4U 



MISTRY. 



[ACBTIO ACID CTHKM. 



I ; 



rMe; bnt, gmmUy spcakine, oil of turpentine 

 oly sutMtitutod, and fence arise some highly IT 

 iatel ffsote on the intern of the habitual gin drinlu 



is 



nre- 



tkl effect* on UM system of the habitual gin drinker. 

 Liqueurs are procured by duaolring Tmriotu essential 

 oiU in nlcyhul of various strengths. I'erfumM are manu- 

 factured in a cimilar iii.nm. r ; and occasionally both are 

 Mil.jrcted *o another duiillation, ao a to emu re complete 

 mixture. 



We most now pan on to consider tb effect produced 

 on sugar when the fermentation is pushed on to what 

 hu bean termed the acetous state, or that in which the 

 pint become* converted into an acid. 



If the wort of the brewer, or wash of tho distiller be 

 left, after fermentation, to the free action of the atmos- 

 phere, an acid, called the acetous, U eventually produced. 

 Indeed, this U the method often adopted for the pro- 

 duction of the common vinegar of commerce, and result* 

 from the atmospheric oziilatiun of the alcohol On simi- 

 lar principles, but by different means, alcohol diluted 

 with a littlo water may be converted into acetic iiciil. 

 This u effected by dropping it on some finely divided 

 pUtina,* when the smell of acid produced will be abun- 

 dantly evident. Another arrangement, in which the 

 oxidation and slow combustion of alcohol U produced, 

 is described at the page to which we have just referred. 

 Acetal (C,, H, 4 O.) u a colourless liquid, and may be 

 ]! -luced by the slow oxidation of alcohol through the 

 ac: it>n of finely divided platina. 



Acetic acid combines with several bases forming salts, 

 called acetates. The acetates of lead have already been 

 referred to at a previous page ;t the acetate of iron is 

 employed at a mordaunt in dyeing, and for this purpose 

 is largely manufactured in the North of England. 



Acetate of alumina U similarly employed. 



Of late yean, acetic acid has been extensively used 

 in photography, as a developing agent. That of the 

 strongest kind is generally preferred for the purpose, 

 and U sold under the ii.-une of "Glacial Acetic Acid." 

 It is prepared from the acetate of soda, by distilling that 

 salt with sulphuric acid ; and from the liquid distilled over, 

 crystals may be readily obtained at a temperature less 

 than GO Fahrenheit A considerable quantity of vinegar, 

 containing a portion of acetic acid, with many impuri- 

 ties, has lately been manufactured by the agency of the 

 " vinegar plant" This is a species of fungus, which pro- 

 duces the acetous fermentation in solutions of saccharine 

 matter. The chief source, however, of the vinegar of 

 commerce is ale, which, from having been kept too long, 

 has become "hard" and sour. 



Various combinations analogous to acetic acid are pro- 

 ducible from alcohol, but these are of special intercut to 

 the profeuional chemist only. 



ETHERS. 



An interesting group of substances, which has of late 

 yean received much attention, is found in the ethers 

 which are producible from alcohol by distillation with 

 acids. And we must here call attention to a siiiL'iil.ir 

 phenomenon, in the fact that a substance called Ktlnji 

 (C 4 H ( ), symbol Ae, can assume all the properties of a 

 base, just as a metal might do with oxygen and acid. In 

 fact, thu substance, ethyl, may replace such bases ; form 

 haloid salt*, with chlorine, iodine, Av. ; analogously to 

 sodium or other metal., it may be oxidised ; and thus 

 it opens out a very curious range of organic compounds 

 to our invritiiiRtion. 



Adopting the " Ethyl theory," as it is termed, we shall 

 riew ethyl as the bane of a system of compounds ; and 

 from its various combinations the following substances 

 are obtained, which, with the symbols, we have arranged 

 in a tabular form : 



Base Ethyl c. H. 



le of base-Ether . . C. H. O 

 ate of Oxide . . . C 4 H, O + HO 



Confining our attention, for the present^ to the above 

 oomp..iiiicU, we may sUte that ethyl hat been isolated 

 from iU iodide (C 4 H, 1) by tho action of zinc and heat 

 IWMte, p. ffi. tSMM< l pS. 



