676 THE POPULAR SCIENCE MONTHLY. 



nal of Science " of April, 1877. The editor adds that the inventors of 

 this jjaj^er have discovered a method of removing the magenta from 

 wines without injuring their quality, " a fact of some importance, if 

 it be true that several hundred thousand hectolitres of wine sophisti- 

 cated with magenta are in the hands of the wine-merchants " (a hecto- 

 litre is equal to twenty -two gallons). 



Another simple test, that was recommended at the time, was to 

 immerse a small wisp of raw silk in the suspected wine, keeping it 

 there at a boiling heat for a few minutes. Aniline colors dye the silk 

 permanently ; the natural color of the grape is easily washed out. I 

 find, on referring to the " Chemical News," the " Journal of the Chem- 

 ical Society," the " Comptes Rendus," and other scientific periodicals 

 of the period of the phylloxera-plague, such a multitude of methods 

 for testing false-coloring materials that I give up in despair my origi- 

 nal intention of describing them in this paper. It would demand far 

 more space than the subject deserves. I will, however, just name a 

 few of the more harmless coloring adulterants that are stated to have 

 been used, and for which special tests have been devised by French 

 and German chemists. 



Beet-root, peach-wood, elderberries, mulberries, logwood, privet-, 

 berries, litmus, ammoniacal cochineal, Fernambucca-wood, phytolacca, 

 burned sugar, extract of rhatany, bilberries ; " jerupiga " or "geropiga," 

 a " compound of elder-juice, brown sugar, grape-juice, and crude Port- 

 uguese brandy" (for choice tawny port); "tincture of saffron, tur- 

 meric, or safiiower" (for golden sherry); red poppies, mallow flow- 

 ers, etc. 



Those of my readers who have done anything in practical chemis- 

 try are well acquainted with blue and red litmus, and the general fact 

 that such vegetable colors change from blue to red when exposed to an 

 acid, and return to blue when the acid is overcome by an alkali. The 

 coloring-matter of the grape is one of these. Mulder and Maumene 

 have given it the name of cenocyan or wine-hlue, as its color, when 

 neutral, is blue ; the red color of genuine wines is due to the presence 

 of tartaric and acetic acid acting upon the wine-blue. There are a few 

 purple wines, their color being due to unusual absence of acid. The 

 original vintage, which gave celebrity to port wine, is an example of 

 this. 



The bouquet of wine is usually described as due to the presence of 

 ether, cenanthic ether, which is naturally formed during the fermenta- 

 tion of grape-juice, and is itself a variable mixture of other ethers, 

 such as caprilic, caproic, etc. The oil of the seed of the grape con- 

 tributes to the bouquet. The fancy values of fancy wines are largely 

 due, or, more properly speaking, were largely due, to peculiarities of 

 bouquet. These peculiar wines became costly because their supply 

 was limited, only a certain vineyard, in some cases of very small area, 

 producing the whole crop of the fancy article. The high price once 



