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 AMERICAN NATURALIST. 
 
 Vol. xiv. — NO VEMBER, 1880. — No. 11. 
 
 D 
 
 THE ISLAND OF DOMINICA. 
 
 BY F. M. ENDLICH. 
 
 OMINICA has always been veiled in a halo of mystery. 
 Vague rumors of " smoking mountains," of springs flow- 
 ing " liquid sulphur," and of caverns of prodigious dimensions 
 have invested it with more than ordinary interest. 
 
 The island was discovered by Columbus on his second west- 
 ward voyage in 1493. It belongs to the " Windward Group," 
 the whole of which form a portion of a circle directly east of the 
 Caribbean sea. Geographically Dominica is located about at N. 
 lat. 1 5 , and 6i° long. W. of Greenwich, and its climate, conse- 
 quently, is subtropical. Without entering into details, which 
 here would carry us beyond our limits, it may be said that the 
 entire Windward Group belongs to one geological system. Gen- 
 erally speaking we may regard these islands— excepting Antigua, 
 Barbadoes and Trinidad— as the highest remaining portions of 
 an extensive eruption, the age of which falls near or into the 
 Eocene period. From their orographic character, as well as from 
 their relative position, the temptation is great to consider them 
 the projecting points of the eastern side of one huge, serrated 
 crater-rim. Detailed observations are too meagre as yet, how- 
 ever, to attempt the establishment of any such hypothesis. 
 Lithologically speaking the erupted material shown on Dominica 
 strikingly resembles that of the southern Wasatch range. Even 
 in special arrangement of the trachytic series the analogy is 
 remarkable. It is furthermore borne out, on this and other 
 islands, by the general contours of elevations, and by the simi- 
 larity of the effects produced by extensive erosion. 
 
 Rising abruptly from the sea, the shores of Dominica afford 
 
 VOL. XIV. — NO. XI. 
 
762 The Island of Dominica. [November, 
 
 comparatively few landing places, and unless a shelving beach 
 can be found, the boat may not unfrequently be swamped in an 
 attempt at landing. Owing to the character of the rocks com- 
 posing the body of the island, erosive action has been productive 
 of varied results. The immediate base is composed of hard, com- 
 pact sanidine-trachyte ; overlying occurs a series of easily decom- 
 posing conglomerates, while the higher portions are again formed 
 by trachyte. In giving these facts, it may be stated that the 
 southern end of the island is spoken of. Towards the high inte- 
 rior and north, but few explorations have been accomplished. 
 Wherever the more easily yielding conglomerates have been 
 attacked by erosive agents, almost vertical walls and narrow 
 gorges are found. Steep slopes are not wanting in the trachytes 
 proper, but they seem to be owing less, perhaps, to erosion than 
 to be the expression of original contour. 
 
 Towards the interior the highest mountain reaches an absolute 
 elevation of 5500 feet; within a very few miles of shore, how- 
 ever, 3000 to 3500 feet are attained by a number of peaks. 
 It would be difficult to imagine any more beautiful spot than the 
 southern end of Dominica. Combined with outlines which 
 resemble the rigid stability of Alpine scenery is the luxuriant, 
 sub-tropical flora. An abundance of moisture, equable tempera- 
 ture and absence of the destructive hand of civilization allow 
 full scope for the development of plant life, and have preserved 
 for our admiration a region which cannot fail to call forth enthu- 
 siasm. Few sights can be more charming than that of a high, 
 vertical wall clothed throughout with abundant vegetation, exhib- 
 iting numerous shades of vivid green. The Roseau river is the 
 most important watercourse of the island. It heads in the higher 
 mountains, flows in a westerly direction, forms a fine waterfall 
 near Laudat, and enters the sea on the leeward side of Dominica 
 at the main port, the town of Roseau. 
 
 From the earliest days, since its discovery, Dominica has been 
 a bone of contention between England and France. Ample forti- 
 fications, now allowed to decay, speak of the importance which 
 each nation attached to its possession. By the treaty of Fon- 
 tainebleau it was ceded to Great Britain, but in 1802 wns again 
 recovered by France. Finally, in 18 14, the former power once 
 more added it to her list of colonies, and has retained it since 
 that time. At the time of its discovery, and for many years after, 
 
1 8 8 o . ] The Island of Dominica. 763 
 
 Dominica was one of the favorite resorts of the Caribs. This 
 warlike nation here found mountains and water, fish in plenty and 
 fruits in the valleys. From their strongholds in wild fastnesses 
 they more than once issued upon aggressive warfare and severely 
 harassed the settlers of neighboring islands. In the course of 
 years, however, the Caribs have become greatly reduced in num- 
 bers, until to-day there is but a mere handful remaining. It is 
 certainly a subject for serious reflection to note the almost com- 
 plete extermination of a once powerful people by the advance of 
 civilized measures and by superior instruments of aggressive 
 warfare. In view of our own vexed Indian question we may fee* 
 inclined to allow personal or national interests to warp judgment 
 or to subvert justice. When, however, the same spectacle is seen 
 from the standpoint of an unimpassioned observer, it assumes a 
 totally different aspect. Dominica and Trinidad are said to con- 
 tain the last surviving Caribs. On the former island perhaps one 
 thousand may still be living, on the latter not so large a number. 
 Secluded in the mountains of the interior, they are but rarely 
 seen at the settlements. Chivalrous as they formerly were, they 
 have retained to some extent their tribal characteristics of vener- 
 ation for hereditary and accidental authority and good treatment 
 of their women. These latter have been accustomed to wait 
 upon the " lords of creation " most assiduously, and are rewarded 
 by respect and far more consideration than is usually found 
 among savages. In spite of former cannibalism the Caribs have 
 often shown traits of greatness and magnanimity. At present 
 they occupy a reservation set apart by the government. Peace- 
 ably passing their time, they devote their energies to the manu- 
 facture of exceedingly tasteful baskets. Double plaiting renders 
 the latter waterproof, and the careful work bestowed upon them 
 is recognized by the numerous uses to which they are put. 
 
