THK --SAN: -SUNDAY GALL. ROBBING HURRICANES AND...
1
they - Know \u25a0 tnat - tne storm : win -' not be : a particularly, severe 'one. ja So 1 great is ithe ' merit^didread ' of fa)hurricane •in - somef of ;the ;^West r Indian islands I when^one?has^ approached Wand^u'has passed ;'away/ without < serious I- the ? people", flockI, to the • churches,; sins- ing \Te r, Deums i and ?giving* thanks ; to God: for : theiri escape. VvThepe ' are ] many j hurricanes on whicri < have iwl bed out? thousands ;of; lives- in; a. few.jhours.- besides" destroylngfrowns.l villages ; and •' shipping;: :Not^infrequently,^the*hurri-; canej' generates ,<h uge -..waves • which $ do - tremendousTdamage.vleltiwasUhe'.waye^ fromvjaS hurricane £ which J.. : demolished ; Galveston, ,Texas,v ay few:;> years vX ago, '! spreading : ; havoc • for , miles v along the \u25a0 shore' and; costing; ; 'mariy, : lives. : . : \u25a0 '' •;*\u25a0. ' i'Alnithet.hurrUane In the Bay of Ben- jral^ln|October,; 1865., 1thei water 1 rosa sixteen andY a 'half > feet. - , In : the : Back- ergunge; cyclone,'; on »the i Ganges ; delta. lni;lB76,:.thei water- rose the -land from -ten; toI forty »flve^ feet; drowoina: wer.HOO,ooo.> people.; - ;. .-\u25a0 ;_..•\u25a0. ;-.\u25a0/. iS.iThe^all.'of •: the.; barometer K is;one of the most; lnfallible signs of a hurri- cane. , The fall i is : often both rapid and great, ; 4 and : tho ; ; rapid /and % the greater r; it ' Is ; the >worse v. will \u25a0> be / the storm.* r;.The '^lowest , " , of which I can find* record .was .that ', rioted by^the*: mercurial \u25a0 barometer \of*a : Brit- ish*; ship) in the Bay iot 1 Bengal .a ! few years- agor; when S the s mercury fell so low iln.i In. the glass : that .the scale failed to register; it. The •: last'sreadiric • ob- -\u25a0word that best describes It. . Frightful gales, a heavy sea, sometimes made worse by the cross sea that 13 found Inmany. parts of the stor:n area, and a .wild appearance of the sky all con- tribute to as awful an- experience as the seafaring man is apt to encounter. Through the Hurricanes. I have personally t>een on the out- skirts of three hurricanes and through the center of one. The worst parts. of the three were avoided by maneuvering under the guidance of . the 'laws of storms, and nothing vrorse than fright- ful gales and heavy seas were met. The other, fortunately, was a comparatively mild hurricane, and I encountered -it well north of ? the West indies,^not; far from Cape Hatteras, after Ithad spent most of Its energy. "However, : it was bad enoughl A\ hard gale had been blowing from the southeast for some houra .and during; the * night • It - grew worse. The; ship— 7 a; sailing ship—was under close-reefed topsails, fore storm - staysail and" storm mlzzen. It was/evi- dent that we were right In the storm's' path, but: the proximity of land; and other considerations ; made It Impracti- cable to run out of it. About daybreak the wind suddenly fell ; completely. It became dead calm. .• The general , aspect of the sky: and; sea was; dramatically awful. Over to the southeastward were three huge waterspouts, surmounted by Inky ; black clouds. .In other .directions were turbulent masses; of dark .clouds, with fast : flying "scud" beneath.* s The scene was wild, weird, yet picturesque. Knowing Hhat r we were;, right in the storm center, , theL captain ; called all Jiands on deck;: hatches were battened down ; the ship was :, 4 "scantlllzed.'V that is, every, stitch \ of canvas was taken 1 off her except .the l small pieces : of * topsail \u25a0 left af ter. the yards .were lowered; right down to 'the" lower/caps.; After,] about half. an hour.of waiting for the renewal of the^ blast/ It came; .; The? wind' sud^ denly; came; from !*the" northwest, -ini;a violent squall, and % it?; blew fgqodi; and hard for , about 'three - hours,* but then steadily, moderated.' «The hurricane had passed; u5.,.;,We J (made * sail; set ;'; our course, and soon after made port safely and with-afalr 4 wind. \u25a0*.\u25a0',: ' ; '" It \u25a0is a icurlous fact I that ; electric > dis- plays "; are -almost f always » absent % from a* violent jhurrlcahe.>;. In the --West In- dies, ". when'- the'r signs*' of "an": approach- ing hurricane"" are -^manifested £ and thunder; and^ lightning 'are inoted/>the residents- breathe "a sigh; of ; relief, j for '\u25a0':' ' "\u25a0 \u25a0-">:•\u25a0 .- >\u25a0\u25a0\u25a0:\u25a0: :'>:\u25a0'-\u25a0\u25a0": ..;." :Jr: \u25a0\u25a0>: \u25a0 '.'