E%1 . . C 4 H, + Br 



CI I I Q 



_*_! ' 



. . C 4 H, + Cy 



NO. 



<',H, 

 , H, 



O + C.H^+CjO. 

 0+C 4 H.+C 4 H 4 3 



An inspection of the above table will at once convince 

 the student how completely ethyl replaces a metallic base, 

 in its haloids and salts. And this fact has formed the 

 basis of an entirely now doctrine in chemical science, 

 namely, that of substitution. We shall have again to 

 refer to this point as we proceed. 



With other substances than those we have referred to, 

 ethyl forms interesting compounds. Wine, for instance, 

 owes its bouquet, or rich flavour, to the presence of what is 

 termed "^Enanthic" ether. Butyric, valerianic, magaric, 

 and stearic ether are compounds of ethyl, with the acids 

 bearing their names. 



The other derivatives of alcohol possess, with one ex- 

 ception, less interest than those to which we have directed 

 attention. And we shall, therefore, conclude with some 

 account of chloroform, to which great attention has been 

 directed, owing to its employment in connection with 

 surgical operations. 



Chloral is produced by passing dry chlorine through 

 alcohol, free from water. If, to tho product, soda or 

 potass be added in solution, a decomposition ensues, and 

 chloroform is produced. But the plan usually adopted 

 is, to distil alcohol with chloride of lime. The liquid thus 

 afforded is chloroform ; it has a pleasant smell, and, if in- 

 haled, has the peculiar property of so far influencing the 

 nervous system as to produce almost total insensibility to 

 pain. Its effect* depend, however, very materially, on the 

 temperament of the person inhaling it. In sumo in- 

 stances, we have noticed great cerebral excitement, lead- 

 ing to violent acts. In a cane which came under our 



It U, when condensed, a colourless fluid. Its oxide 

 (C 4 H 4 <>) is the ordinary "xulphurio ether" of the 

 shops, which is obtained by distilling rectified spirits of 

 wine with sulphuric acid. The vapour should b i received 

 in a vessel surrounded with pounded ice. Its sg 

 gravity U less than alcohol, being 0720 (water - 1-000). 

 It is a very volatile fluid ; boils in the air at 96, and 

 under freezing-point in the vacuum of an air-pump ; is 

 highly combustible, and burns with a bright flame. This 

 ether is employed in medicine as a stiniul.mt. If its 

 vapour be breathed, which may be done by pouring a I 

 little of the liquid into a bladder fitted with a mouth- 

 piece, it produces very similar effects to those of the 

 " laughing gas." And it was for some time used, before 

 the discovery of chloroform, in surgical operations, to 

 destroy tho sense of pain. 



On passing tho vapour of ether through a red-hot tube 

 it undergoes decomposition, and "aldehyde" U produced. 

 This substance is a hydrated oxide of "acetyl" (C 4 H 8 ), 

 and hence its composition is C 4 H 3 O + HO. A connec- 

 tion with the ethyl series, and that to which acetic acid 

 belongs, is thus established. And the products of the 

 decomposition of alcohol and ether are respectively ho- 

 mologated. 



liy using hydrochloric instead of sulphuric acid, in dis- 

 tillation with spirits of wine, as just described, the chloride 

 of ethyl is produced (C 4 H, Cl), commonly known as 

 chloric ether. Nitric ether (C 4 H N0 5 ) is similarly 

 produced, by the action of nitric acid on rectified spirits 

 of wine. 



We have confined our attention, chiefly, to those forms 

 of the combinations of ethyl which are more generally 

 known. A large number of others, however, has been 

 discovered ; and as they have no special interest we shall 

 only give the symbols showing their constitution. 



Ethyl Compounds, in addition to those already named. 



Bromide of 

 Sulphide 

 Cyanide 

 Sulphate of Oxide of 

 Nitrate ,, 

 Carbonate of 

 Oxalate 

 Acetate 



