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This, of course, gives the advantage of cheapness in the first cost, in their favour, as well as that of saving freight.

The quantity of fuel consumed is a most important item in navigating by steam, both on account of the cost, and also of the freight in long passages. Those who navigate by high steam assert that "their daily consumption in passages of five or six hours, is about two and a half cords, whereas the low pressure boats use four or five cords under similar circumstances." This, however, is not entirely admitted by their opponents. There are two circumstances that indicate the advantage on this point to be in fa vour of high steam. In the first place, if one engine with its appendages be twenty tons heavier than the other, it must afford a much greater surface by which its heat may be dissipated, for the whole apparatus must be pervaded by the heat. In the second place, the elasticity of steam increases in a ratio nearly geometrical, while the temperature is increasing in arithmetical progres sion. Thus we see that it requires but little additional heat to give a very superior degree of elasticity. This, by the by, is also the reason why a weak boiler may be exploded by a small increase of heat.

"The average work performed by thirty-three engines of Boulton and Watt, in Cornwall, in May, 1817, was, according to Messrs. Lean's report for that month, 20,897,040 pounds of water, lifted one foot high with each bushel of coal consumed. During the same month, the work done by Woolf's engine (high pressure) at Wheal Vor, was 49,555,244, and by his engine at Wheal Abraham 56,917,312 pounds, lifted one foot high by each bushel of coal. By Messrs. Lean's report for June, the average work of twenty-eight engines was 20,884,326 pounds, lifted one foot high with each bushel of coal; and during the same month, Woolf's engine at Wheal Vor, 43,161,819, and at Wheal Abraham, 51,476,482 pounds of water, lifted one foot high with each bushel of coal consumed."

[Augustan Review, September, 1816.

The city of Philadelphia has been hitherto supplied with water, by means of a low pressure engine. A high steam engine made by Oliver Evans is now substituted in its place, and has been in operation a few weeks. It is stated by those who conducted the operation, during the proof experiments to which it was subject

ed, that the supply of water can now be rendered with much greater certainty and expedition, and with a saving, in fuel alone, of seventeen dollars per day.

The experiments with the mineral water coppers, which we have stated above, will show how very thin the low pressure boilers may be made, and yet be perfectly safe, as long as the pressure is at or below four pounds on an inch. Mr. Evans's boilers have been shown to be perfectly safe at 150. There is then nothing necessary to insure the safety of the passengers in boats worked by either, but to guard against the increase of steam beyond its prescribed limits. Heretofore this has been attempted by loading the safety valves to a limited point, and by a mercurial guage kept for the use of the workmen. Experience has shown that neither of these can be relied on, for dreadful accidents have occurred when both were in operation. They are in the hands of the workmen, and can be altered so as to deceive all other persons on board, whenever it is desirable to increase the speed against a rival, and whenever, through accident or carelessness, the safety valve is left too heavily loaded. Another expedient has been proposed, which, in conjunction with the safety valve, it is believed would always insure the safety of the passengers. This consists in placing a sthenometer in the cabin, which will constantly indicate, to every person on board, precisely the pressure which is then operating. This instrument is formed like a thermometer, and was invented by Dr. James S. Ewing, of this city. The rise of the mercury indicates the pressure of the steam. The graduations show the number of pounds per inch; so that when the mercury rises to 4, it indicates that the pressure in the boiler is equal to four pounds on the square inch, or that which should not be exceeded by low pressure engines; and when it rises to 150, it shows the pressure to be such as should not be exceeded by high pressure engines. It is so simple, that every person on board will readily understand it. When such an instrument can be had at a trifling expense, the owners of boats seem to be under an obligation to furnish their passengers with the means of knowing when their lives are put at hazard by the carelessness or mismanagement of those who conduct the boat. In a case in which such dreadful accidents have taken place, and the ordinary me

thods of preventing them have failed, common prudence would require that every mode of guarding against danger should be adopted. The sthenometer cannot be altered by the boatmen so as to give a false indication, as both the steam guage and safety valve can be. If they do not injure it so as to prevent its acting at all, it must give the pressure truly. It has been applied to a steam engine of high pressure so as to prove its accuracy, and it has been used for several years, by many persons, in making mineral waters, where the pressure is greater than in high steam engines; and although it has not been assisted either by the steam guage or safety valve, so sensible is it to the least variation of pressure, and so true its indications, that no accident has ever happened where it was used, while dangerous and even mortal explosions have taken place every season among those who have operated without it.