\u25a0\u25a0\u25a0 : ' on the eastern side of the center they, will, blow from the southward,, and: on the western side from the northward. In the Southern Hemisphere the circu- lation of the winds is just the opposite. As West Indian hurricanes, China ty- phoons and the Indian Ocean storms arc all In the Northern Hemisphere, only Northern Hemisphere conditions will be dealt with here. The laws of storms have become well understood by mariners In" recent years. Every competent navigator can tell with accuracy when a hurricane is threatening him, and he can, if •ho wishes to, avoid the violent winds near the center by maneuvering his ship so to keep her away from the- center. He knows that certain signs foretell a hurricane; he knows froTn the direc- tion and changes of the wind in what direction the center bears from him and In what direction It is moving, and he can tell by the rise or fall of the barometer whether the center is ap- proaching or receding from him. The closer one gets to the center the lower the barometer. r • The first signs of an approaching hurricane are very interesting. The sky is unusually clear; the barometer Is abnormally high; the sunsets are highly colored, or lurid. Next, the barometer begins to fall; light, feath- ery, cirrus clouds appear in the sky, radiating from a point In the sky over the storm center. . The sky then be- comes hazy; halos surround the sun and moon; al ong, low swell sets In on the ocean, coming from the direction of the storm center. The barometer still falls and the wind freshens stead- ily. If the wind remains in the same quarter the observer knows that he Is directly in the path of the storm, which is approaching him. If it shifts, he can ' tell . In what direction the storm is moving relative to his position. If it shifts to the right or to the left he Is able to learn upon, which side of the storm's path he Is, and may maneuver accordingly. As the storm gets closer the sky, from. what is . known among sailors* as a "greasy" sky,. becomes overcast, and a drizzling rain sets', In. \From now, on the various symptoms of . the = hurri- cane become intensified. The, wind gets stronger and stronger; the sky, is cloudy and threatening; ; the 1 barometer steadily." falls. Unless he . has managed to run- out of the storm,, area,: the mariner \ will now; encounter "the ' hurri- cane in ail its ": fury, and fury. i 3the Arthur H. Dutton Late or the Division of Marine Metcor- •o'.ogy, U. S. Hydrograpbic Office. rRO" the data at hand at the time of this writing H would appear that the hurricane which cre- ated such havoc in the Caribbean Sea and in some of the We£t Indies during the latter part of October, while unquestionably a' severe on<\ was by ho means as severe as many others .whioji have occurred in the -same ro- "gion, even in late years. Others winch have occurred in the past have been far more destructive of life and prop- erty. ~i West Indian hurricanes are the most violent tempests known. They are similar to the typhoons of the China Sea and those other ryclones which at times visit the Indian Ocean and the coasts of British India. By some they have been not inaptly termed gigantic \u25a0whirlwinds, covering- a vast area, their Influence being sometimes felt hun- dreds and even thousands of miles 9.way fronj their -renters. These kurricanes belong to that great cla«s of -storms known as "rotary," "circular" or "revolving" storms. They their names from the fact that "the winds they generate blow approx- irrtately in a circular manner about the center. As a matter of fact, however, it has been shown by modern research that the winds do not blow around the tenter in a true circle. They are more like an Jnblowlng spiral. At the re- mote outer parts of the disturbance the wind blows directly toward the .center, the spiral becoming more near- ly- circular as the center is approached. In the center there is a dead calm. This calm center is one of the most peculiar and Interesting features of a hurricane. A shin may b« encounter- ing' the most frightful gales from, say, the southeast, when suddenly th»* wind drops entirely." The air is bo still that a lighted candle may be carried with- out being extinguished. This calm •area varies in diameter, sometimes be- ing but a few miles across, at other as much as ten or twenty miles prross. Then, when It has passed, the wind, suddenly buists forth again with prcat