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" "But •' eruptions sometimes come In series. Then, too, - it may be that the two volcanoes which are Btill ' more or less active, Souf riere and V Mont Pelee, work .somewhat as "Mount Vesuvius and Mount Etna have been known to work, the one Inactive while the other emits more or lesa violently. \ "Speaking only from what I have read of the recent eruption in Martinique, and from what we know geologically and his torically of the region, I am of the opin ion that inasmuch as there was , more than. one eruption, it appearing that there was also one on St. Vincent, there will be no Immediate successive eruption.- The tendency . will be to subside, now that some n relief has been afforded the vol cr.nic forces beneath the surface. •*™N EALLY, there is absolutely no f J telling what the volcanoes may r"Y do," said Henry Shaler •Williams. X \ Silliman professor of geology in X Yale University. "They are not well understood by any one, for the laws upon which they operate are' riot well known. There are certain signs by which experts can tell within a compara tively short time what some of them are likely to do;. but in the instance of some other volcanoes they may break forth without any warning , at all. EY PROFESSOR HENRY STTALER WILLIAMS OE YALE. "The modern scientific theory of the emission of lava Is simply that the tre mendous pressure upon the rocks, down a few miles, Is so great that despite the in tense heat they are kept not quite mol ten, almost solid, perhaps. • "When the explosion takes place, reliev ing the 'pressure, It happens oftentimes that the rocks turn from : their solidified state to a melttn condition. Man spoke of "Out In our own Yellowstone] Park the geysers are instances of this steam gen eration. The volcanoes there have not been active for thousands of years, but the earth has not cooled very far down yet, and the steaming water that spouts out and up is in the nature of its action volcanic. In Mexico not very long ago there was one volcano, long inactive, upon which the rocks were still so hot that one could light a cigar by touching the end of it to the. stone. "A volcanic eruption is, on a grand scale, an explosion caused by the gener ation of steam in the great boiler under the surface. I am of the opinion that there were some great crevices in the vicinity of the island of Martinique, through which water either percolated for many years or by the subsiding of the sea a great inrush of water took place. The fact that the sea is said - to have sunk a number of feet there would seem to indicate that there Is a . very great crack or crevice somewhere, and that the water that rushed in was great in volume. That produced a generation of steam* which found vent through the craters of the two volcanoes. VULCANOLOGISTS" of to-day are as much at a loss to define the volcano as were the geologists and astronomers of the days of Dar win. "Vulcanlty" Js as much a stupendous mystery to the Christian students and observers now hurrying to the scene of tho unparalleled disaster at Martinique as was the new coined word of heathen ori gin to the Latin survivors who gazed in awe upon the ruins of Pompeii. Similar were the conditions; similar the ignor ance of the spectator. Among the first and best equipped of epecial students to leave for St. Pierre was Dr. E. O. Hovey, curator of the de partment of geology In the American Museum of Natural History. I found him rushing to make ready for his de parture the next day on the Government relief ship Dixie. There was only time for him to speak in a general way of the previous Investi gations of leading geologists. He was mindful mostly of the large opportunity opening to him for personal observation, but be outlined certain salient results of the studies of such men as Professors Dana, Russell, Judd, Bonney and • Hill, the last named having prepared a mono graph on volcanic conditions In the West Indies. From Dr. Hovey's suggestions and other sources this sketch of the known facts about volcanoes has been carefully compiled. The number of great habitual volcanic vents upon the globe Is estimated at be tween three hundred and three hundred and fifty. There is but one on the whole continent of Europe, Vesuvius, though elsewhere in the Mediterranean there are Bix— Stromboli and Vulcano, in the Li parl Islands; Etna, in Sicily; Grahams Island, a submarine volcano off the Sicilian coast, and Santorlus and Nisyros, In the Aegean Sea. The African conti