John Harrison

“ The Longitude of any Place is its Distance East or West from any other given Place; and what we want is a Method of finding out at Sea, how far we are got to the Eastward or Westward of the place we sailed from. The Application of a Time-Keeper to this Discovery is founded upon the following Principles: The Earth’s Surface is divided into 360 equal Parts (by imaginary Lines drawn from North to South) which are called Degrees of Longitude; and it’s daily Revolution Eastward round it’s own Axis is performed in 24 Hours ”

“ From the Benefit of the first Objection (even if it was founded in Truth, which I utterly deny) the Commissioners have surely precluded both themselves and the Nation, as with Respect to me, by their repeated Orders and Instructions, and after leading me on for near Half a Century, to employ my whole Time and make long Voyages for perfecting the Invention, they can never be permitted now to come and say the Invention itself is good for nothing. ”

“ The Lunar Tables, for which the Rewards have been given, are calculated to shew the Distance between the Sun and Moon, or Moon and Stars, at Greenwich; I admit the Practicability of making such Tables; but with Regard to the other Requisites, I beg Leave to observe that, for six Days in every Month, the Moon is too near the Sun for observing, consequently, during those Days, the Method falls totally to the Ground; that for about other thirteen Days in every Month, the Sun and Moon are at too great a Distance for observing them at the same Time, or are not at the same Time visible ”

“ Moreover I am ready, on Condition of receiving the Remainder of what’s due to me, upon Oath to give all manner of future Information and Instruction in my Power; and I hope it could never enter into any Man’s Idea of general Practicability, that I should actually teach every indifferent Workman in the Nation, and furnish each of them with a Set of Tools for the Trial of his Ability, at my own Expence, before I could be entitled to the Reward. ”

“ If our Rivals in Commerce and Arts should rob us of the Honour as well as the first Advantages of the Discovery, I hope it will be admitted that the Fault is not mine: And I likewise flatter myself that I have now furnished sufficient Materials for the Justification of my Friends, and for shewing that the Cause which they from publick spirited Motives had the Goodness to espouse, was not unworthy of their Patronage. ”

“ Upon the Faith of this, my Son went the Voyage to Barbadoes, in which the Watch kept its Time “considerably within the nearest Limits of the Act of Queen Anne,” as certified, even by the Commissioners themselves. ”

“ Maskelyne Astronomer Royal, under the Authority of the Board of Longitude, manifestly tending, by the Suppression of some Facts and the Misrepresentation of others, to impress the World with an unjust Opinion of my Invention, and falsely asserting that my Watch did not at certain Periods therein mentioned keep Time with sufficient Exactness to determine the Longitude within the Limits prescribed by the Act of the 12th of Queen Anne ”

“ Kendall afford no solid Reason for the Commissioners to refuse lending it to me.
[6] In the fifth Volume of M. De La Caille’s Ephemerides, Page 31, he says, “that any Person would be in the wrong to suppose that the Longitude at Sea can be determined by the Moon, to a less Error than two Degrees, let the Method which is employed be never so perfect, let the Instruments, of the Sort now in use, be never so excellent, and let the Observer be the most able and accomplished. ”

“ Now ’tis obvious that while the Air surrounding the Thermometer might be very temperate, there might, if the Sun shone upon it, be a heat in the Box, superior to what was ever felt in the open Air in any Part of the World; and perhaps greater than any human being could subsist in, and consequently improper, or at least unnecessary for this experiment. ”

“ It also requires (and this perhaps when a Ship is in a high Sea) the Distance of the Moon and Star, in order to come at which, the Image of one of them must be reflected through a silvered Glass, and the other seen through an unsilvered Part of the same Glass; and they must be brought into Conjunction in the Line that connects the silvered and unsilvered Parts, and this to an Exactness only true in Theory, for an Error of a Minute of a Degree committed in this Observation, will mislead the Mariner Half a Degree in his Longitude ”

“ Maskelyne, to deliver an Opinion on this Point, I shall declare what I believe very sincerely, [28] that by far the greater Part of the Commissioners are perfectly innocent of the Treatment I have met with: most of them are Commissioners by Virtue of great Employments which engage their Time and Attention: A Board so constituted is continually changing ”

“ The Price of common Watches, where each Part is made by a different Workman, bears no Proportion to what must necessarily be [27] charged by any Man who was to make the whole with his own Hands: the same Reduction will naturally take place when a Number of Workmen are instructed to make the different Parts of these. ”

“ Maskelyne’s Knowledge of the Theory of Astronomy; as for any Thing I know to the contrary, it may be of the very first Rate, especially as the Commissioners have thought proper to entrust him with the Execution of [12] their commands; and which he has ever been as ready to undertake: But alas! as to his skill in Mechanics, he knows little or nothing of the matter he has ventur’d to take in Hand. ”

“ He was to be paid for every Thing before-hand, and to begin in a Twelvemonth after making the Bargain; he is to make Parts like Parts, but is not to be answerable for his Watch’s going at all. My Timekeeper is now in his Possession, tho’ he is not yet ready to make Use of it; There are some Parts in the making of which the Model can be of little or no Use to him; I only desired it for six or eight Months, and am confident he can have no Occasion for it before that Time is expired: however I have offered to have it forth coming whenever Mr. ”

“ Mr. Maskelyne next tells us of an irregularity which he says happened in cold Weather, and says, “However, it seems in general that the Frost must have been the [10] cause of these irregularities, as well as of the Watch’s going so much slower in the Month of January, than it had gone before.” Mr. Maskelyne ought along with this, to have published what I told him when I explained it; that the Provision against the effects of Heat and Cold was not in this Machine extended to all Degrees ”

“ Should any one however continue to propagate such an Opinion, I beg leave, in Contradiction to it, to offer that of Sir Isaac Newton, and that [26] of Martin Folkes, Dr. Halley, Dr. Smith, Mr. Graham, and eight other Persons of great Eminence, both publicly given to the House of Commons and to be found in the Journals, viz. ”