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To enumerate all the corrections and improvements effected by Dr. M.'s Observations, would occupy more space than can be allotted to the present memoir; but the reader is referred to Professor Vince's Astronomy, and to the Philosophical Transactions.
His communications to the Royal Society, like his other productions, are particularly valuable for their great utility and accuracy. They consist chiefly of astronomical observations; improvements of mathematical and optical instruments; calculations of the eclipses of the sun, moon, and Jupiter's satellites; articles on parallaxes, light, vision, refraction, weight, measures, gravitation, &c.; also calculations and predictions of comets; together -making above thirty communications. In 1774, he went to Shehallien, in Perthshire, to ascertain the lateral attraction of that hill. In his account will be seen with what care and trouble this work, which appears so easy, was attended. He found 5, 8" the quantity the line was affected by the attraction of the mountain; thence he concluded that the density of the mountain was the mean density of the earth: the result deduced was, that the density of the earth is greater towards the centre than at the surface, which has been also proved by the measure of degrees, and by the pendulum: in fact, the density of land is four or five times greater than that of water. For this he was presented by the Council of the Royal Society, with Sir George Copley's gold medal.
In the history of science, few persons can be mentioned who have contributed more essentially to the diffusion of astronomical knowledge than Dr. Maskelyne; and perhaps no man has been so successful in promoting practical astronomy, both by land and sea. During his time, private observatories became general, though scarcely known before; nor could such be made useful without his Nautical Almanac, and other tables, except by men of extensive science, and by very laborious calculations.
He was, moreover, an improver, and also an inventor of instruments; among which may be noticed the prismatic micrometer: but though profoundly skilled in optics, and ingenious in mechanical contrivances, he always paid great deference to the opinions of opticians, and other practical mechanists.
His plans were mostly directed to substantial objects, while a steady perseverance gave an efficiency to all his undertakings; and notwithstanding his profound knowledge of physical astronomy, his attention was chiefly directed to reduce the scientific theories of his predecessors to the practical purposes of life. In this he was eminently successful, particularly in his labours for the longitude, by which he essentially contributed to the advancement of navigation, the prosperity of commerce, and the wealth, honour, and power of his country.
Dr. Maskelyne corresponded with all the celebrated astronomers of his time to be convinced of this, it is sufficient to look over the papers of the learned of all nations, which he has presented to the Royal Society.He did not write so much as could have been wished: but it is difficult for an astronomer, engaged in constant observations, with the care of the Nautical Almanac, to undertake great theoretical inquiries, in which he would be continually interrupted; he never omitted to make the most difficult and interesting observations himself, as those of the moon; trusting to his assistant only when the observations were more easy and less important. The writings he published, are distinguished by correct and just ideas, and great depth of knowledge: such is his treatise on the Equation of Time, in which he has corrected, with due attention, a mistake which had escaped La Caille, and a smaller error of Lalande.
Lalande took in good part the lesson which was given him; but Bernouilli having seven years afterwards inserted a translation of Dr. Maskelyne's memoirs, in his " Recueil pour les Astronomes," one of Lalande's pupils, (d'Agelet) took the part of his master, in a manner that might have caused a coolness between the parties concerned; but it had no effect of that kind, and the two astronomers corresponded as before. Some doubts were entertained respecting the latitude and longitude of Greenwich. Dr. M. to whom the memoir was sent, showed, with his eloquence and usual moderation, that the doubts were without foundation; but he did not oppose the means used by others to remove them
Dr. M. had good church preferment from his College; and his paternal estates, (of which he was the last male
heir), were also considerable. He married, when rather advanced in life, a young lady of large fortune, the sister and co-heiress of Lady Booth, of Northamptonshire, by whom he had one daughter, whose education he superintended with the fondest care. Dr. M. died on the 9th of February, 1811, in the 79th year of his age; his health previously declining for some months: and he contemplated his approaching dissolution with pious resignation, and with a lively hope of being admitted into the presence of that Deity, whose works he had so long studied, and so ardently admired. His favorite science tended the more strongly to confirm his religious principles; and he died as he had lived, a sincere Christian-an additional proof" that the knowledge of nature will ever be the firmest bulwark against Atheism; and, consequently, the surest foundation of true religion."
Among his most intimate friends, may be classed Dr. Herschel, Dr. Hutton, Messrs. Wollastons, Mr. Aubert, Bishop Horsley, Sir George Shuckburgh, Baron Maseres, Professor Robertson, also Professor Vince, whose publications ably illustrate Dr. M.'s labours; and whom he appointed the depository of his scientific papers.