fierceness from another direction. Generally speaking, the closer one gets to the center the more violent the gale. The Hurricane Path. Hurricanes have a motion of trans- lation along a path which Is usually something like a parabola of more or less irregularity. Starting in the trop- ics, well to the eastward usnally, the center moves westward and then with eteadily Increasing "northing" to its course. In time recurving, moving to the northeast and thence finally pass* Ing into higher latitudes. Increasing in area but commonly lessening in force. The typical hurricane track of the North Atlantic Ocean begins ordinarily in the neighborhood of latitude 19 north, longitude 40 west or thereabout. It then moves westward until Itreaches the West Indies, when H recurves and passes off to the northeast, some- times going entirely across the ocean 'und dying out in the neighborhood of the British Isles. The winds of the cyclonic storms in the Northern Hemisphere blow spirally Inward and around, in a direction tgainst the hands of a watch. That Is, talned . shotred but 2C.33 Inches. A frightful gale ensufd. In^the hurri- cane of; Guadeloupe, "West* Indies, in J SG7», the; barometer at Marie Gahante fell from 59. 63 -to 27.95 In one hour and ten* minutes. ' • "LThe study of cyclonic . storms has been closely followed by both' seafar- ing men : and. scientists for over half a century. \ Lieutenant M. F. .Maury of the United States Xavy was one of the* pioneers- In the study and he diil wonders in acquainting seamen with the. nature of these great tempests, lie was' followed by others. . notably by Professox Ferrel of the United States Coa3t, and Geodetic Survey; Meldrum, tho British .authority: Heverendo Padr« Benito Vines, the SpanhCi . hurrkanc authority of Havana, and others of note. The. United States Hydrosraphli Office has for many years been collect- ing data concerning storms from all over the world, and publishes Its pilot charts of the Pacific and the Atlantis oceans, descriptions of notable storms and Instructions as. to. how Jo avoid the centers of such storms as may be encountered. A recent issuo of a hydrographlc of- fice pilot chart contains the following regarding tropical cyclonic storms: The Western Pacific Typhoon. "The typhoon of the western Pacific Ocean is. in .many respects the coun- terpart of the West Indian hurricane of the Atlantic. Both classes of storms have their origin in \u25a0 the' vicinity of tropical groups; of islands and under similar barometrical conditions: both undergo the same slow development and exhibit the: same ter«l» ncy .to' re-. curve upon reaching tho northern limit of the r><-.? theast trades. B9SOI ,•\u25a0 "Atropical cyclonic storm Is due pri- marily to • the ; appearance of a local ai*ea of low -barometer, brought about by the Inequalities In the temperature conditions of the atmosphere. In its Incipient,' stages the deficiency of at- mospheric - pressure . throughout • ©is area may be slight,,amounting to only a few. hundredths ; of an inch. Ac- cording, to varying 1 conditions, such a depress'nnj. either, may -be dissipated or it may deepen and ultimately-de- velop into a well denned storm cen- ter, giving rise to winds of hurricane force. At " the center and during \u25a0 the height of the storm . the barometrio pressure may fall, as ; low as 23.50 Inches.. The space, however, over which this , exceedingly low barometer {pre- vails is generally small, sometimes not more than a few miles in extent. f Around this central low, which con- stitutes, the heart of 'the storm, tha winds circulate In* a direction* contrary 'to the motion 'of the hands of a watch, not s in; circles,'. however, but in spirals, .which continually approach the center,' the; curve described^ by the -.air. 'being similar h in " many'; respects to the fa- mlllar path followed .by, the water. In escaping a from a basin : by," a central \u25a0 openingjn- the bottom.; .To the "north* of the storm center, we thus have easterly ;"and '-. northeasterly .winds ; ; ,to the south; .westerly and \u25a0 southwesterly winds; east: of the center, "southerly and I southeasterly winds "will „prevail; wes^T of the' center, northerly and northwesterly. .The .strength of the wind. diminishes as we go outward,, the winds of typhoons force rarely^ extend 7 Ing,; farther than 300 miles , from. the storm center. Kpß \u25a0"-x I'lt > theT storm center remained sti; tlohary 'a^vesiel 'hove ; to .under storm : canvas V would '§ experience no :"\u25a0>' steady shift -of > the ;> wind, ; but ywould r simply feel the -force of the gale Increase until us full violence was attained, afte which it would gradually blow Itsel out, all from ope quarter. Such, how ever; Is never the case. In addition t the movement of- the air around th storm there is a progresstv movement of the center Itself, carr? Ing with It Us circulating system ? winds. \u0084 "The velocity of the progressive mo- tion of the atorm center varies. With- in the tropics It rarely exceeds tea miles an hour, being her^ much more regular than in higher latitudes, where the velocity ranges from zero, the cen- ter at times appearing to become all but stationary, up to forty miles aa hour. . • "The present theory of tropical cy- clonic storms requires that tnere shall exist at the center, toward which the Incurving surface winds are directed. a rlsing~coltimn of warm, moist air. Upon reaching: the higher levels of the atmosphere the water vapor borne aloft by this air i 3condensed Into clouds, which are carried by the now outward curving rrlnda away from the center on all sides. These c!oud3, then, which are form<?d at a great height and are of the cirrus type, radiating: In long feathery streamers from the region of the ascending column, constitute for the sailor the best indication of the approaching typhoon, sometimes mak- ing their appearance when the storm center ia 1500 miles distant. As the center approaches the der.mty of the cloud canopy deepens until the belt of nimbus, from which torrents of rain descend. i 3 attained. The "width of this belt In front of the center Is, In general, about 150 miles; In the rear it ia less. "A vessel warned by her barometer and by the character of the winds and sea that a typhoon Is approaching should. If sea room permits, seek to avoid It by running. In general terms It may be said that the semicircle of the storm toward the equator 13 the less dangerous, as storm centers In" both hemispheres show a decided tendency to constantly move toward higher alti- tudes. A vessel, therefore, in thi3 semi- circle is free from the danger of again meeting the hurricane after recurving. "Ifthe fait of the barometer and the shifts of the wind are slow it means that the storm Is yet at a distance, and a swift vessel, westward bound in loir latitude, taking advantage of the in- creasing .favorable winds, may manage to outstrip It and thus escape the loss of time incidental to heaving to or seeking the -southern semicircle. A vessel, however, borne to leeward by the temporary surface currents pro- duced by the storm winds, will in gen- eral-be compelled' to cross the storm track. In order to avoid the center. In both of these ; maneuvers the wind should be kept well on the starboard quarter, the effect of this being to carry the vessel constantly from,the storm center. In the vicinity of a ty- phoon the vessel should never run for any length of time with the wind dead aft. "It is. however, only In the outlying portions of the storm that it l.s possible to carry sail. Near the center tha ves- sel must be hove-to under as lltle can- vas as possible, and much depends upon this being done upon the proper tack." • Hurricanes do not occur in the •win- ter time. They 'are most frequent In August. September and October. There have been a few cases on record of hur- ricanes occurring before June, but they are rare. From June until November it behooves the navigator traversing tropical waters to be on his S guard against hurricanes. In the - southern hemisphere, of course, where the sea- sons are reversed, the months, of the »ear in which violent cyclonic storms may be encountered are ths Reverse of those In the northern hemisphere. In conclusion, Itmay be said that the West Indian hurricanes and their, coun- terpart.-the typhoon of the China seas, are the worst storms in the world.' But the 'increase in our knowledge of their nature and the advances in naval archi- tecture and in seanranshlp have les- sened their dangers to a well i found, .well managed .: ship. : A skillful, navi- gator, win avoid them. . or *the .worst parts of .them: a Rood, stanch - ship may. eveji weather. them in safety, pro- vided she ; has enough sea room ia whicij to maneuver. ' THK --SAN: :;FRANGISGO: -SUNDAY 1 GALL. ROBBING HURRICANES AND CYCLONES OF THEIR TERROR
Transcript of THK --SAN: -SUNDAY GALL. ROBBING HURRICANES AND...
