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In his sixth and last book, Mr Huinboldt treats of the reveDue and military defence of New Spain. On these subjects we must be extremely concise.

The following tables, selected from a vast number of others, will show the progress of the revenues of New Spain, their present amount, and their general application.

Dollars. (1.)

r1712.......... 3,068,400

1763........... 5,705,876 Gross revenue of New Spain in 1780....... 15,010,974

1783...

19,605,574 1802...

20,200,000 (2.) Gross revenue, according to the estimate of Mr Humboldt in 1804......

20,000,000 Expense of interual government...... 10,500,000 Remittances to the other colonies, in

order to defray the expenses of their internal government......... 3,500,000 Clear revenue remitted to Madrid... 6,000,000

20,000,000 The colonies, to which regular remittances are sent from New Spain, are Cuba, Porto Rico, Florida and Manilla. The government of Cuba has, besides, two millions of dollars from the revenue of the island; and that of Manilla 1,700,000. The subjects of Spain in the Philippine islands are reckoned at 1,900,000.

The appointments of the Viceroy of New Spain are inconsiderable, being only 60,000 dollars, or little more than 13,0001.

But his indirect means of amassing wealth are immense. There are viceroys, who, after a few years residence in Mexico, have retired with a fortune, which they had acquired there, of eight millions of livres, or above 320,0001. When we consider the fraud, injustice and extortion, with which such fortunes must have been accumulated, we cease to wonder at the detestation in which the name of Viceroy is held throughout America.

The following is Mr Humboldt's estimate of the clear revenue which the court of Madrid derives from its American possessions,

Dollars.
From New Spain........

6,000,000 Peru........

1,000,000 Buenos Ayres.......

700,000 New Grenada......

500,000

8,200,000

'The receipts of Goatemala, Caracas, and Chili, are consumed within the country. Cuba, Porto Rico, and Manilla, require annual remittances from Mexico. The population of the Canary islands is reckoned at 180,000 persons, and their revenue at 240,000 dollars; but the expense of their government is such, that they require an aunyal remittance from Spain.

The military establishment of New Spain was composed, in 150+, of 10,000 troops of the line, and 22,000 militia,--about one half of both consisting of cavalry. The light cavalry are represented as good,

ART. VI!I. Experiments to ascertain ihe Slate in zhich Spirit

erists in Fermented Liquors; with a Table, exhibiting the relative Proportion of pure Alcohol contained in several kinds of Wine, and some other Liquors. By William Thomas Brande,

Esq. F. R. Ş. (From Phil. Trans. for 1811, Part II.) An Account of a Vegetable War from Brazil. By the same.

(From the same Work.)

We have more than once had occasion to notice the experi

ments of this gentleman, by whose assistance Mr Home and other inquirers have often greatly benefited, in conducting their experimental investigations. The two papers which he has contributed to the present volume of the Transactions, are not of any very superior importance; but they deserve some attention,--the one; as throwing doubts upon a subject of considerable interest, and thus leading to further discussions—the other, as describing a new, or hitherto unnoticed substance.

The reccived opinion, that alcohol, though obtained by distilling wines, does not exist already formed in the wine, but is a product of the distillation, arising from a new combination of the carbon and hydrogen existing in the vinous tiuid, engaged our author's attention in the first of these

papers. He conceives that he has overthrown this doctrine, and established the opposite one; and as we think him a good deal more confident than his experiments warrant-or at least that, if he has overthrown the proofs of the old doctrine, he has failed in offering sufficient evidence of his own—we must attend somewhat minutely to his deductions.

The experiments of Fabroni, upon which chiefly the receira ed opinion rested, consisted of processes by which alcohol was detected when mixed with wine, but which failed to separate any alcohol from the wine itself. In the outset, we may remark,

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that unless his experiments were confined to a very small number of wines, they are inconsistent with themselves; for, as most wines have a mixture of spirits added in the making, and as Fabroni said he could detect alcohol in so small a proportion as one hundredth when it had been added, there are very few wines indeed, in which, by his own principle, it should not have been discoverable. But Mr Brande gives a more general and satisfactory refutation, by repeating his processes. They consisted in adding dry subcarbonate of potash to the vinous fluids, so as to saturate them. Our author distilled a pint of port wine, and obtained eight ounces of spirituous fluid in the receiver. This, being mixed with the subcarbonate, gave about three fluid ounces of spirit. The same process being repeated, except the mixture of subcarbonate, the liquor in the receiver was mixed with that in the retort, and no addition of subcarbonate was found to effect any separation of alcohol. Now, by Fabroni's test, as applied to the liquor in the receiver, there was alcohol here, and thirty times more in quantity than was necessary to be detected,-and yet it escaped ; so that it may safely be inferred, that he had been misled by some false appearances. Mr Brande made many other trials, with similar results. When wine was saturated with subcarbonate, a separation took place in the vessel,—the lower part being filled with a strong solution of subcarbonate, and the upper part with a gelatinous substance, ' which appeared to contain the alcohol of the wine, with the principal part of the extract tan and colouring matter, some of the subcarbonate, and a portion of water.' The same experiment being repeated with wine, to which one seventh part of its weight of alcohol was added, no separation of spirit took place, beyond that in the former trial. One third of alcohol being added to wine, and the experiment repeated, a stratum of impure spirit was separated, and floated on the top ; but, when three fifths were added, a quantity of spirit readily separated on the admixture of subcarbonate, and floated on the top; while the gelatinous matter went below, and the bottom of the vessel contained solution of subcarbonate. From wine, however, in its ordinary state, or even with a considerable admixture of alcohol, this process, and all the others which our author could devise, wholly failed of separating the spirituous part. He used carbonate of lime in order to take away the acid; bụt still the alcohol adhered strongly to the residuum.. He tried limewater, which is commonly said to separate the colouring, maiter, as well as the acid ; but he could not effect such a separation. Distillation, therefore, was the only method ; and, unfortunately, the use of it cannot decide the question : for the