nent Is known to contain ten active vol canoes, four on the west and six on the east coast, and there are about ten others on neighboring Islands. In Asia, there are twenty-four active volcanoes, but no less than twelve of these are situ ated on the peninsula of Kamchatka. There are no volcanoes in Australia. The American continent contains ¦ m'or« than the countries of the Old World twenty In North America, twenty-five In Central America and thirty-seven In South America. Thus, taken altogether, there are about 117 volcanoes on the great continents and nearly twice as many on the Islands scattered over the several oceans. THE MYSTERY OF "VULCANITY." These volcanoes usually assume in their distribution, a linear arrangement, and nearly all of them have been thrown up along three well-marked bands ' and the branches ; proceeding from them. , The whole eastern coast ) of both the Americas was thought to: be entirely free from volcanoes of anything like recent date, and, just as Professor Judd a few years ago complacently asserted, "as a matter of fact, the actual amount ''of damage to life and property which is af fected by volcanic eruptions is small," so Professor Benney declared that the whole western border of the I Atlantic is destitute of volcanic activity, "were 'Jit not for the long island chain of the Les-; ser Antilles which' separates that' ocean from the Caribbean Sea." R. T. Hill made a special study of conditions in ¦ the Windward Islands. It had been well known that many of the West 'Indian Islands are of limestone, chiefly coraline; that some contain crys talline rocks, while jj others are volcanic. Quite recently it was noted that seven craters still gave signs of life by emit ting steam and that tho curving line of volcanic vents occurred on a. submarine plateau between . the 'deep basin of the Central Atlantic and -that of : the Carib bean Sea. The activity of the Souf riere o~ Bt Vincent was remarked' years ago. the red hot mud that poured down tha mountain. When that matter comes to the cooler air at the surface, especially if there is water with it, it is broken up into fine particles by atmospheric influ ences, and falls for great distances in the form of what people descilbe as ashes. They are not ashes, however, but par ticles of lava. "As to whether there will be sympa thetic action of volcanoes in other parts of the world, I rather doubt that. I think the easement is local, as was the disturb ance, and that there will be no effect at any great distances. The thunder and lightning which accompanied, or followed, the eruption in Martinique were due to the fact that tho tension of the electric forces in the air was disturbed. The disturb ances in the center of the earth being very great and having an upward tendency in relieving, there follow great changes in the configuration of the territories. Great masses of rocks slide and the earth opens. That is an earthquake effect. It is pos sible that those effects are felt at great distances. "Volcanoes are peculiar 1 in their action. We really know but very little about them. Scientists collect all the data pos- , sible and study them carefully, but un fortunately it is not possible to study ; them in action with safety. You know, down at the bottom of the rich Comstock lode, thf^atmosphere is still so hot that it , costs more to cool the air than the gold i is worth when mined, and volcanoes have not been active in our country for a loss time." UNCERTAINTY OF VOLCANOES. Martinique last week and the still greater eruption of Krakatoa, in the Straits of Sunda, southeast of Asia, in 1883. So great was the eruption of Krakatoa that vt filled the atmosphere of the whole world with minute volcanic dust, which for months produced the crimson glow of sunrise and sunset, so noticeable even In this country. At that time a wave was produced in the sea which overwhelmed many cities on the neighboring coast and was recognizable around all the conti nents. ' While the volcanic activity of the Wind ward Islands appears to be dying out. still all these mentioned as having cones are liable to reawakening activity, . but less- so than those at the extreme north ern end of the chain. The tension on the earth's crust having been somewhat re- lleved by the eruptions at Martinique and St. Vincent, early activity would not b« expected. Wherever there are chains of cones, with one occasionally active, there is al ways danger of other cones bursting Into eruption, and most dangerous of all are those peaks