Wrinkles in Practical Navigation

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1904 edition. Excerpt: ...pounds; it should be of the kind known as " keyless," or what the Americans call a " stem-winder." After breakfast all the clocks on board should be set to Apparent Time proper time at Ship for noon of that day, as determined in advance, by working up the of regulating dead reckoning. There is thon no fear of missing "sun time," and the plan locls on for many reasons is preferable to the usual one of making eight bells by the sun. For example, when steering near North or South in the fly-away steamers of to-day, it would shew immense ignorance to wait till the sun had "dipped" and take the maximum reading as the meridian altitude. It does not require much "sawee" to see that near the meridian the Sun and ship apparent " rise " due to speed of ship will exceed the real " rise," and that up approaching to a certain point it will neutralize the subsequent drop. By the time this eac ot er' point has been attained it may be several minutes after the meridian passage, and the sun may bear several degrees to the westward. With the moon it is still worse, since her rapid motion in declination must be taken into account. When the sun is crossing the equator, his hourly change in declination is only 1', but the moon's is 18'. Take the case of a "20-knotter " in latitude 50 N., steering towards the moon, which is crossing the equator northwards. They will approach each other at the railway speed of 38', and the maximum altitude will exceed the meridian altitude by very nearly 3f, and will occur at Hi minutes after the time of meridian passage. This is one reason why the moon is tabooed in "Wrinkles." The author notices with amusement that certain of the...