they-Know \u25a0 tnat
-tne storm : win -' not
be :a particularly, severe 'one. ja So 1greatisithe
'merit^didread
'of fa)hurricane •in-
somef of;the ;^West rIndianislands Iwhen^one?has^ approached Wand^u'haspassed ;'away/ without <serious I-the ? people", flockI,to the •churches,; sins-ing\Te r,Deums iand ?giving* thanks ; toGod: for:theiri escape. VvThepe 'are ]many j
hurricanes on whicri<have iwlbedout? thousands ;of;lives- in;a. few.jhours.-besides" destroylngfrowns.l villages ;and
•'
shipping;: :Not^infrequently,^the*hurri-;canej' generates ,<h uge -..waves • which $do
-tremendousTdamage.vleltiwasUhe'.waye^fromvjaS hurricane £ which J..:demolished ;
Galveston, ,Texas,v ay few:;>years vXago, '!spreading :;havoc
•for,miles v along the \u25a0
shore' and; costing; ;'mariy,:lives. :.: \u25a0
''•;*\u25a0.
'
i'Alnithet.hurrUane In the Bay of Ben-jral^ln|October,; 1865.,1thei water 1rosasixteen andY a 'half >feet.
-,In:the :Back-
ergunge; cyclone,'; on »the iGanges ;delta.lni;lB76,:.thei water- rose the -landfrom -ten; toIforty»flve^ feet; drowoina:wer.HOO,ooo.> people.;
- ;. .-\u25a0 ;_..•\u25a0. ;-.\u25a0/.iS.iThe^all.'of •:the.; barometer Kis;one ofthe most; lnfallible signs of a hurri-cane. ,The falliis :often both rapid andgreat,;4 and : tho ;;rapid /and % thegreater r;it
'Is;the >worse v.will\u25a0> be / the
storm.*r;.The '^lowest ,",of
whichIcan find*record .was .that ',riotedby^the*:mercurial \u25a0 barometer \of*a :Brit-ish*;ship) in the Bayiot1Bengal .a!fewyears- agor; when S the s mercury fell solow iln.iIn.the glass :that .the scale failedto register; it. The •: last'sreadiric • ob-
-\u25a0word that best describes It..Frightfulgales, a heavy sea, sometimes madeworse by the cross sea that 13 foundInmany. parts of the stor:n area, and a.wild appearance of the sky all con-tribute to as awful an- experience asthe seafaring man is apt to encounter.
Through the Hurricanes.Ihave personally t>een on the out-
skirts of three hurricanes and throughthe center of one. The worst parts. ofthe three were avoided by maneuveringunder the guidance of. the 'laws ofstorms, and nothing vrorse than fright-ful gales and heavy seas were met. Theother, fortunately, was a comparativelymild hurricane, and Iencountered -itwell north of ? the West indies,^not; farfrom Cape Hatteras, after Ithad spentmost of Its energy. "However, :it wasbad enoughl A\ hard gale had beenblowing from the southeast for somehoura .and during; the * night•It-
grewworse. The;ship—7a;sailing ship—wasunder close-reefed topsails, fore storm
-staysail and" storm mlzzen. Itwas/evi-dent that we were right In the storm's'path, but: the proximity of land; andother considerations ;made It Impracti-cable to run out of it. About daybreakthe wind suddenly fell;completely. Itbecame dead calm. .• The general ,aspectof the sky: and; sea was; dramaticallyawful. Over to the southeastward werethree huge waterspouts, surmounted byInky;black clouds. .In other .directionswere turbulent masses; of dark .clouds,with fast :flying "scud" beneath.* s Thescene was wild, weird, yet picturesque.KnowingHhat r we were;, right in thestorm center, ,theL captain ;called allJiands on deck;: hatches were batteneddown;the ship was :,
4"scantlllzed.'V thatis, every, stitch \of canvas was taken 1 offher except .thelsmall pieces :of
*topsail \u25a0
left af ter. the yards .were lowered; rightdown to 'the" lower/caps.; After,]abouthalf. an hour.of waiting for the renewalof the^ blast/ It came; .; The? wind'sud^denly; came; from!*the"northwest, -ini;aviolent squall, and %it?;blew fgqodi; andhard for,about 'three
-hours,* but thensteadily, moderated.' «The hurricane hadpassed; u5.,.;,We J
(made*sail; set ;'; our
course, and soon after made port safelyand with-afalr 4 wind. \u25a0*.\u25a0',: ' ;'"
It \u25a0is a icurlous fact Ithat;electric >dis-plays ";are -almost falways » absent % froma*violent jhurrlcahe.>;. In the --West In-dies, ". when'- the'r signs*' of"an":approach-ing hurricane"" are -^manifested £andthunder; and^ lightning'are inoted/>theresidents- breathe "a sigh;of;relief,jfor'\u25a0':''
"\u25a0 \u25a0-">:•\u25a0 .- >\u25a0\u25a0\u25a0:\u25a0: :'>:\u25a0'-\u25a0\u25a0": ..;.":Jr: \u25a0\u25a0>: \u25a0 '.'\u25a0\u25a0\u25a0 :'
on the eastern side of the center they,will,blow from the southward,, and: onthe western side from the northward.In the Southern Hemisphere the circu-lation of the winds is just the opposite.As West Indian hurricanes, China ty-phoons and the Indian Ocean stormsarc all In the Northern Hemisphere,only Northern Hemisphere conditionswill be dealt with here.