which have been quiescent so long that their dangerous character has been forgotten. ;•-*¦' Some of the earthquakes of these isl-. ands arise directly from the volcanic activity of the inner chain. They come from the slipping of the earth's crust, such as that at Charleston, far removed from volcanoes. There is no reason : to suppose, however, that our Atlantic bor der should be permanently free from earthquakes any more than the coast of Carolina. It must not be supposed that the whole of the Windward chain was born o» volcanoes such as we see, in the ele vated peaks of to-day. In fact, the foundations of all are of very great age, although they were carved out by trie atmosphere and the rains from older vol canic materials, but so ancient as not to be the ancestors of the modern cones. Indeed, the southern part of Martinique, greater volcanoes* Many of these are, fre quently in a state of activity. Thus we find Orizaba, a cone rising to a height of about 10,000 feet above the ancient Mexi can plateau, which itself is 8000 feet above the level of the sea. Colima, only a short distance south of Mexico City, is fre quently in eruption. ¦ ¦¦•¦' In Guatemala, Santa Maria, which gave rise to the terrible destruction on April 18, began to be active last November, and is now said to be more active than any volcano known in America since Spanish •occupation. While that is near the Mexi can frontier, Chingo, on the Salvador bor der, is also in a state of general activity. Never So Many Eruptions as Now. Again in Alaska another, volcano is in eruption. . f • So many widespread Eruptions in__the northern continent have never been known in the historic period. ¦'¦ Some twenty-five miles south of Guate mala City is the old site of the city itself, one of the most magnificent spots in the world and having a most delightful cli mate. Nestled in a beautiful valley among the mountains lies the city of Antigua. From one side rises the regular solitary volcanic cone of Agua, while a little fur ther away, on the other side, Is the vol cano of Fuegoand its companion. ¦ Fuego ia said to be always ¦ hot. ¦„, The crater of Agua' was filled with water when in the middle of the sixteenth cen tury it burst 'and overwhelmed the orig inal site by a flood and buried It in vol canic , ashes. The- city was moved three miles farther away. and grew to be one of great magnificence. In 1781 an earthquake leveled it, leaving the ruins: of seventy six churches alone, some of great mag nificence. Then the city ' was moved to its present site, twenty-five miles away over the mountains. • ' - Iceland and the Hawaiian Islands are examples of isolated cones rising out of the* deep oceanic abysses. At' recurring places along the whole Andes there is a successions of great volcanoes, oft general ly greater magnitude than in the north ern hemisphere. ¦ "'.;¦' ¦ • ' While there have .been -many great earthquakes recorded, still - there nave been only two eruptions . vividly before us equal to that of- ancient Vesuvius, and both of these within our memory— that of tween the two continents, such, for in stance, as the small elephant found in Guadeloupe; other animals in Anguilla as large as Virginia deer and the "remains of extinct animals reached even the region of Philadelphia from South America by way of this bridge in the early pleisto cene period. During this period of high elevation the deep canyons were formed upon the sur face, which cut up the continent now forming the Windward Island region into a number of hills and valleys, which, upon the subsequent subsidence, left only the isolated chain of islands which we calif the Windward group; but the sub sidence reduced even these islands to a smaller area than we now find, owins to the subsequent rise in the land, which enlarged their area, but the drowning of the Island land just mentioned, and which occurred in the middle of the pleistocene period, after the early glacial epoch, ex terminated the animals of the islands, which have not since been repopulated, as such could not migrate thither frpm either continent owing to the broad in tervening straits. Represent the Sunken Continent. In a general way, the Windward Isl ands represent the sunken continent. Central America and Mexico illustrate the earth's movements accompanied by vol canic activity of the western region which has been raised into high plateaus while the eastern region had been sink ing. Thus in that region we can see a repetition of the features discovered by the soundings