something like an assent to 

 its truth, from the ablest and most obstinate partisan of the 

 French oxymuriatic hypothesis. Professor Berzelius, after 

 waging a war of obscure and ineffectual words, like Priestley 

 with Phlogiston, against the English system, says, in his late 

 paper on the Sulpho-cyanides : " What I have just stated, both 

 on the cyanides in my preceding memoir, and on the sulpho- 

 cyanides in the present, proves that the phenomena relative to 

 these substances, caji admit of explanation only, on a theory 

 quite analogous to that which in these later times has been 

 adopted for the muriates, in considering oxymuriatic gas, as a 

 simple body-chlorine. This theory becomes more general and 

 at the same time more interesting, by extending it to all the 

 acids combined with water (hydrates), as well as to all the 

 salts, in the manner proposed by M. Dulong, by considering 

 the acids and the salts, as compounds of hydrogen and of metals 

 combined with the radical of the acid, and the oxygen both of 

 the acid and of the base, together forming one body." " The 

 decompositions and the recompositions of water, which I have 

 conjointly with other chemists, regarded as a great objection 

 against the new theory of the nature of muriatic acid, take 

 place with the sulpho-cyanides in a manner which leaves no 

 doubt of their reality ; and, we may add that the cyanides, and 

 especially the sulpho-cyanides, have a perfect analogy with 

 the salts formed by oxidized bases, and oxygenated acids ; that 

 is to say, formed by a combustible radical and oxygen*." 

 This Palinodia would have been better without the errors 

 tacked to it. The above view of the constitution of acids 

 and salts was given long ago by Sir H. Davy, as may be seen 

 in his paper, " On the analogies between the undecompounded 

 substances, and on the constitution of acids," published in the 

 first volume of this Journal. Thus ; " it is a simple statement 

 of facts to say, that liquid nitric acid is a compound of two 

 proportions of hydrogen, one of azote, and six of oxygen ; 

 and, as I shewed long ago the only difference between nitre 

 and hyperoxymuriate of potash is, that one contains a propor- 

 tion of azote, and the other a proportion of chlorine," p. 287. 

 And, with regard to these decompositions and recompositions, 

 they are mere fictions conjured up by himself and the late Dr. 

 Murray. Chlorine dislodges oxygen from potash, soda, lime, Sfc, 



* Annales de Chim. et de Physique, Tome XVI, pp. 35, 36, et 37. 