From all that has been said, we may reasonably conclude, that if the plan of having two safety valves, and subjecting the boilers to occasional trials of their strength, as proposed by the Councils of Philadelphia be adopted, and a sthenometer for the use of the passengers be placed in the cabin, steam boat navigation will be rendered as safe as it is pleasant.

THE SPANISH COLONIES.-FOR THE PORT FOLIO.

It was our intention to have given a connected view of the transactions in relation to this highly interesting subject, in this Number of our work; but the want of room compels us to defer it until the next month. As it will probably be brought before the Congress immediately, we deem it proper to publish, without delay, the opinion of one of our most sagacious statesmen, on a matter of so much moment. It will be found in a letter from Gen. Hamilton, in reply to one from Miranda, in which the following passages are to be found: "it appears," says that unfortunate patriot, "that the moment of our emancipation approaches, and that the establishment of liberty throughout the new world is intrusted to us by Providence. The only danger, in any apprehension, will be from the introduction of French principles, which would poison our liberty at its birth, and end by overturning yours."

The plan of operations upon which these sanguine expectations were founded, was intrusted to a person who was about to proceed to this country from England; but who, it appears, had not arrived when Hamil ton wrote his answer.

SIR,

New-York, 22d August, 1798.

I HAVE lately received, by duplicates, your letter of the 6th of April, with a postscript of the 9th of June. The gentleman you mention in it has not made his appearance to me, nor do I know of his arrival in this country; so that I can only divine the object from the hints in your letter. The sentiments I entertain with regard to that object have been long since in your knowledge; but I could, personally, have no participation in it, unless patro nized by the government of this country. It was my wish that matters had been ripened for a co-operation in the course of this fall, on the part of this country, but this can now scarce be the The winter, however, may mature the project, and an effectual co-operation by the United States may take place. In this case I shall be happy, in my official station, to be the instru ment of so good a work.

case.

The plan, in my opinion, ought to be a fleet of Great Britain, an army of the United States-a government for the liberated territories, agreeable to both the co-operators, about which there will be, probably, no difficulty. To arrange the plan, a competent authority from Great Britain to some person here, is the best expedient. Your presence, here, in this case, will be extremely essential.

General

We are raising an army of about 12,000 men. Washington has resumed his station at the head of our armies; I am appointed second in command.

With esteem and regard,

I remain, dear sir,

Your very obedient servant,

GEN. MIRANDA.

A. HAMILTON.

THE AMERICAN LOUNGER.-FOR THE PORT FOLIO.

MR. SAUNTER,

MISS EDGEWORTH AND THE JEWS.

The story of HARRINGTON by Miss Edgeworth, has excited more than common attention, because it is stated to have been written to conciliate a particular description of people-one of whose members, "an American lady," had complained that her society had been harshly treated in the writings of that celebrated author. Harrington, the hero of this tale, is captivated by a young lady of the Hebrew stock. Both himself and his parents, entertain violent prejudices against Jews. These prejudices in due time, are removed by concurring circumstances; yet, her religion being an insurmountable bar to their marriage, it is suddenly discovered that she had been educated a christian!-and all concludes happily in the usual way.

One of our critics in the NEW-YORK MAGAZINE, after commenting with sufficient amplitude on novel-writing in general, and Miss Edgeworth's manner in particular-gives a summary of this fashionable tale, and concludes with the following remarks: "Miss Mentonero is a lovely, sensitive, interesting girl-but she " is no Jewess! and the whole fabric, which the author had raised, "falls before this single fact. By doing away this prominent im"pediment to the union of the lovers, she completely destroys the "interest of the reader, and the moral of her tale. The mode "adopted to dispose of the difficulty, is a tacit admission that it "could be got over in no other way. Miss Edgeworth is quite "willing to allow the Jews to be very clever, good people-but "it is pretty plain that she does not think a Hebrew damsel a "proper helpmate for a John Bull.”

We readily agree with this writer, that by removing the impediment to the match, she has destroyed the interest of the readerbut not, we hope, the fabric she meant to raise, or the "moral of her tale." Her design was simply to concede that Jews are like other men-good and bad-and this she has effected. But had she intended to inculcate that heartless liberality which supposes that conflicting opinions in the most essential articles of a religious creed, should be no impediment to a matrimonial union

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