about the Windward Isl ands. These two great lines of volcanic activ ity, situated thousands of miles apart, have no connection with each other what ever, and the coincidence of stupendous activity occurring in the two localities only goes to show that terrestrial move ments are now In progress along both margins of the continents. These move ments are along lines of weakness. In the first place, great heat is developed by the great friction. In the second place, these weak lines facilitate the es cape of the molten matter which may arise, either through a friction of the earth's crust of from the cisterns of lava beneath. While the volcanic . eruptions are more Bv Dr. I. \Y. Spencer, author of "Reconstruction of the An tillean Continent/' "Geological and Physical Development of the Windward Islands, Cuba, Jamaica. Etc./' "The Du ration of the Niagara Falls'' and "History of the Great Lakes." Dr. Spencer, accompanied by Mrs. Spencer, has just reached Washington, aft er a winter spent in ilexico and Guatemala, where the earthquakes and volcanic eruptions, recently reported, occurred, and indeed, one of the hotels where they stayed is among the buildings destroyed. Five years ago they spent the winter hi the" Windward Islands and were at Martinique, being for two days at St. Pierre. The investigations which called Dr. Spencer to Central America included a study of the stupendous changes of level of land and sea in recent geological times and the object in visiting Central America was for the .study of the physical features of that region in comparison with the submarine features of the Wind ward Island::, eo vividly presented to the public at the present moment. *-« ye ANY years ago in my mvesuga /\ /I tions of the origin of our great I Y I lakes ix - vras fo un d tnat lne con " V * I tinent stood at "least 3000 feet JL higher than at the present time during the ages when the great> lakes' valleys were being carved out by the rains, rills and rivers. These investiga tions revealed the occurrence of deep, i iverlike valleys extending seaward across the submerged margin of the continent. Carrying the investigations further south to the coast of Florida and the Bahama Islands and Cuba, it was found that these submerged valleys form the continental rivers, barrancas and canyons, such as are seen at the Grand Canyon of the Colorado, in Arizona, in Mexico and Cen tial America. Such valleys originate In high plateaus of 6000 to 10,000 feet alti tude and extend down to low level plains and the sea. As these valleys extend down to the floor of the Gulf of Mexico and the Carib bean Sea they become evidence that the West Indian Islands once stood as high as these riverlike valleys are now sub merged beneath the sea. Thus the Inves tigation showed that the Windward Isl ands and the Bahamas and, indeed, the whole eastern part of the American con tinent stood once at more than two miles above the present altitude. Herein, as we shall see, lie the causes of the volcanic disturbances resulting In such great dis aster. Gulf of Mexico Brained Into Pacific. At the time North and South America were bridged together by way of the Windward Islands Mexico and Central America were low and the valley of what Is now the Gulf of Mexico was drained into the Pacific Ocean across Mexico by way of the Tehuantepec isthmus, and the valley of the Caribbean Sea discharged Its waters into the Pacific Ocean. Then the Windward Islands formed the back bone of the now submerged continent. While this continent existed long before the historical period, yet from the stand point of the geologist it was very recent, so that In the early glacial period North and South America were connected and stood at an altitude of two miles or more. During the changes of level of laud and sea, which occupied a long period, there were many migrations of animals be- Continuing In this chai^are; St. Vin cent, St. Lucia, Martinique,' Dominica, the mountainous- portions of 'Guadeloupe, Nevis and the island > of 'St. Kitts,'* be yond which the chain" "becomes broken down into the numerous virgin islands rising up out of . a -shallow sea. Fiom Granada, in the Grenadines,- to St. Kitts, there is a repetition of volcanic cones rising to heights { of 4000 or 5000 feet. Eastward of this chain wo 'find Barba does, some sunken banks east of Mar tinique, Grande Terre. or the great'lime stone plains of Guadeloupe, parts. .'of.