Dr. Vre's Chemical Dictloimnj. "»f) 



body so named affording the heat and hght. Of this position it 

 has been often remarked that we have no evidence whatever. 

 We know, on the otiior hand, that oxygen, the incombustible, 

 codd yield, from its latent stores, in Black's language, both the 

 light and heat displayed in combustion ; for mere mechanical 

 condensation of that gas, in a syringe, causes their disengagement* 

 A similar condensation of the coinbustible hydrogen, occasions, I 

 believe, tlie evolution of no light. From all these facts, it is 

 plain, that the above distinction is unphilosophical, and must be 

 abandoned. In truth, every insulated or simple body has sucii 

 an appetency to combine, or is solicited with such attractive 

 energy by other forms of matter, whether the actuating forces be 

 electro-attractive, or electrical, that the motion of the particles 

 constituting the change, if sufficiently rapid, may always produce 

 the phenomenon of comliustion, 



" Of the forty-nine resino-polar elements, forty-three are me- 

 tallic, and six non-metallic. 



*' The latter group niav be arranged into three pairs : — 



" 1st, The gaseous bodies. Hydrogen and Azote ; 



*' 2d, The fixed and infusil)le solids, Carbon and Boron ; 



*' 3d, The fusible and. volatile solids, Sulphur and Piiospiiorus. 



*' The forrv-three metallic bodies are distinguishable bv their 

 hnbi'u.les with oxygen, into two great divisions, the Rasifinble 

 and Acidifiable metals. The former are thiity-six in number, 

 the latter seven. 



" Of the thirty-six metals, which yield by their imioii vvith oxy- 

 gen salifialile bases, three are convertible into alk;dis, ten into 

 <?arths ■, and twenty-three into ordinary metallic oxides. Some 

 of the latter, however, by a niixinnmi dose of oxygen, seem to 

 graduate into the acidifiable group, or at least cease to forn> sa- 

 lifiable bases. 



*' We sliall now delineate a general chart of chctuistry, enu- 

 merating its various leading olijccts in a somewhat tabular form, 

 and pointing out tiieir most important relations, so that the 

 readers of this Dictionary may have it in tlieir power to study its 

 contents in a systematic order." 



" Acid AcKTic. The same i-.cid which, in a very dilute and 

 somewhat impure state, is called vinegju-. The varieiies of ace- 

 tic acids known in commerce ai'C four : Ist, wine vinegar; 2d, 

 malt vinegar ; .'id, sugar vinegar ; M\\, wood vinegiar, We shall 

 ■describe first the mode of makinu' these commercral articles, and 

 then that of extracting the absolute acetic acid of the chemiNt, 

 either from these vinegars, or directly fioiu thcmlcal compounds, 

 ot which it is a constituent. 



* 1 lure ro^^.'ird si;ir-ii ac.aiiij; as ii Itiise to fluxrif ncid, in tlif fluosilii-ic 

 «» npota I ; biit the subject is iiijbterions. bee ;\CU> (fl.'jOllic). 



Ji 2 "A crude 



