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in question.* How well they have merited that. degree of confidence is left to the impartial world to determine.

To return again to Mr. Maskelyne's account: he, as I think has been already shown, having said and done every thing in his power to the dishonour and discouragement of my Invention, scruples not to sum up his opinion of it in the following terms:

"That Mr. Harrison's Watch cannot be depended 'upon to keep the Longitude within a degree, in a 'West India voyage for six weeks, nor to keep the 'Longitude within half a degree for more than a fortnight, and then it must be kept in a place

* Not always so, for in the discussions which took place between them and the younger Harrison, the Professors gave much cause to doubt their proficiency as practical astronomers: and it has been shown it was usual to call in Captain Campbell to decide disputed points. The opinion of that Officer, it is remarkable, was always in favour of the Mechanic.—If they ventured, on their return to College, to relate how they were discomfited by this nautical Umpire, it is likely it would produce some scenes which a Sterne, or a Moliere, was wanting to preserve.

† That Dr. Maskelyne should have suffered this assertion to escape him, and yet without adverting in a note, or otherwise, to the tangible logic, that in two voyages (or four) the Timekeeper had bona fide performed with an accuracy directly at variance with such a declaration may well occasion it to be asked, why philosophers must think it necessary to despise the hearty contempt of the vulgar; when, as it may happen, and as it does happen here; any sailor who had belonged to the Deptford, the Merlin, or the Tartar, though he could neither read nor write, and although his reasoning was confined to the

'where the Thermometer is always some degrees 'above freezing: that, in case the cold amounts to

adage, which says, the proof of the pudding is in the eating of it, would have been more approved by Bacon and Locke, above all by Newton, than the mathematical triflers who had the assurance to sanction this miserable proof of the superiority of the Lunar method, which in effect is the sum and drift of the whole purpose. We may add that in England, where a wager so frequently settles a dispute, the Gentlemen of the Jockey Club would immediately have taken three, four, or five to one, on the result of as many trials of the machine, under the care of some competent person, not a zealous bigot to the Lunar process, as was the case in the trial commented on.-Not long after the present affair, Dr. Maskelyne published a very large quarto of "Tables of Refraction and Parallax," highly creditable to his industry and professional researches, but equally a proof of his infatuation, in expecting masters of merchantmen, as well as the gentlemen of the navy, to conform to such complicated rules for finding the situation of their ship. Yet he says that "Lunar observations are now happily understood and "practised, with the help of the Nautical Almanac, both in "the Navy and the Merchants service."-That there is here and there a mercantile Captain accomplished enough to conform to these purposes,* is true, but they form an exception

* One of these (Captain William Collinson, the younger) stated to the Author, that with all possible care, and under the most favourable circumstances, he could not avoid an error equal to thirty miles. It would be a great mistake to imagine they prefer Lunations to a Timekeeper. On the contrary their opinion, in coincidence with that of his lamented friend, the reverend John Barnes Emmett (one of the best astronomers we had) is that the proper use of observations, when they can be had, is for the correction of any casual irregularity in the chronometers on board their ship:—but as this would have been assigning them only a secondary place, in utility, Dr. Maskelyne would sooner have parted with his dexter hand than affixed his signature to such a heterodox article of mechanical belief.

'freezing, the Watch cannot be depended upon to 'keep the Longitude within half a degree for more to the aggregate of those commanders, among whom there are deficiencies so great, that at Hull, one of the four great seaports of the kingdom, the Author is well assured there are Masters who do not know how to calculate their Longitude by the chronometer, as simple as it is, but adhere to the exploded practice by the log; with the addition of the alliterative maxim, "lead, latitude and look out." Those people, who after rise from before the mast, if they acquire a character for sobriety and diligence, are seldom troubled with the enquiries of the shipowner, concerning their ability to discuss the Astronomical Ephemeris, much less to know their acquaintance with the ponderous volume of tables (just spoken of.) Even when they are qualified to avail themselves of the Astronomer's vigils in their behalf, they know what the occupant of Flamstead Hill, with invincible pertinacity, affected to conceal from himself,— that a clouded sky, or an unsteady vessel, may serve only to illustrate the precariousness of every thing on earth, or in "the great sea-deeps." Waiving this, however, we remember the opinion of an experienced naval Officer; which was that the Tables might be of some use in long voyages, but not in short ones, because the voyage would be finished before the observations would.