The laws of storms have become wellunderstood by mariners In"recent years.Every competent navigator can tellwith accuracy when a hurricane isthreatening him, and he can, if •howishes to, avoid the violent winds nearthe center by maneuvering his ship soto keep her away from the- center.He knows that certain signs foretell ahurricane; he knows froTn the direc-tion and changes of the wind in whatdirection the center bears from himand In what direction It is moving, andhe can tell by the rise or fall of thebarometer whether the center is ap-proaching or receding from him. Thecloser one gets to the center the lowerthe barometer. r •
The first signs of an approachinghurricane are very interesting. Thesky is unusually clear; the barometerIs abnormally high; the sunsets arehighly colored, or lurid. Next, thebarometer begins to fall; light, feath-ery, cirrus clouds appear in the sky,radiating from a point In the sky overthe storm center. . The sky then be-comes hazy; halos surround the sunand moon; along, low swell sets Inonthe ocean, coming from the directionof the storm center. The barometerstill falls and the wind freshens stead-ily. If the wind remains in the samequarter the observer knows that he Isdirectly in the path of the storm, whichis approaching him. Ifit shifts, hecan
'tell.In what direction the storm
is moving relative to his position. Ifit shifts to the right or to the left heIs able to learn upon, which side of thestorm's path he Is, and may maneuveraccordingly.
As the storm gets closer the sky,from.what is .known among sailors* asa "greasy" sky,.becomes overcast, anda drizzling rain sets', In. \From now,on the various symptoms of.the =hurri-cane become intensified. The, wind getsstronger and stronger; the sky, iscloudy and threatening; ;the 1
barometersteadily." falls. Unless he .has managedto run- out of the storm,, area,: themariner \ will now;encounter "the
'hurri-
cane in ail its ": fury, and fury.i3the
Arthur H. DuttonLate or the Division of Marine Metcor-
•o'.ogy, U.S. Hydrograpbic Office.
rRO"the data at hand at the time
of this writing H would appearthat the hurricane which cre-ated such havoc in the Caribbean
Sea and in some of the We£t Indiesduring the latter part of October, whileunquestionably a' severe on<\ was by
ho means as severe as many others.whiojihave occurred in the -same ro-"gion, even in late years. Others winch
have occurred in the past have beenfar more destructive of life and prop-
erty.~i West Indian hurricanes are the mostviolent tempests known. They aresimilar to the typhoons of the ChinaSea and those other ryclones which attimes visit the Indian Ocean and thecoasts of British India. By some theyhave been not inaptly termed gigantic\u25a0whirlwinds, covering- a vast area, theirInfluence being sometimes felt hun-dreds and even thousands of miles9.way fronj their -renters.
These kurricanes belong to that greatcla«s of -storms known as "rotary,""circular" or "revolving" storms. They
their names from the fact that"the winds they generate blow approx-irrtately in a circular manner about thecenter. As a matter of fact, however,
it has been shown by modern researchthat the winds do not blow around thetenter in a true circle. They are morelike an Jnblowlng spiral. At the re-mote outer parts of the disturbancethe wind blows directly toward the
.center, the spiral becoming more near-ly-circular as the center is approached.In the center there is a dead calm.This calm center is one of the mostpeculiar and Interesting features of ahurricane. A shin may b« encounter-ing' the most frightful gales from, say,the southeast, when suddenly th»* winddrops entirely." The air is bo still thata lighted candle may be carried with-out being extinguished. This calm
•area varies in diameter, sometimes be-ing but a few miles across, at other
as much as ten or twenty milesprross. Then, when It has passed, thewind,suddenly buists forth again withprcat fierceness from another direction.Generally speaking, the closer one getsto the center the more violent the gale.
