LAUGEL'S PROBLEMS OF NATURE AND LIFE. 339 



In mentioning this law first distinctly stated by 

 Leibnitz, but verified and largely amplified since we 

 may again briefly advert to the recent experiments of 

 Dr. Andrews, annulling the old view that the solid, 

 liquid, and gaseous forms are severally assumed per 

 saltum^ and proving a continuous and gradual change 

 from one of these states to another, subject to condi- 

 tions of heat and pressure. These researches we re- 

 gard as highly important ; not solely in relation to the 

 theory of gaseous bodies, but also to the doctrines of 

 heat, and generally to all phenomena in which atomic 

 actions are concerned. 



We cannot close this short sketch of the state of 

 chemical science without 'ad verting to one great hiatus 

 (valde deflendus, we may add) in this great depart- 

 ment of knowledge ; the want, namely, of some single 

 system of chemistry, which, basing its classification 

 and nomenclature on philosophical theory, may give 

 true relation and congruity to facts now become ap- 

 palling from their multitude and various interpretation. 

 We have before us at this moment four several volumes, 

 the works of chemists of high and merited eminence, 

 each adopting and carrying into details its own special 

 principles of arrangement and nomenclature. In some 

 cases these differences involve cardinal points of chemi- 

 cal theory. In all cases they are embarrassing to the 

 student ; and very especially so in organic chemistry, 

 the newest and most arduous department of the science. 

 Still, we can hardly feel surprise at the deficiency we 

 state, seeing the enormous complexities of the subject; 

 augmenting rather than diminishing with the disco- 



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