Thus, from Dr. M.'s important labours, his public character is well known, and his fame immoveably established; but the man, the father, the friend, was truly estimable. He was, indeed, exemplary in the discharge of every duty. In his manners, he was modest, simple, and unaffected. To strangers he appeared distant, or rather diffident; but among his friends he was cheerful, unreserved, and occasionally convivial.
Dr. Maskelyne has been succeeded by John Pond, Esq. F. R. S. who was appointed Astronomer Royal, in February, 1812.
To read an account of the liberal support which has been afforded to the widows and children of the unfortunate crew of the Whale-ship, supposed to be lost in Davis' Straits, must be gratifying to every philanthropist.Though it is much to be feared that the crew has perished, yet the following narration renders it barely possible that
some may still survive. I wish not to raise fruitless expectations in the minds of the distressed; but it may afford a gleam of comfort till Time's lenient hand shall have softened their afflictions.
In 1630, three English ships were fitted out for Greenland. One of them being straitened for provisions, the master sent eight of the crew on shore to kill venison, allowing them a boat, and giving them orders to follow the ship to Green-Harbour, situated a little to the Southward of the place where they landed. Having killed 14 or 15 deer, they purposed the next day to return to the ship; but a great quantity of ice drifting to the shore, obliged the ship to stand so far out to sea as to be out of sight when they reached Green-Harbour. Knowing the ships were to rendezvous in Bell-Sound, and to leave Greenland within three days, the poor fellows began to be very uneasy lest the ships should depart ere they arrived. They thought it expedient to throw the venison into the sea to lighten the boat, and to steer, with all possible speed, to Bell-Sound, about 16 leagues to the Southward; but all being ignorant of the coast, they overshot the port 10 leagues. When sensible of their error, they returned to the Northward; but one of the company being positive that Bell-Sound lay further to the South, they sailed Southward again, till they were a second time convinced of their mistake: then bore about to the North, and, at length, arrived at Bell-Sound; but so much time had been lost, that the ships had, to their great consternation and distress, left the coast, and sailed for England.— These unfortunate creatures stood gazing on each other, amazed at the distress to which they were so suddenly reduced, being provided with neither food, fuel, clothes, or house, to shield them from the inclemency of so rigorous a climate. Their perplexity being somewhat abated, they began to devise the most proper means to support life during the approaching winter, in a country within 12 leagues of the pole; being the first that ever did inhabit it the year round: and, perhaps, there is no instance in history, of a company of men, in such exquisite distress, that showed more courage and patience, or made a wiser provision for their preservation. In the first place, they agreed to go to Green-Harbour, where
they arrived in twelve hours; and having provided nearly twenty deer, and four bears, returned to Bell-Sound; where fortunately was erected a large booth, for the use of the coopers in the fishing season; the length of which was 80 feet, and breadth 20, covered with Dutch tiles: within' this they built another, whose length was 20 feet, breadth 16, and height 10, so contrived as to admit as little external air as possible. They provided themselves. with wood, which they stowed between the beams and roof of the greater booth.
On examining their stock of provisions, they were convinced that it would scarcely serve them half the winter; therefore, they stinted themselves to a meal each day, agreeing to keep Wednesdays and Fridays as fast-days, relying on Heaven to alleviate their distress; and redoubled their prayers, for strength and patience to endure the trial. By the 10th of October, the nights had become long, the weather very cold, and the sea frozen over; and having no business to divert their gloomy thoughts, they more than ever reflected on their miserable condition; but, they received great consolation from fervent devotion.Having again surveyed their provisions, they agreed to have each week, three meals of venison and bear, and four of fritters, or greaves, which is very loathsome food, being only the scraps of the fins of whales, thrown away after the oil has been extracted.-Lest they should want fuel to dress their food, they thought it adviseable to roast more at a time, and stow it up in hogsheads. It being now the 14th of October, the sun had left them; but they had the moon both day and night, though much obscured by clouds and foul weather; there was also a glimmering kind of day-light, for eight hours, the latter part of October, which shortened progressively till the 1st of December; from which, till the 20th of the same month, they could perceive no day-light at all, being now one continued night. To procure light within doors, they made three lamps of some sheet lead found upon one of the coolers, and there happened to be oil enough to supply them, left in the cooper's tent; for wicks, they used rope-yarns.These lamps were great comfort to them in that long