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tion to the velocity with which the water moves; but when; water is made to descend on an inclined plain, towards a mill wheel, its velocity encreases every

inch it moves forward, so as to be much greater at the bottom of the spout, where it reaches the wheel, than at the top of it; and consequently the depth of the fheet of water is much less where it reaches the wheel than it was at the top of the spout.

This being understood, let us now suppose, that in a trough of one foot diameter, and where the A A's are, by consequence, of the same length, such a stream can be commanded as to fill the trough at the top of the spout, so as to be on an average six inches deep ; on a very moderate fall, that sheet of water where it reaches the wheel would not be four inches, [if tolerably great it would not be two inches.] Now if we suppose the interval between the A A's and the trough to be no more than half an inch, it would follow, that one eighth part of the dead weight of the water would be lost. If it were one inch, which is no uncommon case, the loss would amount to one fourth part of it.

If, with a view to improve this machinery, the trough should be widened, and the A A's lengthened to two feet, the consequences would plainly be these : the depth of the water at the top of the spout would now only be three inches instead of six, and of course the thickness of the sheet, where it reaches he wheel, would be only two inches, instead of four ; but as there must still be half an inch of water lost, as before, it follows that one fourth part of the dead weight of the water must now be lost instead of one eighth. Here then the loss is precisely double what it was before, without any advantage gained to counter-baLance that ;-augment that breadth to four feet, you once more double that absolute lofs, (the proportional lofs is much greater,) and so on, the more you encrease the breadth of your wheel, in these circumstances, the greater must the loss of power be ; so that, instead of an improvement, this innovation is in fact a very considerable deterioration. Indeed it would be easy to show that in many cases the whole of the power of the water, as a dead weight, is thus entirely lost, so that it can act merely by its impetus.

Observe, what is here said respects wheels constructed with A A's ; those with buckets, or receivers of any sort, will be considered below. But in most of these, as far at least as respects that part of the wheel below the axis, the case will not be found to differ much from what is here stated.

These observations may be sufficient to show that in all cases where a considerable fall of water can be commanded, there must ever be a great waste of that "water as a moving power, when it is applied to wheels constructed with float boards or A A's, and to point out in what manner that waste

may be augmented or diminished. In that mode of construction it is chiefly by its impetus that water acts upon machinery. It remains that we now consider the various modes of applying water to machinery so as to make it act by its dead weight; a mode of application that ought in every case to be adopted where the fall is considerable. As this branch of the subject has ne

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ver attracted the attention of mechanics so much as it deserves, and seems to be but little understood by the public at large, it will be of use to advert to it with care, which shall be done in a subsequent paper.

To be continued.

For the Bee.
COPY OF A SINGULAR LETTER FROM LIEUTENANT CO-

LONEL CHARLES SKENE, GOVERNOR OF EDINBURGH
CASTLE, TO THE EARL OF TWEEDDALE.
My LORD,

Edinburgh castle, Oct. 29. 1667. I RECEIVED a letter this morning from my tutor John Kirkwood, wherein he tells me, your lordship was pleased to command him to let me know that

you

had seen a letter directed to the archbishop of Canterbury, which gives him an account of a rebellion that is to be in Scotland, and that the commander of the Castle of Edinburgh was to declare himself for the rebels.--I shall not say much, but by G-d's wounds I shall be as honest and faithful in my trust as that bishop, or any other gownsman; and let him and them go to the the devil and bishop them : nor shall I ever counterfeit any letter that may be to my neighbour's hurt to keep myself great; for I am afraid it is their guilty consciences invents these and the like stories; and I hope whatever inay be writ to them of me, the king my master will have charity for me ; for God damn me that day I ever betray my trust to them or any else. O! my lord, forgive me; for I am almost mad; and in such a confusion that I know not what I am writing ; but I am, and shall be, in spite of Toland, my lord, your lordship’s most obedient seryant, (Signed)

CHARLES SKENE.

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REVIEW. THE POLITICAL PROGRESS OF BRITAIN; OR AN IMPARTIAL AC

COUNT OF THE PRINCIPAL ABUSES IN THE GOVERNMENT OF THIS COUNTRY, FROM THE REVOLUTION IN 1688. THE WHOLE TENDING TO PROVE THE RUINOUS CONSEQUENCES OF

POPULAR SYSTEM OF WAR AND CONQUEST, PART FIRST. Edinburgh, Robertson

Berry, 1792.

Is.

as already appeared in the Bee, under the form of letters from Timothy Thunderproof, so that our readers are already in some measure able to judge of it. The author, in a short intro. duction, thus justly characterises the performance him. self.

“ This pamphlet consists not of fluent declamation, but of curious, authenticated, and important facts, with a few fhort observations interspersed, which seemed necessary to explain them. The reader will meet with no mournful periods to the memory of annual or triennial parliaments; for while the members are men, such as their predecessors. have almost always been, it is but of small concern whether they hold their places for life, or but for a single day. Some of our projectors are of opinion, that to shorten the duration of parliament would be an ample remedy for all our grievances. The advantages of a popular election have likewise been much extolled. Yet an acquaintance with Thucydides, or Plutarch, or Guicciardini, or Machiavel, may tend to calm the raptures of a republican apostle. The plan of universal suffrages has been loudly' recommended by the duke of Richmord; and, on the 16th of May 1782, that nobleman, seconded by Mr Horne Tooke, and Mr Pitt, was sitting in a tavern, composing advertisements of reformation for

the newspapers. MUTANTUA

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