In the preface of his reply to Mr. Mudge, the Doctor warmly attacks a certain German, Professor Zach, for what? -for sacrificing Astronomy to Timekeepers!-Thus it is, the learned and the ignorant equally illustrate the observation, how much easier it is to detect the mote in your neighbour's eye than to feel the beam in your own. For what was the main drift of the trial concerted between the Sardonic confederates (Lord Morton and himself) but to sacrifice Timekeepers to Astronomy?-and that too in contravention of the notorious fact, that the Astronomers had been completely beaten at sea. To decide that the Mechanics were entitled to a secondary and

'than a few days, and perhaps not so long, if the 'cold be very intense: nevertheless, that it is a 'useful and valuable Invention, and in conjunction 'with the observations of the distance of the Moon 'from the Sun and fixed stars, may be of consider'able advantage to navigation.*

subordinate place only, after such unanswerable evidence that they had a right to the first distinction, directly tended to make the authority of the Board (and his own) no more respected among seafaring men than the judgment of a mountebank would be. And this "sacrifice of Timekeepers to Astronomy" would not unsettle the belief of those who value an ounce of experience more than a hundredweight of hypothetical demon

strations.

*At every turn men are met with who remind us of the old notion of a town about to be beseiged; when it was consulted how to fortify it; and the mason, the carpenter and the currier advised each as best suited his interest. Perhaps this common place has seldom been better illustrated than by the pertinacity with which the Astronomer Royal gives his own craft the preference. How he could impliedly assume as if he actually did not know, that in the outrun to Jamaica the error of the Watch was little more than a mile; while in his own pamphlet, "The British Mariner's Guide," he does not undertake for the Longitude nearer than sixty miles. How, after such tangible evidence, he could, on the strength of the present surreptitious trial (which is preceded by no certificate that the Watch was properly prepared) come to the conclusion seen here, suggests no better answer than that, instead of being authorized by the Board of Longitude (and of Latitude) to publish his proceedings, that Board if it had not totally swerved from its purposes, might have been justified in reporting him a fit subject for a writ de lunatico enquirendo: for it is, in effect, a new version of Lord Peter's assertion, in Swift's tale-when

Having sufficiently refuted the first part of the opinion already, it only remains for me to make such remarks on the Lunar method of finding the Longitude, as this coupling of my Invention with it seems to call upon me for.

It is with reluctance that I follow Mr. Maskelyne into a subject in which I may seem, like him, to be actuated by a selfish preference to my own scheme; however, as I shall give my reasons for what I advance, I will not hesitate to submit them he swears that the crust is good mutton. It reminds us, however, of a Colossus of ambition, "damn'd to everlasting fame', who, after all his plans were overthrown on the memorable field of Waterloo, more decisively than those of Charles XII. at Pultowa, had the weakness to demonstrate on paper, illus

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trating it with a diagram of six V's [A] that by all the rules

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of the art of war he ought to have had the victory; and, as if emulating the Astronomer, he would needs try to demolish the reputation of his rival, to plant his own statue on the ruins!

The affair between Mr. Mudge, junior, and the Astronomer Royal, gave occasion for a curious and important illustration of the superiority of mechanism being appealed to, by the former. Admiral Campbell was on his return from Newfoundland, with a fleet of men of war; and, having a Timekeeper by Mudge with him, carried a press of sail in the night as they were approaching the Scilly Rocks to the great dismay of the other Commanders, who, their reckonings being up, were in dread every moment of the fate of Sir Cloudesly Shovel.—It is almost superfluous to add that this Officer, who, we learn from Dr. Maskelyne was a skilful astronomer, would certainly never have thought of placing the same dependance on the best Lunar observation he could get: if the Moon was not then in her zenith at the antipodes.

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