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SIGNAL SERVICE. 



around the earth at a fixed instant of time ; as 

 well as questions of climatology and others 

 bearing upon the prediction of weather-changes 

 far in advance of the time at which these 

 changes happen, or queries as to the character 

 of coming seasons, may be settled." If the 

 Signal Service undertook no other duty, but, 

 discarding prognostications, limited its scope 

 of researches to this international collection of 

 materials for the construction of the sciences 

 of meteorology and climatology, it is not too 

 much to say that the harvest of observational 

 data thus garnered would ultimately be worth 

 all the labor and expense the Service has cost 

 the Government. But, to secure such results, 

 it can not be too widely or urgently insisted 

 on that navigators, ship-owners, steamship 

 companies, and all naval officers should use 

 their earnest efforts and influence to obtain 

 simultaneous weather-reports from all sea-go- 

 ing steamers and sailing vessels. The ablest 

 scientific journal of Great Britain, " Nature," 

 recently said that it " earnestly hopes that the 

 navies and the mercantile vessels of all nations 

 will soon join, in carrying out this magnificent 

 scheme of observations, originated by the Amer- 

 icans in 1873, and since then further developed 

 and carried on by them with the greatest abil- 

 ity and success." ' Sentiments similar in effect 

 were expressed at the International Meteoro- 

 logical Congress convened in Rome, Italy, in 

 April, 1879. 



The Coast Signal Service is another impor- 

 tant arm of the organization. By act of Con- 

 gress, the Secretary of War was authorized to 

 establish signal stations at the lighthouses and 

 life-saving stations on the lakes and seacoasts, 

 and to connect these signal stations with tele- 

 graph-lines, to be constructed, maintained, and 

 worked under the direction of the Chief Sig- 

 nal Officer of the Army ; and the use made ot 

 the life-saving stations is subject to such reg- 

 ulations as are fixed upon by the Chief Signal 

 Officer, the Secretary of War, and the Sec- 

 retary of the Treasury. By this cooperative 

 arrangement, the Signal Service has become a 

 valuable if not an indispensable auxiliary to 

 the sister services with which it connects, and 

 shares very materially in the labors and re- 

 sponsibilities especially of the Life-Saving Ser- 

 vice. 



The coast signal stations aim to warn vessels 

 within signaling distance of the approach of 

 storms, and to give the life-saving stations 

 quick notice of marine disasters calling for 

 rescue, as also to furnish any intelligence to 

 the latter, or to the lighthouses, which may 

 insure their more efficient working. Connect- 

 ed by wire or submarine cable, as all the signal 

 stations on the coast are, from Sandy Hook, 

 N. J., to Stnithville, N. C., and connected simi- 

 larly with the office of the Chief Signal Officer 

 at Washington, whence they are kept advised 

 of any change in the meteorological status, they 

 are thus enabled, from their full ocean view, 

 to communicate directly any warnings from 



the Chief Signal Officer to passing ships, or to 

 convey to him any facts which may be of use 

 to the Washington office. The telegraphic 

 wires connect each station with the War De- 

 partment. The weather reports and observa- 

 tions on the indications of the sea thus ob- 

 tained are often of the greatest value to the 

 Washington office in its work of preannouncing 

 the force, direction, and velocity of the great 

 hurricanes from the West Indies, which im- 

 pinge upon our Atlantic seaboard and sweep 

 the sail-whitened waters on the eastern side of 

 the United States. 



As an illustration of this, it may suffice to 

 note the ocean conditions which the Coast Sig- 

 nal Service telegraphs to the Chief Signal Of- 

 fice thrice daily, and oftener if need be. It 

 has long been known by meteorologists that 

 marine cyclones foreannounce their movements 

 by a storm-wave formed in the central part of 

 the barometric depression, where, the attenua- 

 tion of the atmosphere being much greater than 

 on the outer circles, the circumferential pres- 

 sure serves to head up the water of the sea. 

 " When living on the Bermuda Islands," says 

 General Reid, the eminent investigator of 

 storm-phenomena, " I was frequently interest- 

 ed by observing the change of direction in the 

 surf beating against their shores. A coming 

 storm would roll its undulations so as to break 

 upon the south and southwest side of these At- 

 lantic islands ; and, as gales proceeded north- 

 ward, the sea was seen breaking on their north- 

 ern reefs." The " cyclone-rollers," as Pidding- 

 ton observed, may be "felt at a great distance 

 from storms" ; and, as he shows, even a ship 

 far out at sea, if her commander will carefully 

 note the swell of the ocean, may be forewarned 

 of an approaching gale. Both of these inves- 

 tigators give abundant evidence that the pecu- 

 liar ocean-swell "is often felt at 10 or 15 

 (600 to 900 miles) of distance" from the tem- 

 pest. In the summer of 1873, when the great 

 August hurricane which so furiously assailed 

 and wrecked several hundred sail, was still 

 passing over the Bermudas, its long dead swell 

 was outrunning its center by 600 miles, driv- 

 ing in the bathers at Long Branch and pour- 

 ing into New York Bay. The steamer Albe- 

 marie encountered its forerunning wave on hei 

 voyage from Halifax to the Bermudas; and, 

 though the morning was fair, suspecting dan- 

 ger, the vessel was hove to for a few hours to 

 examine the swell. Concluding that the hur- 

 ricane was advancing directly upon him, her 

 captain changed his course from southerly to 

 westerly, and by a slight detour eluded the 

 gale. As one by one, yet all independently, 

 the coast signal observers on any day telegraph 

 to the central office the same significant tid- 

 ings of the ocean-indications of an Atlantic 

 gale the intensity and direction of the swell 

 their concurrent observations often present un- 

 mistakable proofs of the presence, course, and 

 progressive rate of these menacing meteors. 

 The intelligence thus afforded is indispen- 