- Antigua, Barbuda, St. Martin and An guilla. The chain ends in Sombrero, the lonely lighthouse to the West Indies; but again begins in the Bahamas, the re mains of great coastal plains like those along our Atlantic, which escaped the destruction of the West Indian region when it stood at the elevation formerly mentioned. This outward chain is no where volcanic, but it is liable to earth quake action, and throughout these isl ands great damage is periodically pro duced. A Chain of Volcanoes. Returning now to the Windward Isl ands proper, we fira^a '"-double.' chains of islands extending 6rom ; ' i ri(jar, the. coast of South Americ&Vjtp.'Hhe ' St. -.Martin, group, and thence *fcivlrigihg-, around- );ip. Porto Rico, Hay ti: arid Cubd, bn- 'one siae and the Baharhas on, the "other un til they almost join our Southern States. Indeed, they would do so were not the ; old river valleys completely submerged. Ti:e inner chain of these islands begins with the Grenadines, near the coast of South America, a vast number of small islands rising above a submarine plateau now less than 200 feet below the sea. . or less restricted in the area of action and to the distance occupied by the chains of cones, the earth movements are very much more widely felt in the form of earthquakes. Indeed slipping tif even one inch In the rocks at considerable depth may produce a . very. r damaging, earthquake over hundreds- of. ;rnifes?'6f ex-' tent, and the vclean^,^c.tivity: - ;c'(impJir^d with the earthquake^sh^Ks^ggLv*^ •6rilj'\a. very limited evidenefcVof;; the great *eai"tli movements in progress, which are very slow. St;' .Vincent Isle of Calamity. . Tlie;isiand''of St. Vincent is. one of the most ¦beautiful . of the group, but at thu sanie'tlin^ is /one of the most calamitous. Three -?.'or : four" : years ago a hurricane swept'- 6 ver"' it, when every tree is said to have been broken^ off. buildings destroyed and even the-: ¦ insects; swept .from the land,- and howj^e -find another destruc tion scarcely inferior to, that of £> century ago. . • In the island of Martinique we find the northern side of Mont Pelee gently de scending in the form of sloping plains to the sea, with here and there a baby vol cano. On the western side .of , the moun tain the descent is; comparatively steep, and we flniT v a high; elevated terrace just back of tbe town ipf; St/ Pierre, which lay on. a narrow ledge! between the, terrace .arid theVsea. This terrace, however, i* bisected by the valley of the mountain torrent, which made an excellent path way for. the lava and the volcanic mud •which overwhelmed the city. In thesa volcanic eruptions the great danger is not so much from the streams of lava as fiom the streams of mud formed by the condensing steam and hot ashes blown ott the top of the mountain by the explo sions of vapor produced by the infiltration of waters into the molten lava itself. The greater West Indian islands have scarcely any traces of volcanic eruptions except in ancient times. . Whole sheets of igneous matter occur along the eastern sicies of our North and South American mountains, still there are no remains of volcanic cones in Eastern America except a few in the vicinity of Montreal, which is built upon the flanks of an ancient volcano; The changes of level upon the Pacific coast of North and South America have been much more stupendous in later times than those on the eastern side, and conseauentlv we find many more and mpVt' of St. 'Lucia. St; Vincent and ; the ¦;-. foundations of. Dominica belong/; to the 1 aii&ant formation, bu' the volcanic, tones ¦ mentioned had their .¦birth'ri^.lon^. ago g th,aji about ;the beginning /'ejf.-v. the* , : early,-: .¦Brikciftl* period. • -:':>¦ A:-; 3$ /' , : Y ¦ • : : -..V .irSiWe ilif historic' period" sqjne of,. the isl- ,. .atidg : r bate!' -never 1 been?-^n^ activity.. ;;'al- : -. ¦tiibugh.^tfte • cpnes;rand <^m^eTs ,'are . Cp|K& . pl'ete^ncn . as St. ' Kitt^;a^.^eviaj>Mai}>~i;. ;' : -£r^ipU]>%5 )iave^)4eenV,"fe^»^ae*^r^Ath.fci:); ,Hntiuiira3ns- of ' G'ua'tfeloup'4,/butv:T believte 'ncne'-VMs" occurred there since the earlier parfiSeithe' nineteenth century. Dominica ha:ctff£tfght' : eruption ab>u^. lSSti.'Bu-jtf'Mar tiniqui£*U-q.s - supposed. %6' ti$\, quiescent un til itheirr^&ni' indications,)^ f£w months :^in^^^^elghb 9 r; St?,yince|it, erupted : i'n;tfSi2iaBctfdiirkened the, sun far a period ; qi;elgh'ti ; rthree~days,at Baibadoes, a hun-. died rqil$5 away, when the Svh^Je surface' pt : ythat' : .island. was covered '"with the ashes'^Vvv.Y ' ' l-r. ¦ ""'¦¦.'¦.'. './' THE SUNDAY CALL. DANGER SPOTS ON THE EARTH'S CRUST 6