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very

very point in dispute is, whether this process does not form, as well as show, the spirituous fluid.

In order to decide this--and it is the only direct argument which he advances--our author observes, that if the alcohol be produced by the process, and not merely drawn out by it; or, to use his own expression, if alcohol be a product, and not an educt, we may expect different proportions of it to be obtained by distilling, in different temperatures. Accordingly, he raised the boiling point of eight ounces of wine to 200° of Fahrenheit from 190°, by mixing it with muriate of lime, and distilled off four ounces of fluid. The specific gravity of this fluid was 0.96316. The experiment being repeated without any admixture of muriate, and consequently at a temperature of ten degrees lower, the same quantity of liquor in the receiver was taken, and found to have nearly the same strength, its specific gravity being 0.96311. The process being repeated in a water bath, the specific gravity of the liquor in the receiver was 0.96320 ; and the distillation being carried on at a temperature of only 180°, it was necessary to continue it for four or five hours daily during five days, in order to obtain the same quantity of liquor in the receiver ; but its specific gravity was 0.96314. The quality of the liquor, then, does not seem to be at all affected by the heat applied in obtaining it. Thus far we admit his inference to be correct. But the argument founded upon it is by no means decisive of the question : For, to pass over other considerations, these experiments, strictly speaking, only show that a difference of twenty degrees makes no difference in the process, whatever it may be, by which alcohol is obtained from wine in distillation. Thus, if we adopt the common opinion, which Mr Brande is combating, these experiments only prove, that a heat of 180° of Fahrenheit is suflicient, though much more slowly, to effect the union of hydrogen and carbon, from which alcohol results in the decomposition of wine. A probability may arise from this circumstance, and, added to others, it night help to determine our opinion. But it is not in science, as in matters of a practical nature, where some decision must be formed; and, in default of the best evidence, we must have recourse to proofs of an inferior description, and sometimes must even act on conjecture and presumptions. In science, nothing is decided but on the highest species of proof which the kinds of inquiry severally allow; and, where those are wanting, it is fit, not that we should be satisfied with worse evidence, but that we should rest satisfied with our present state of knowledge, and abstain from drawing any new conclusions, until the proper means of demonstration shall be afforded uö. If this golden rule had always been attended to, what worlds of unprofitable controversy and useless theories, or rather vague hypotheses, prejudicial to the progress of knowledge, and fruitful in errors, would have been avoided !

Mr Brande endeavoured to separate the alcohol from the wine by freezing; but this only forms the wine into a spungy mass, without separating any spirit

. He also froze a mixture of alcohol and water with the residuum of wine which had been evaporated; but it formed a cake as before.

Where the temperature is slowly reduced, and a large quantity of wine operated on, a portion of the watery part freezes before the rest, and thus leaves that residue considerably stronger. But nothing like a separation of alcohol can be obtained in this manner; and it is evident that the freezing of the water leaves the question, of the existence of alcohol in the vinous residue, precisely where it found it.

Such being the whole amount of our author's experiments and reasonings in the first section, it is somewhat unexpectedly that we find him becin his second section with these words Hav. ing ascertained that alcohol exists in wine ready formed, and " that it is not produced during distillation, I employed that • process to discover the relative proportion of alcohol combin' ed in different wines.' Now, it is quite manifist, that, so far from having ascertained any such thing--- which would in truth have been deciding the whole question-Mr Brande has ascertained something, not unimportant indeed, but perfectly dillerent, and which leaves the question unresolved. He has only ascertained, that part of Fabroni's experiments are erroneous, and that his inference, of consequence, is fallacious ;-in other words, that the comien opinion is not yet demonstrated, and the question still unsettled, which had been conceived to be determined the other way. So that, instead of saying, there is proof of alcohol being a product of distillation, we must now say, there is no such proof; while, on the other hand, Mr Brande bas not shown that it is an educt. It may still be either the one or the other, for any thing we know. lieally this hastiness in jumping at a conclusion, by the common process of begging the question, is somewhat unpleasant. It looks as if the inquiry in This paper had been undertaken, not so nuch with a view to inrestigate a speculative point, as for the sake of giving a comparative table of the strengih of wines, in the way of making kliich, there stood a difficulty which must be quickly disposed of.-We now come to the Table, which is certainly curious, though its value is considerably in paired by the equivocal na[ure of the grounds it rests on.

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