Memoirs of a Trait in the Character of George III. of these United Kingdoms/Appendix 3
VOYAGE, IN THE DEPTFORD MAN OF WAR, TO MADEIRA, AND FROM MADEIRA TO JAMAICA—ACCURACY OF THE TIMEKEEPER; AND THE RETURN, WITH A VERY TEMPESTUOUS PASSAGE, IN THE MERLIN SLOOP.
The circumstances attending the run from Portsmouth to Madeira, in the first voyage, which appeared in the Gentleman's Magazine, and other periodicals of the time, were very remarkable (and certainly such as could never have been paralleled, had the Longitude depended on Dr. Maskelyne's superior method.) When the Deptford approached the Latitude of Porto Santo, the crew who were confident in their reckonings, made her considerably to the eastward of that Island, which differed widely from the Longitude shown by the Timekeeper. But the Captain, though he would have laid five to one that the ship was too far run easterly, yet, as if out of courtesy, would not alter his course, Mr. Harrison having declared, that if the wind and weather continued the same, and Porto Santo was accurately laid down in the maps, they must see it the next morning—a prediction which was verified at seven o'clock.
On arriving in Funchal roads, another and forcible illustration of the utility of the Timekeeper occurred: for they fully expected to have found that the Beaver sloop of war had anchored there a week or two previously: that ship having sailed a fortnight before them, taking out orders to the merchants there, on account of Governor Lyttleton. It appeared that her officers and crew, being deceived in their reckoning, and imagining themselves to the eastward of Madeira, when they were in reality to the westward, lost so much time in correcting the consequences of this mistake, that they did not arrive till three days after the Deptford.
The want of the original Journal of William Harrison, is happily supplied, in a considerable degree, by an account of the voyage after leaving Madeira, which he sent to his father-in-law, about a week from his arrival at home. It is dated, London, April 10th, 1762. The details will not be thought tedious, by those who interest themselves in this first regular experiment to solve a problem which had so much excited the attention, and exercised the ingenuity of scientific men in the preceding centuries.—The beginning and the conclusion of this letter, being wholly of a family nature, are omitted: passing by this, he proceeds—I have but little time, and my voyage home has been such a one as tongue cannot utter, nor pen express; therefore it will be but a very imperfect idea that I shall be able to note down; but I thank the Almighty God, that he hath through his infinite goodness given me once more an opportunity to write to you from this place (which some time ago I never expected) and at the same time to crown me with greater success than could any ways be imagined, considering what we have undergone.
My Wife some time ago sent you a copy of a letter I wrote to her from Madeira, which gave you an account of my voyage to that place, and of the success of the Watch; so that I shall now only give you the particulars of the voyage from that Island to Jamaica, and from Jamaica to England again. We sailed from Madeira on the 18th of December, and saw no land till the 11th of January; when about half an hour after six in the morning we saw the Island of Deseada. In our voyage from Madeira to this place my reckoning by the Watch was kept a secret; for we found, was it known, that all the reckonings in the ship would be corrected by it, if I made it public. Therefore Captain Digges, Mr. Robison (who was the Gentleman sent along with me) and myself, agreed that nobody should know the account the Watch gave but ourselves, till we should be near making land. On the 10th of January, in the afternoon, I had a very good observation; and, according to the Watch, and supposing the wind to continue to blow as it then did, we should see the Island of Deseada next morning, about ten o'clock; and the Captain and I agreed that this afternoon (being the 10th) I should tell all the Officers where we were by the Watch, and that I expected to see the land next day. Accordingly I stated so, which very much surprised them; for, according to the nearest of their reckonings they were one hundred and fifty miles further from the Island than I was: but they did not at ail dispute my being right, I having already given them an instance of it at Madeira. Accordingly about half-past six o'clock in the morning of the 11th, we saw the land; which was only about three hours sooner than I expected. The correctness of the Watch amazed them very much.—[The Islands of Guadaloupe, Antigua, Montserrat, Rockdondo, Nevis and St. Christophers, Eustacia and Saba, Hispaniola and Albovato, are severally mentioned, with the dates on which they were in sight, but as it was not necessary to appeal to the Timekeeper, we pass on.] On the 18th, about twelve o'clock at noon, we saw the Island of Jamaica, and on the 19th, about five in the afternoon, we came to an anchor at Port Royal.
On the 20th we went on shore to fix on a proper place to make the observations for trying the correctness of the Watch; but it was the 26th before we got a proper place built up; when we got a good observation, and found that the Watch in all this time (that is, since the last observation at Portsmonth) had erred two minutes and thirty-six seconds, in ten weeks: which answered the purpose just as well as if it had been entirely correct.
