312 ANNUAL OF SCIENTIFIC DISCOVERT. 



which I am at present investigating. Analyzed by oxygen in the endiome- 

 tcr, it gives equal volumes of carbonic acid and sulphurous acid, from 

 which we may deduce the formula CS as representing its composition. 



Many chemists have attempted to discover this body ; and its having es- 

 caped their investigation, is attributable, without doubt, to its reaction upon 

 water and the solutions of the alkalies, which resolve it into carbonic oxide 

 and sulphuretted hydrogen. Comptes Rendus. 



ON THE CHEMISTRY OF WINES. 



Mulder, the celebrated German chemist, has published during the past 

 year an interesting contribution to popular science, entitled the " Chemistry 

 of Wine." Referring to the little progress which has yet been made in the 

 accurate analysis of the various kinds of wine, he says : The almost un- 

 limited variety which is peculiar to wine, and depends entirely upon varia- 

 tions in the constituents of the wine, has never been traced back to its cause ; 

 and further, many methods of determining even the most ordinary vinous 

 ingredients are still imperfect, and must be replaced by others. Lastly, there 

 are many adulterations practised upon wine, which keep pace with the ex- 

 tension of chemical knowledge, and which have been as yet by no means 

 sufficiently explained. We have only to consider the immense multitude of 

 wines, all differing in color, odor, flavor, to be satisfied that an exact chemi- 

 cal knowledge of them must be almost impossible. The composition differs 

 according as the wine is red, or not red. In the last mentioned, no particu- 

 lar coloring matters arc found, and only a trace of tannic acid ; in the for- 

 mer both are present. Alcohol and water are also among the principal in- 

 gredients, then sugar, gum, extractive and albuminous matters ; then free 

 acids, such as tartaric, raccmic, malic, and acetic acid, tartrate of potash, of 

 lime, and of magnesia, sulphate of potash, common salt, and traces of phos- 

 phate of lime ; also, and especially in cellared wines, substances which im- 

 part aroma, as cenanthic and acetic ether, in variable proportions, and other 

 volatile matters. In red wines and in many others, a little iron, and, 

 according to one statement, some alumina, may also be detected. Lastly, 

 the best wines contain, according to Faure, a peculiar substance, which lie 

 calls oenanthinc. These ingredients vary exceedingly in proportion. The 

 quantity of some is so insignificant, that the substance almost disappears 

 during analysis. The quantity of some may be determined by weight, and 

 of others again is still greater. Most of the properties of wine depend upon 

 the sugar, alcohol, tartaric acid, and water, which exist together in it; that 

 is, putting aside taste and smell as standards of comparison. By a com- 

 paratively rough analysis the proportions of the chief ingredients may be 

 ascertained, but no chemistry can detect the formation or exhibit the exist- 

 ence of the aroma which gives to some wines their fabulous value. Science 

 can investigate the organic constituents and point out the relation between 

 the ingredients of the soil and the vegetable structure, but science is unable 

 to bring the structure of plants into connection with the nature of their special 

 products. 



