The revenue in jeopardy from spurious chemistry, demonstrated in researches upon wood-spirit and vinous-spirit / [Andrew Ure].

  • Andrew Ure
Date:
1843
Catalogue details

Licence: Public Domain Mark

Credit: The revenue in jeopardy from spurious chemistry, demonstrated in researches upon wood-spirit and vinous-spirit / [Andrew Ure]. Source: Wellcome Collection.

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    mixed by Mr. John Barling’, of New York, with his Yankee spirits of wine, to compound such a fictitious naphtha, as might do the British Exchequer out of a little of its spare cash, and the British Chemists out of a little of their spare fame. Since cream always contains more or less milk, though milk often contains no cream, as a Londoner knows full well; such are the relations of rough naphtha and pyroligneous acid. Mr. Ross requested me to reconsider the subject, and to an¬ swer these certificates. Having fortunately reserved the greater portion of the original sample bottle, immediately on my return home, 1 instituted a se¬ ries of careful experiments upon it; and on the 7th of January, handed the following report into the Surveyor-general’s office : “ In compliance with the request you made me yesterday at our consultation in your office upon the naphtha imported at Liverpool, which t examined on the 22d of November last, by desire of the Hon. Commissioners of Customs, I have now the, pleasure to submit to you the following justification of the cer¬ tificate I then granted, which will serve to refute the counter- certificates since furnished, as you write me, by a Professor and a practical Chemist:— “ When two liquids are equally volatile, as is the case with al¬ cohol and naphtha, or wood-spirit, it is utterly impossible to sepa¬ rate them completely by distillation, or by any direct methods, and this fact is no doubt well known to the compounder of this spurious naphtha. Surely no man, even moderately versant in Chemistry, would presume to deny the existence of alcohol in the said naphtha, because, forsooth, the two fluids are inseparable by dis¬ tillation. In like manner, when lead and tin are combined, as in solder, it is impossible to separate them by fusion, because they melt together; but they may however be most easily parted by the action of nitric acid, which converts the tin into an insolu¬ ble oxide, and the lead into a soluble salt, and then the two metals may be perfectly separated by mere washing with water, and the quantity of each exactly ascertained, from the known composition of tin oxide and nitrate of lead. “Thus, also, when alcohol and naphtha are mixed, we must have recourse to an indirect but a quite accurate method of parting them, and estimating the proportion of each in the mixture. In the present case, however, that is hardly necessary, since, on rectifying the spurious naphtha by distillation with quicklime, I could distinguish plainly, by the taste and smell, the presence of alcohol in very large proportion in the purified spirit. “ 1. When alcohol of from fifty to sixty per cent, over-proof is mixed with its own weight of sulphuric acid, and properly dis-
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