On the 27th of January, at five o'clock in the evening, I took the Watch on board the Merlin sloop of eighteen guns. Captain Bourke, who was under orders to sail express for England; and accordingly at five in the morning of the 28th, they weighed and sailed out of the harbour of Port Royal. [Here the writer notes in their order, the Islands of Navasa, Hispaniola, Cuba, Tortuga, Hencago, Achilles's Keys, Fortune and Crooked Island, and continues] In the evening, February 10th, we saw Bird Island; and from that time till the 24th of March we saw no land, nor did we expect to see any, and we then, according to my reckoning by the Watch, made the Lizard within ten miles of what I expected.—I have already observed to you, that the Watch made an error of two minutes and thirty-six seconds in going to Jamaica; which error I could easily account for, as it is not in so perfect a state as we could make it; but the Commissioners wanted to know what it would do in its present state. This error was occasioned by the motion of the ship causing the balance of the Watch to vibrate somewhat slower, which would affect its going in proportion. It was a part that we had not quite adjusted, as we declared to the Commissioners before I went to Jamaica, so that they as well as ourselves believed it would go somewhat too slow, when at sea: and consequently the more the ship was tossed, the slower it must go, if its going was uniform in other respects. And as we had the most turbulent passage home that was possible; in consequence it went slower than in the voyage out; I supposed that would be about double as much, and accordingly found it so. But to all in the ship it was the greatest miracle that it kept going at all; for I was obliged to place it in the cabin, quite astern, upon the seat or counter; and when we lay to, which we were very often obliged to do, under a balanced mizen, it received such a shock from the breaking of the waves under the counter, that it was just the same as if I had taken the box in my hand and thrown it from one side of the cabin to the other. Had I placed it nearer the midship, it would not have undergone what it did with respect to motion, but then it would have been worse upon another account; for it would have proved impossible for me to have kept the salt water out of it, which was the reason of my placing it where I did. For that, as the Captain told me, was the driest place in the ship; yet it was far from being dry, for sometimes when a sea struck us, the water would spurn [spume] in at every seam, and it was not rare to have two feet of water upon our deck, and six inches in the Captain's cabin. Seven or eight times we sprung a leak, but through God's mercy we as often got it stopped, though sometimes we had a great deal of pumping first, and it was as much as we could do to keep our ship above water. We broke our rudder in a hard gale, but it pleased God to send us three or four hours of moderate weather to mend it again. And then came on the heaviest gale that ever man on board had seen; we had nothing to look to, but that every wave, as it came, would carry us to the bottom; but thank God, it was not to be so. We were near six weeks without an inch of dry deck; and half that time never had a topsail set for two hours together; and all that we could do was to lie to under a balanced mizen and reefed mainsail, or to scud under a reefed foresail, our topgallant masts and yards being taken down, and our topmasts lowered, with our topsail yards upon the cap.—I could give you a longer history, but time will not permit, as I am very busy getting a Committee. [He means a Board of Longitude.]
- In a printed account of the voyage, it instated in addition, that the reckonings of some of the ships in the convoy, differed no less than five degrees from that by the Timekeeper.
- Being writing to a person not much conversant with the subject, he has not mentioned and deducted the rate of going for the time.
- If we understand, by this word, the predominant party at the Boards which would be proper enough, their motives for wanting "to know what the Watch would do in its present state," although the young man does not appear to question them, at this time, were not very candid; for if they desired the trial should succeed to the fullest extent, would they not have advised the Candidate to make his work as perfect as he could. Had the Timekeeper, from some imperfect adjustment, failed to come not only within the least, but the greater limits prescribed, they would have congratulated him on its performance being so nearly within the terms of the Act, and expressed their belief that, but for the circumstance mentioned, it would have become entitled to £20,000; but then they would have sung out, that since it had resulted otherwise, it was out of their power to offer him more than another trial when he should be prepared for it. Now it turns out that, about this time, the reverend Nevil Maskelyne, B.D. afterwards (at Barbadoes) the avowed rival of the Candidate, was making a private voyage to St. Helena, in a merchant brig, furnished with Professor Mayer's Tables, which had been imported in 1756, to find the Longitude by the Moon—a step then unknown to the Harrisons, and which it becomes exceedingly difficult to acquit the mathematical Commissioners of contributing to the expenses of, out of the funds at their disposal, unless some unknown scientific character was assisting in this cross-purpose; for there is no voucher that the young Astronomer's private fortune was likely to encourage him to such an enterprize.