58 



ATLANTIC OCEAN, HYDROGRAPHY OF. 



the north pole, when the declination will be 

 89 32' 23." The star, he says, will reach 89 

 about the year 1944, and be for about 300 years 

 within a degree of the pole. 



Medals. The gold medal of the Royal As- 

 tronomical Society of England was awarded on 

 Feb. 10, 1888, to Prof. Arthur Auwers, for his 

 re-reduction of Bradley's observations. At the 

 April meeting of the National Academy of 

 Sciences of the United States, the Draper As- 

 tronomical Medal was presented to Prof. Ed- 

 ward C. Pickering, Director of the Harvard 

 College Observatory. At the same meeting 

 the Lawrence Smith Medal for original work 

 on the subject of Meteorites, was awarded to 

 Prof. Hubert A. Newton, of Yale College, New 

 Haven, Mass. 



Bibliography. A large number of valuable 

 papers have been printed in the serial publi- 

 cations devoted to astronomical knowledge, 

 and during the year the following books have 

 been published : " The Asteroids or Minor Plan- 

 ets between Mars and Jupiter," by Daniel Kirk- 

 wood ; " Movements of the Earth," by J. Nor- 

 man Lockyer ; '' Old and New Astronomy," 

 several parts, by Richard A. Proctor ; " As- 

 tronomy for Amateurs," by Thomas W. Oliver; 

 " The New Astronomy," by Samuel P. Lang- 

 ley. " A Text-book on Astronomy," by Prof. 

 Charles A. Young. The Smithsonian Institu- 

 tion has published a " Bibliography of Astron- 

 omy for the year 1887," by William C. Win- 

 lock, of the U. S. Naval Observatory at Wash- 

 ington, D. C. 



Messrs. Chandler and Ritchie have pub- 

 lished the new " Science Observer Code," to be 

 used in the telegraphic distribution of an- 

 nouncements of discovery and of positions 

 from Oct. 1, 1888. 



ATLANTIC OCEAN, HYDROGRAPHY OF. Rapid 

 progress has been made of late years in the ac- 

 quirement of knowledge concerning the sea and 

 its phenomena. Especially is this true of the 

 great ocean subdivision known as the u North 

 Atlantic." With its dependent gulfs and seas, 

 this ocean covers an area of something like 

 18,000,000 square miles, about one eighth of 

 the total sea-surface of the globe. Commer- 

 cially its importance largely exceeds that of 

 all other oceans. Lying as it does between 

 the great civilized continents, Europe on the 

 east and America on the west, its commerce is 

 as a hundred to one when compared with 

 that of larger and more remote seas. For this 

 reason it has been more thoroughly explored 

 than any other ocean-tract, and its phenomena 

 of tides and currents, winds and temperatures, 

 depths and shallows, are better known. 



The Hydrographic Office of the United States 

 Navy has always been in the front rank of in- 

 vestigation. Struggling from the first with 

 meager appropriations, it has nevertheless con- 

 tributed its full share to the world's knowledge 

 of this great highway of civilization. 



Among the most creditable of its recent un- 

 dertakings is the publication of monthly pilot- 



charts, showing not only the meteorological 

 conditions that may be looked for with reason- 

 able certainty, and the more or less regular 

 variations of currents, but all the obstacles, 

 floating wrecks and the like, of which any 

 trustworthy intelligence can be obtained. To 

 these are added what may be termed the ec- 

 centricities of natural phenomena, such as cy- 

 clones, water-spouts, the appearance of whales, 

 etc. The course taken by all exceptionally 

 severe storms is noted, and, as the charts are of 

 a convenient size (24x30), they can be easily 

 kept for reference in a drawer or in a port- 

 folio, and thus afford a highly valuable record 

 of the sea and its mysteries, for the benefit of 

 navigators. 



A single instance may be cited : The collision 

 between the steamers "Thingvalla" and *'Gei- 

 ser" is among the most startling of recent dis- 

 asters. If the captains of those vessels had fol- 

 lowed, even approximately, the courses plotted 

 for transatlantic steamers on the pilot- chart for 

 August, both vessels might have been still 

 afloat, and the hundred and more persons that 

 went down with the sinking ship might yet 

 have been alive. 



The monthly issue of the pilot-chart is on 

 "Mercator's projection," so called, and in- 

 cludes the whole area between the sixtieth 

 parallel of north latitude and the equator. 

 The preparation of each edition involves three 

 printings, namely, the " base," " the blue data," 

 and the "red data." 



I. The base may be termed the constant of 

 the chart. It is printed with black ink, and 

 includes only the permanent features of sea 

 and shore. Coast-lines, islands, and the like, 

 are clearly marked, also the general set of cur- 

 rents, the compass-card, explanatory tables, 

 storm-cards, etc. The parallels of latitude 

 and longitude divide the whole into squares 

 of ten degrees on a side, and these again are 

 subdivided into what are known as " ocean- 

 squares," of five degrees each. To avoid con- 

 fusion of lines, these smaller squares are not 

 shown, but they are easily plotted by quarter- 

 ing the large parallelograms. 



II. The "blue data." which are printed di- 

 rectly over and upon the permanent data, con- 

 sist mainly of a meteorological forecast for the 

 month following the date of issue. There are 

 also included the principal sailing-routes and 

 steamship-routes recommended for the month. 

 These routes vary from month to month, ac- 

 cording to well-established laws. Thus, in the 

 summer months, the probable southern limit 

 of icebergs is tolerably well known, and the 

 steamer-routes are carried well southward of 

 the danger-line. So in regard to the ordinary 

 sailing-routes, it is probable that any vessel 

 following the sailing directions of the pilot- 

 chart will shorten her voyage by days or 

 hours, according to the length of the trip. 

 These sailing-routes are plotted from the logs 

 and special reports of vessels, which have been 

 accumulating in the Hydrographic Office since 



