“Sir,
Having long deferred to make any report relating to the observations that were taken at sea by captain Campbell, in the year 1757, which you transmitted to me by order of the lords of the admiralty, I think it necessary to acquaint you, that, upon examining those observations, I perceived that they were not in all respects accompanied with such circumstances as are requisite for forming a right judgment of the accuracy and certainty with which observations proper for finding the longitude at sea by the moon can in fact be taken; for which reason I delayed giving my opinion upon this point till I could have an opportunity of comparing a greater variety of observations, made at different times, and with different instruments: such an opportunity having lately been given me by captain Campbell, who has favoured me with a copy of several observations that were made by him in 1758 and 1759, I now beg leave to lay before their lordships the result of the comparisons which I have made.”

— James Bradley

Miscellaneous Works and Correspondence (1832), To Mr. Cleveland Secretary of the Admiralty (April 14, 1760)

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James Bradley 11

English astronomer; Astronomer Royal 1693–1762

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“This fundamental and most important article being established upon such full evidence, it remained to be examined within what limits the errors arising from observations actually taken at sea could be contained.
In order to determine this point, I computed the ship's longitude from each of the observations made by captain Campbell, and, upon comparing the results of several that were taken near the same time and under the like circumstances, it appeared that in general the observer was not liable to err more than one minute in judging of the apparent contact of the moon's limb and the object with which it was compared. Now this being nearly the same error that would be found to obtain, if the like observations were to be made with the same instruments on land, it may hence be inferred, that in moderate weather the motion of the ship is no otherwise an impediment in this sort of observations, than as it renders the repetition of them more tedious and troublesome to the observer, which yet ought by no means to be omitted; because if each single observation be liable to an error of a minute only, by taking the mean of five or six, the error on this head may be so far diminished as to be of small moment.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

Miscellaneous Works and Correspondence (1832), To Mr. Cleveland Secretary of the Admiralty (April 14, 1760)

“But before I proceed farther it may be proper to take notice, that since the time when I gave their lordships an account of the near agreement of Mr. Professor Mayer's lunar tables with the observations that had been then made at the Royal Observatory, I have compared several others, which concurred to prove that the difference between the observed and computed places nowhere amounted to more than about one minute and a half; and I find that the difference (small as it is) may yet be diminished by making alterations in some of the equations, whose true quantity could not be determined without proper observations; after making the needful corrections it appeared, by the comparison of above eleven hundred observations taken here since the new instruments were fixed up, that the difference did nowhere amount to more than a minute: it may therefore be reasonably concluded, that so far as it will depend upon the lunar tables the true longitude of a ship at sea may in all cases be found within about half a degree, and generally much nearer.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

Miscellaneous Works and Correspondence (1832), To Mr. Cleveland Secretary of the Admiralty (April 14, 1760)

“I would by no means attempt to infer from hence, that the longitude found by observations of this sort may in all cases be depended upon within one degree; but I beg leave to observe, that whatever extraordinary circumstances may have concurred to produce so near an agreement in this particular case, the event is such as may give reason to hope, however great the difficulties of finding the longitude by this method seem to be, that they are not insuperable, or such as ought to deter those whom it most nearly concerns from attempting to remove them.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

Miscellaneous Works and Correspondence (1832), To Mr. Cleveland Secretary of the Admiralty (April 14, 1760)

“My Instrument being fixed, I immediately began to observe such Stars as I judged most proper to give me light into the Cause of the Motion… There was Variety enough of small ones; and not less than twelve, that I could observe through all the Seasons of the Year; they being bright enough to be seen in the Day-time, when nearest the Sun. I had not been long observing, before I perceived, that the Notion we had before entertained of the Stars being farthest North and South, when the Sun was about the Equinoxes, was only true of those that were near the solstitial Colure: And after I had continued my Observations a few Months, I discovered what I then apprehended to be a general Law, observed by all the Stars, viz.”

James Bradley (1693–1762) English astronomer; Astronomer Royal

That each of them became stationary, or was farthest North or South, when they passed over my Zenith at six of the Clock, either in the Morning or Evening. I perceived likewise, that whatever Situation the Stars were in with respect to the cardinal Points of the Ecliptick, the apparent Motion of every one tended the same Way, when they passed my Instrument about the same Hour of the Day or Night; for they all moved Southward, while they passed in the Day, and Northward in the Night; so that each was farthest North, when it came about Six of the Clock in the Evening, and farthest South when it came about Six in the Morning.
A Letter from the Reverend Mr. James Bradley Savilian Proffesor of Astronomy at Oxford, and F.R.S. to Dr. Edmund Halley, Astronom. Reg. &c. giving an Account of a New Discovered Motion of the Fix'd Stars. Philosophical Transactions (Jan 1, 1727) 1727-1728 No. 406. vol. XXXV. pp. 637-661 http://rstl.royalsocietypublishing.org/content/35/399-406/637.full.pdf+html.

“You all very well know what deference I always pay, and ever will, to that part of the office of a jury which properly belongs to them. In regard to the law, I have always been as tenacious of the proper function of a Judge, as I have been of that of the jury. I never will, while I have the honour of executing the office of a Judge, attempt to controul or influence their minds in respect of damages; but only submit to them such observations as occur to me upon the evidence.”

John Eardley Wilmot (1709–1792) English judge

Wilkes v. Lord Halifax (1763), 19 How. St. Tr. 1410.

“Croton River was the only place I could find suitable to the purpose, all circumstances being taken into consideration. I wrote your Excellency what I had done, and where I was, that if you had any thing in charge I might receive your orders. I wrote you the reasons for my not waiting upon you in person were, I had many letters to answer, and many matters to regulate in my department, which prevented me from returning. Besides which, it was almost half a day's ride, the weather exceeding hot, and myself not a little fatigued. And here I must observe, that neither my constitution nor strength is equal to constant exercise.”

Nathanael Greene (1742–1786) American general in the American Revolutionary War

Letter to George Washington (July 1778)

“I observe you have thought proper to insert the last number of the Philosophical Magazine your opinion that my attempts at the safety tubes and apertures were borrowed from what I have heard of Sir Humphrey Davy's researches. The principles upon which a safety lamp might be constructed I stated to several persons long before Sir Humphrey Davy came into this part of the country. The plan of such a lamp was seen by several and the lamp itself was in the hands of the manufacturers during the time he was here.”

George Stephenson (1781–1848) English civil engineer and mechanical engineer

Letter published in The Philosophical Magazine (1817-03-13)

“There is of course no extraordinary fact resting on testimony only, of which it is not possible to presume some error in the observation or reporting, if we be set upon finding one.”

Robert Chambers (publisher, born 1802) (1802–1871) Scottish publisher and writer

Source: Testimony: its Posture in the Scientific World (1859), p. 2

“I have never yet seen any plan which has not been mended by the observation of those who were much inferior in understanding to the person who took the lead in the business.”

Edmund Burke book Reflections on the Revolution in France

Reflections on the Revolution in France (1790)

“Those observations are but foul,
Which make me wise to lose my soul.”

Henry Vaughan (1621–1695) Welsh author, physician and metaphysical poet

"Childhood".
Silex Scintillans (1655)
Context: Why should I not love childhood still?
Why, if I see a rock or shelf,
Shall I from thence cast down myself?
Or by complying with the world,
From the same precipice be hurled?
Those observations are but foul,
Which make me wise to lose my soul. And yet the practice worldlings call
Business, and weighty action all,
Checking the poor child for his play,
But gravely cast themselves away.

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James Bradley 11

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