The Hurricane Path.Hurricanes have a motion of trans-
lation along a path which Is usuallysomething like a parabola of more orless irregularity. Starting in the trop-ics, well to the eastward usnally, thecenter moves westward and then witheteadily Increasing "northing" to itscourse. In time recurving, moving tothe northeast and thence finally pass*Ing into higher latitudes. Increasing inarea but commonly lessening in force.The typical hurricane track of theNorth Atlantic Ocean begins ordinarilyin the neighborhood of latitude 19north, longitude 40 west or thereabout.Itthen moves westward until Itreachesthe West Indies, when H recurves
and passes off to the northeast, some-times going entirely across the ocean
'und dying out in the neighborhood ofthe British Isles.
The winds of the cyclonic storms inthe Northern Hemisphere blow spirallyInward and around, in a directiontgainst the hands of a watch. That Is,
talned . shotred but 2C.33 Inches. Afrightful gale ensufd. In^the hurri-cane of;Guadeloupe, "West* Indies, inJ SG7», the; barometer at Marie Gahantefell from 59. 63 -to 27.95 In one hourand ten* minutes.
' •"LThe study of cyclonic . storms has
been closely followed by both' seafar-ing men:and. scientists for over half acentury. \ Lieutenant M. F. .Maury ofthe United States Xavy was one ofthe* pioneers- In the study and he diilwonders in acquainting seamen withthe. nature of these great tempests, liewas' followed by others. . notably byProfessox Ferrel of the United StatesCoa3t, and Geodetic Survey; Meldrum,tho British .authority: Heverendo Padr«Benito Vines, the SpanhCi .hurrkancauthority of Havana, and others ofnote. The.United States HydrosraphliOffice has for many years been collect-ing data concerning storms from allover the world, and publishes Its pilotcharts of the Pacific and the Atlantisoceans, descriptions of notable stormsand Instructions as. to. how Jo avoidthe centers of such storms as may beencountered.
A recent issuo of a hydrographlc of-fice pilot chart contains the followingregarding tropical cyclonic storms:
The Western Pacific Typhoon."The typhoon of the western Pacific
Ocean is. in .many respects the coun-terpart of the West Indian hurricaneof the Atlantic. Both classes of stormshave their origin in \u25a0 the' vicinity oftropical groups; of islands and undersimilar barometrical conditions: bothundergo the same slow developmentand exhibit the: same ter«l» ncy .to're-.curve upon reaching tho northern limitof the r><-.? theast trades. B9SOI
,•\u25a0 "Atropical cyclonic storm Is due pri-marily to • the ;appearance of a localai*ea of low -barometer, brought aboutby the Inequalities In the temperatureconditions of the atmosphere. In itsIncipient,' stages the deficiency of at-mospheric
-pressure .throughout • ©is
area may be slight,,amounting to onlya few. hundredths ;of an inch. Ac-cording, to varying1 conditions, such adepress'nnj. either, may -be dissipatedor it may deepen and ultimately-de-velop into a well denned storm cen-ter, giving rise to winds of hurricaneforce. At
"the center and during \u25a0 the
height of the storm . the barometriopressure may fall, as ;low as 23.50Inches.. The space, however, over whichthis ,exceedingly low barometer {pre-vails is generally small, sometimes notmore than a few miles in extent.
fAround this central low, which con-stitutes, the heart of 'the storm, thawinds circulate In*a direction* contrary'to the motion 'of the hands of a watch,not sin;circles,'. however, but in spirals,.which continually approach the center,'the; curve described^ by the -.air. 'beingsimilar hin
"many'; respects to the fa-mlllar path followed .by, the water. Inescaping a from a basin :by,"acentral \u25a0 openingjn- the bottom.; .To the"north*of the storm center, we thus haveeasterly ;"and '-.northeasterly .winds;;,tothe south; .westerly and \u25a0 southwesterlywinds; east: of the center, "southerlyandIsoutheasterly winds "will„prevail;wes^T of the' center, northerly andnorthwesterly. .The .strength of thewind.diminishes as we go outward,, thewinds of typhoons force rarely^ extend 7Ing,; farther than 300 miles ,from. thestorm center. Kpß
\u25a0"-x I'lt>theT storm center remained sti;tlohary 'a^vesiel 'hove;to .under storm:canvas Vwould '§experience no :"\u25a0>' steadyshift -of> the ;> wind, ;but ywould r simplyfeel the -force of the gale Increase until
us full violence was attained, aftewhich it would gradually blow Itselout, all from ope quarter. Such, however; Is never the case. In addition tthe movement of- the air around thstorm there is a progresstvmovement of the center Itself, carr?Ing with It Us circulating system ?winds.
