Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/274

Rh 262 NAVIGATION of the royal observatory at Ma de Leon is placed 24 m 47 s- 5 west of Greenwich. In the English almanac for 1883 it is given as 24 m 49 S 6; therefore they were very near the truth in 1791. The almanac for 1810, published at Madrid in 1807, was the first in which the lunar distances were reduced to the meridian of Isla de Leon that is, giving the distance to the even hours 3, 6, 9, 12, &c. The Spanish almanacs for 1813 to 1816 were published in Fleet Street, the first-named only one year in advance. From 1820 to 1832 they were good octavos and clear type. Soon after that time they appeared in folio, giving nearly all the information found in the English almanac, but not neglecting the saints days and festivals. The excellent Berlin Astronomisches Jakrbuck began to appear in 1776, the American Ephemeris in 1849. These two epheme- rides and the French Connaissance des Temps are inde pendent and valuable works, and for astronomers at least in some respects superior to the English Almanac. After Maskelyne s death the correctness and reputation of the Nautical Almanac underwent a serious decline. The matter came before parliament in 1818, when the board of longitude was reconstructed, and the old Acts consolidated. Dr T. Young was appointed secretary to the commissioners, and superintendent of the Almanac. Ten years later, in 1828, the board was swept away, the Almanac was placed under the Admiralty, and Young, with Faraday as a chemist and Sabine as a practical observer, were appointed scientific advisers to the Admiralty, which ever since has spent a certain annual sum on scientific research. The Almanac still gave cause for dissatisfac tion ; a memorial to the House of Commons, dated January 28, 1829, states that the Nautical Almanac was for the good of astronomy as well as navigation, and that it is so declared in the first Almanac in 1767 ; that in 1818 fifty- eight errors were discovered, and a similar number in the Almanac for 1830, and that it had not kept pace with navigation or astronomy ; that it did not give the moon s distance from the four principal planets as the Portuguese and Danish ephemerides did, nor did it give the positions of those planets ; that there was no list of the occultating stars which were ascertained to be visible in Halley s time, but were neglected after the invention of Hadley s sextant (they were in the Milan ephemerides); and that the tables of the sun were not correct. This was supported by a paper signed by J. F. &quot;W. Herschel, read at the board of longitude April 5, 1827, which stated that the moon s meridian passage was not given at all, that of the sun roughly to the nearest minute. The right ascension and declination of the larger planets were not given with accuracy, as they should have been, as their theory was perfect. The moon s right ascension in time and hourly motion should have been given, also the time of semi- diameter passing the meridian, for use with moon-culmin ating stars. Young replied to this memorial and main tained that the fifty-eight errors were exaggerated ; forty of them were in reality only one in the moon s place, which Tvould put a ship out 5 miles, and which was corrected in the next year s book, &quot; which every accurate navigator is bound to consult, to guard against possible minute acci dent.&quot; The errors of 1830 were, he says, of less import ance : the French Connaissance des Temps of 1821 was corrected by the English Almanac; some errors were found in Taylor s logarithms ; the error in the solar tables, said to be 15 seconds, vas really only one. The ultimate result of these controversies was the appearance of the new and reformed Nautical Almanac in 183-4. It may be added that the last remnant of the old laws, the protection of the Almanac against competition by a penalty, was abolished by an Act passed August 6, 1861. The number of copies of the .Nautical Almanac (for 1851) printed in 1847-48 was 10,000, and the number sold (of various years) 8638, at 5s. each; the gross produce of sale was .2159, and the expense of preparation 3677. In 1882 15,071 copies were sold, of various years, extending to four years in advance ; the cost was 3368, and the gross produce of sale at 2s. 6d. each 1900. The sale of the Nautical Almanac has lately decreased on account of the amount of information given in private publica tions. Prior to 1795 the nautical portion of the British com munity, including the royal navy, were entirely dependent upon private industry and enterprise for charts and sail ing directions. On August 12th of that year an order in council placed all such articles as were then in the posses sion of the Admiralty in charge of Mr Dalrymple, an eminent publisher of such things, who had long been employed by the East India Company, and whose catalogue in 1786 contained 347 charts between England, the Cape, India, and China ; l thus the germ of the hydrographic department was established. The expense was then limited to 650 a year, just one-tenth of what was allowed last year for drawing and engraving charts alone, besides 5500 for printing and mounting them. In 1881 there were 118,542 charts sold. After the close of the long devastating war in 1815 both trade and science revived, and several Governments besides that of Great Britain saw the necessity of surveying the coasts in various parts of the globe ; the greater portion of the work fell to the English hydrographical department, which took under its charge nearly every place where the inhabitants were not able to do it for themselves. The parts which received immediate attention were the shores of the United Kingdom, the lakes of Canada, Gulf of St Lawrence and Newfoundland, West India Islands, Sicily and the eastern part of the Mediterranean, west coast of Africa, Australia, Tierra del Fuego and Straits of Magellan, Arabia, Persia, Bay of Bengal from the Hooghly to Malacca Strait, and the Red Sea. Similar good work was carried on by the Governments of France, Norway, Denmark, Sweden, and Russia ; Portugal was an exception. Spain had for her own shores the excellent work of Admiral Vincent Tofino, performed in the latter part of last century. The United States of America have surveyed both shores of that continent since 1832. Since 1837 the British surveyors have been continually employed in Australia and New Zealand, and since 1842 on China and Japan, and the whole west coast of America from Magellan to Behring s Straits. British Columbia has been surveyed in detail, also the great barrier reef of Australia and Torres Strait, the coast of New Guinea and the Fiji group, coast of Arabia, and Persian Gulf. The Gulf of Suez and other parts of the Red Sea have been resurveyed. Fresh require ments are continually springing up, and greater precision is expected in the surveys, which are now continued, with the same zeal and unremitting attention, under the present hydrographer Captain Sir Frederick Evans, K.C.B., to whose paper for the British Association (1881) the reader is referred. The first official catalogue of charts was issued in 1830 ; the total number was then 962. In 1880 the number had increased to 2699. The greatest increase was on the British coasts, from 51 to 368, the Arctic seas and north-east coast of America, from 57 to 302, and the Pacific Ocean islands, from 11 to 100. The question of the accuracy with which the sea charts now represent a portion of the globe is entirely set at rest by the possession of a correct knowledge of the figure and 1 In 1783, in an excellent descriptive work of the nature of sail ing directions, Dalrymple with clear prevision gave his opinion that chronometers would so change geography that new charts would be required.