[6] It were much to be wished that navigators would be more cautious in laying themselves open to a similar censure. On looking hastily over a map of the world we see three Melville Islands, two King George’s Sounds, and Cape Blancos innumerable. [7] Young. Lectures on Nat. Phil. ii. 627. See also Phil. Trans. 1801-2. [8] Captain Basil Hall, R. N. [9] We must caution our readers who would assure themselves of it by trial, that it is an experiment of some delicacy, and not to be made without several precautions to ensure success. For these we must refer to our original authority (Fresnel. Mémoire sur la Diffraction de la Lumiere, p. 124.); and the principles on which they depend will of course be detailed in that volume of the Cabinet Cyclopædia which is devoted to the subject of LIGHT. [10] Little reels used in cotton mills to twist the thread. [11] Such a block would weigh between four and five hundred thousand pounds. See Dr. Kennedy’s “Account of the Erection of a Granite Obelisk of a Single Stone about Seventy Feet high, at Seringapatam.”--_Ed. Phil. Trans._ vol. ix, p. 312. [12] Dr. Coindet of Geneva. [13] Journal of a Voyage to the South Seas, &c. &c. under the Command of Commodore George Anson, in 1740-1744, by Pascoe Thomas, Lond. 1745, So tremendous were the ravages of scurvy, that, in the year 1726, admiral Hosier sailed with seven ships of the line to the West Indies, and buried his ships’ companies twice, and died himself in consequence of a broken heart. Dr. Johnson, in the year 1778, could describe a sea-life in such terms as these:--“As to the sailor, when you look down from the quarter deck to the space below, you see the utmost extremity of human misery, such crowding, such filth, such stench!”--“A ship is a prison with the chance of being drowned--it is worse--worse in every respect--worse room, worse air, worse food--worse company!” Smollet, who had personal experience of the horrors of a seafaring life in those days, gives a lively picture of them in his Roderick Random.