\u0084 "The velocity of the progressive mo-tion of the atorm center varies. With-in the tropics It rarely exceeds teamiles an hour, being her^ much moreregular than in higher latitudes, wherethe velocity ranges from zero, the cen-ter at times appearing to become allbut stationary, up to forty miles aahour. .• "The present theory of tropical cy-clonic storms requires that tnere shallexist at the center, toward which theIncurving surface winds are directed.a rlsing~coltimn of warm, moist air.Upon reaching: the higher levels of theatmosphere the water vapor borne aloftby this air i3condensed Into clouds,
which are carried by the now outwardcurving rrlnda away from the centeron all sides. These c!oud3, then, whichare form<?d at a great height and areof the cirrus type, radiating: In longfeathery streamers from the region ofthe ascending column, constitute forthe sailor the best indication of theapproaching typhoon, sometimes mak-ing their appearance when the stormcenter ia 1500 miles distant. As thecenter approaches the der.mty of thecloud canopy deepens until the beltof nimbus, from which torrents of raindescend. i3attained. The "width ofthis belt In front of the center Is, Ingeneral, about 150 miles; In the rear it
ia less."A vessel warned by her barometer
and by the character of the winds andsea that a typhoon Is approachingshould. If sea room permits, seek toavoid It by running. In general termsIt may be said that the semicircle ofthe storm toward the equator 13 the lessdangerous, as storm centers In"bothhemispheres show a decided tendency
to constantly move toward higher alti-tudes. A vessel, therefore, in thi3 semi-circle is free from the danger of againmeeting the hurricane after recurving.
"Ifthe fait of the barometer and theshifts of the wind are slow it meansthat the storm Is yet at a distance, anda swift vessel, westward bound in loirlatitude, taking advantage of the in-creasing .favorable winds, may manage
to outstrip It and thus escape the lossof time incidental to heaving to orseeking the -southern semicircle. Avessel, however, borne to leeward bythe temporary surface currents pro-duced by the storm winds, will in gen-
eral-be compelled' to cross the stormtrack. Inorder to avoid the center. Inboth of these ;maneuvers the windshould be kept well on the starboardquarter, the effect of this being tocarry the vessel constantly from,thestorm center. In the vicinity of a ty-
phoon the vessel should never run forany length of time with the wind deadaft.
"Itis. however, only In the outlyingportions of the storm that itl.s possibleto carry sail. Near the center tha ves-sel must be hove-to under as lltle can-vas as possible, and much depends uponthis being done upon the proper tack."• Hurricanes do not occur in the •win-ter time. They 'are most frequent InAugust. September and October. Therehave been a few cases on record of hur-ricanes occurring before June, but theyare rare. From June untilNovember itbehooves the navigator traversingtropical waters to be on his S guardagainst hurricanes. In the
-southern
hemisphere, of course, where the sea-sons are reversed, the months, of the»ear in which violent cyclonic stormsmay be encountered are ths Reverse ofthose In the northern hemisphere.
In conclusion, Itmay be said that theWest Indian hurricanes and their, coun-terpart.-the typhoon of the China seas,are the worst storms in the world.' Butthe 'increase in our knowledge of theirnature and the advances in naval archi-tecture and in seanranshlp have les-sened their dangers to a wellifound,.well managed .: ship. :A skillful,navi-gator, win avoid them. .or *the .worstparts of .them: a Rood, stanch
- shipmay. eveji weather. them in safety, pro-vided she ;has enough sea room ia whicijto maneuver. '
THK --SAN: :;FRANGISGO: -SUNDAY1 GALL.
ROBBING HURRICANES AND CYCLONESOF THEIRTERROR
![[Osprey] [Warrior Nr. 037] German Seamen 1939-45](https://static.fdocuments.in/doc/165x107/577ccdbc1a28ab9e788c992c/osprey-warrior-nr-037-german-seamen-1939-45.jpg)
