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Finding that the separation of alcohol by subcarbonate of potash from mixtures of spirit and water, was nearly complete, and that colouring-extractive matter, and tartaric acid might be removed from such mixtures by the subacetate of lead, I proceeded to examine wine by such modes of analysis.
The following results were obtained by these, and other comparative experiments.
1. One part by measure of a concentrated solution of subacetate of lead, was added to eight measures of common port wine: the mixture having been agitated for a few minutes, was poured upon a filter.—The filtrated liquor was perfectly colourless, and the addition of dry subcarbonate of potash effected a rapid separation of alcohol.*
100 measures of the wine thus treated, afforded 22,5 measures of alcohol.
2. Eight ounces of the wine employed in the last experiment, were distilled in glass vessels, as described in my former paper. The specific gravity of the distilled liquor at the temperature of 60° was 0,97530, which indicates 22,30 per cent. by measure of alcohol of the specific gravity of ,8250.
3. Eight ounces of the same wine were introduced into a retort placed in a sand heat, and the process of distillation was stopped when six ounces had passed over into the receiver.
of the subcarbonate, was always within 0,5 per cent. of the real proportion contained in the mixture. So that in the examination of wines containing less than 12 per cent. of alcohol, the method described in the text is somewhat exceptionable. The above experiments were made in glass tubes varying in diameter from 0,5 inch to 2 inches, and accurately graduated into 100 parts.
• When any excess of the subacetate had been employed, a portion of carbonate of lead was thrown down; but this did not interfere with the subsequent separation of the alcohol.
After the vessels were completely cooled, the portion in the receiver was added to the residuum in the retort. The specific gravity of this mixture ( ascertained with proper precautions) was ,9884, that of the original wine = 0,9883. *
When care was taken to prevent the escape of vapour, no change of specific gravity was produced in the wine by three repetitions of the above process.
Similar experiments were repeated upon Madeira, Sherry, Claret, and Vin de grave, wines differing in the relative proportions of alcohol, colouring matter, and acid which they contain, and the results were as decisive; so that I conceive it is amply proved, by experimental evidence, that no alcohol is formed during the distillation of wines, and that the whole quantity found, after distillation, pre-existed in the fermented liquor.
It has been frequently asserted, that a mixture of alcohol and water, in the proportions I have stated them to exist in wine, would be much more effectual in producing intoxication, and the general bad effects of spirituous liquors, than a similar quantity of the wine itself. But this is true to a very limited extent only: when brandy is added to water, it is some time before the two liquids perfectly combine, and with alcohol this is more remarkably the case, and these mixtures are warmer to the taste, and more heating, if taken in this state of imperfect union, than when sufficient time has been allowed for their perfect mutual penetration.
I have also ascertained that distilled port wine tastes stronger, and is more heating than the wine in its original state, and that these qualities are impaired, and the wine reduced nearly * This experiment was suggested in the Edinburgh Review for November, 1811.
to its original flavour, by the addition of its acid and extrac-
former the average quantity of alcohol contained in port wine amounts to 23,48 per cent.; but two of the wines there alluded to are stronger than any I have since met with, and were, at that time, sent to me as “ remarkably strong and old port." I have lately examined a number of specimens of the better kinds of port wine in common use, and the results of these experiments lead me to place the average strength at 22 per cent. of alcohol by measure.
A port wine procured for me by Dr. BAILLIE, and to which no brandy had been added, afforded 21,40 per cent. of alcohol: another specimen of a similar description, put into my hands by an Oporto merchant, contained only 19 per cent.; it is the weakest port wine I have met with.
The other results given in the table, agree perfectly with those of subsequent and more extended experiments.
XI. On a new Variety in the Breeds of Sheep. By Colonel David
Humphreys, F. R. S. In a Letter to the Right Hon. Sir Joseph Banks, Bart. K. B. P. R. S.
Read January 14, 1819.
In the year
Humphreysville (in the State of Connecticut), Nov. 1, 1811. I
PROPOSE to give some account of a new variety in the breeds of sheep, which has lately sprung up in America.
Seth Wight, who possessed a small farm on the banks of Charles river, in the town of Dover and State of Massachusetts, about sixteen miles distant from Boston, kept a little flock composed of fifteen ewes and one ram. 1791, one of the ewes produced a lamb of singular appearance. By the advice of some of his neighbours, he killed his former ram, and reserved the young one for breeding. The first season, two lambs only were yeaned in his likeness. In the following years, a number more, distinguished by the same peculiarities. Hence proceeded a strongly marked variety in this species of animals, before unknown in the world. It has been called by the name of the Otter breed.
This name was given from a real or imaginary resemblance to that animal, in the shortness of the legs and length of the back; by some supposed to have been caused by an unnatural intercourse; by others, perhaps as fancifully, from fright during gestation. It is only certain, that otters were then
sometimes seen on the banks of this river. They have since disappeared.
The person, who was the first to dissect one of these sheep for the purpose of ascertaining the properties and qualities which distinguish them from our common breed, has added the appropriate term of AncoN.
The singularity of form seems to be confirmed in the blood. Experiments, in crossing, have changed the strain, or, if I may be allowed so to express it, amalgamated the qualities of this with those of other breeds, so as to produce a mixed or mongrel race, in too few instances to form an exception to the theory.
When both parents are of the otter or ancon breed, the descendants inherit their peculiar appearance and proportions of form. I have heard of but one questionable case of a contrary nature.
The small number of cases where the young are said to partake in part, but not altogether, the characteristics of this breed, will not invalidate the general conclusions, established on experience in breeding from a male and female of distinct kinds.
When an ancon ewe is impregnated by a common ram, the increase resembles wholly either the ewe or the ram.
The increase of a common ewe, impregnated by an ancon ram, follows entirely the one or the other, without blending any of the distinguishing and essential peculiarities of both.
The most obvious difference between the young of this and other breeds, consists in the shortness of the legs of the former; which combined with debility or defect of organization, often makes them cripples in maturer age.