1023-43 TO THE READER. THE within work contains important information, on a great variety of subjects, interesting both to the merchant and mariner; being the result of forty years' experience of a seafaring life, during twenty-eight of which the author has been actively employed as master of vessels. I have given rules and examples for working lunar observations, and for correcting the errors of the Sextant, illustrated by figures; also a short and easy method of clearing lunar distances from the effects of parallax and refraction, without any difference of cases, the correction being always applied the same way-invented by myself. On the Thermometer, its use in navigation, particularly in the neighbourhood of the Florida Stream, and on which it may be dangerous to rely on its indications. General remarks on the Gulf Stream, dictated by twenty-seven years diligence and experience of the author: an imperfect knowledge of the variations of this stream, has proved fatal to many. Various subjects on Natural Philosophy, useful to navigators, &c. The different subjects are found in the con tents. The safety of commerce depends much on the improvement of navigation, and at the same time contributes to increase the wealth of our merchants and the public revenue. When finding the latitude was in its infancy, great accuracy was required, and many years elapsed before the method of taking correct altitudes of the sun was generally established; only persons distinguished for their skill and perseverance could follow the examples of learned men, who first taught them the art: at present, sailors before the mast can take altitudes; and, it is hoped, in the space of a few years, they may be able to take distances. The keeping an exact reckoning, and being versed in the lunar observations, is of the first importance, the neglect of which not only affects the reputation of the mariner and the safety of the ship, but has caused the loss of many valuable lives and the ruin of numerous families. A proper experience in these matters should be the chief concern of those who undertake the navigation of a ship, whereby the lives and fortunes of Presented by 2. S. Mitchell THE AMERICAN PRACTICAL LUNARIAN, AND SEAMAN'S GUIDE; CONTAINING 1. An explanation of the principles by which the longitude is deduced from lunar observations. 2. On Lunar Observations.. 3. On finding the longitude by Chronometer, and ascertaining its rate. 4. On the Sextant. 5. On the Thermometer-its use in navigation, 7. On the Marine and House Barometer, its use 3. On the Hygrometer. 12. Astronomy. 13. Sailing directions for the Madeiras, Cana- 14. Directions for sailing round Cape Horn, 15. Practical Seamanship. 9. On the causes of the errors of the Mariner's 17. Stratagems for escaping from the enemy at Compass. 10. On Magnetism. 11. On Electricity and the Lightning Chain and Rod. sea. 18. Several sketches of trade not generally ILLUSTRATED WITH PLATES. TO WHICH ARE ANNEXED, A COMPENDIUM OF MARINE LAW, AND Mercantile Regulations and Customs; BEING A CORRECT AND USEFUL GUIDE TO ALL MEN IN BUSINESS, ESPECIALLY THOSE MARINE INSURANCE LAWS: THE DUTY, AUTHORITY AND RESPONSIBILITY OF MASTERS OF VESSELS, COMMERCIAL FORMS. BY THOMAS ARNOLD. PHILADELPHIA: PUBLISHED AND FOR SALE BY ROBERT DESILVER, No 110, ALSO FOR SALE at no. 295, sòUTH FRONT STRRET. August-1822. |