 In physical appearance these people closely resemble the 
 nobler tribes of our North American Indians; long, straight, black 
 hair falls down over their shoulders ; the cheekbones are prom- 
 inent, nose flattened somewhat, mouth broad and chin massive. 
 Much lighter than the negro population, the color of their skin 
 is yellow to brown. The influence of intermarriage between 
 negro and Carib is plainly perceptible in their descendants. A 
 decided lightening of color, an improvement in features and 
 stature as well as decreased curliness of the hair, denote the pres- 
 
764 The Island cf Dominica. [November, 
 
 ence of blood which for many years controlled the Windward 
 islands. Many of the girls belonging to this class, who may be 
 found some distance away from the coast, are really quite pre- 
 possessing in appearance. 
 
 A total population of about 26,000, of which Roseau claims 
 3000, is ascribed to the island. As might be expected, the con- 
 stant change of ruling power has had a detrimental effect upon 
 the language spoken by the present population. Defying alike 
 the Parisian and the Englishman, a French patois, is used as the 
 means of lingual communication. Indolence in properly framing 
 words on the part of the negro inhabitants, and perhaps an admix- 
 ture of some Carib phrases or intonations have rendered it difficult 
 for any one but a resident to understand what is spoken. Very few 
 Caucasians are living on Dominica, as the mountainous character 
 of the colony forbids extensive enterprises. Coffee was intro- 
 duced, during the last century, from Martinique, and was formerly 
 largely cultivated. Recently, however, an insect has attacked the 
 delicate leaf and destroyed the plants. Experimentally the 
 Liberian coffee-plant has been introduced, and it is hoped that its 
 thick, hardy leaf may successfully withstand the ravages to which 
 the other has succumbed. Limes are raised in great quantities, 
 and have become so thoroughly acclimated that they flourish 
 without requiring any particular attention. Citric acid is manu- 
 factured from them and exported. One of the staples is sugar, 
 but the annual production does not exceed a few thousand tons. 
 
 From the appearance of the town of Roseau, some inferences 
 may be drawn as to the struggles which were made for possession 
 of the island in times gone by. A dyke, capable of being forti- 
 fied, protects the water front, while forts, located on the " Mornes" 
 near the town, were destined to keep at bay the invading foe. 
 True, to-day, all of the elaborate defences would speedily fall 
 before the heavy armament of a man-of-war, but at the period of 
 their usefulness they were sufficiently formidable. As the inhabi- 
 tants are mainly negroes, the town does not present an imposing 
 array of fine structures. Small, wooden huts, thatched in part, 
 protect th£ir families from rain and storms. Illustrating the good 
 taste shown on all these islands, there is a " Public Garden" near 
 the town ; fountains cool the air, and conveniently placed seats 
 invite the seeker after shade and the admirer of scenic beauty. 
 
 During our stay on the island (February, 1880), we had occa- 
 
PLATE III. 
 
 Esequibo Indians. 
 
\ 
 
 Digitized by the Internet Archive 
 in 2011 with funding from 
 The Library of Congress 
 
 http://www.archive.org/details/islandofdominicaOOendl 
 
i88o.] The Island of Dominica. 765 
 
 sion to visit several points of interest, thanks to the courtesy of 
 gentlemen living there, and the kind offices of Dr. Brown, of 
 Princeton. Prominent among the "mysteries" of Dominica, the 
 " Boiling lake " and the " Soufreurs " have always held their 
 place. The latter are located near the extreme southern end of 
 the island. Leaving Roseau early in the morning, we were 
 pulled along the coast for six miles by four strong oars. On 
 account of the difficulty in landing at some localities, the boats 
 are without rudders. Their place is supplied by a steersman who 
 ably directs the course by means of a short paddle. Boats used 
 by the negroes are built in the shape of canoes, and are partly 
 sharp-keeled dug-outs, the sides being boarded to increase the 
 depth. After we had landed, a very warm climb brought us to 
 the first appearance of chemical changes in the rocks. The feld- 
 spathic constituents of the trachyte were thoroughly decomposed, 
 the ground white and dusty with but little vegetation. Some 
 search revealed a number of cavities in the altered material, which 
 were lined or filled with beautiful crystals of sulphur. Although 
 the surface of this decomposed area showed a normal tempera- 
 ture, this increased so rapidly with depth, that at little more than 
 a foot it was unbearable to the touch. Small streams in the 
 vicinity were found to measure 45 ° C, and the water evidently 
 carried ferric sulphate and alum in solution. Ascending higher, 
 through tall weeds, and plucking guavas on the way, we observed 
 a narrow gully in a rocky mountain side, whence steam was 
 issuing in dense volume. It was a matter of some difficulty to 
 cross a ravine which separated us from this point of greatest 
 chemical activity. Here our colored guides deserted us. Not 
 that their guidance was in the least valuable, but we wanted them 
 to carry specimens. No persuasion, no threat could induce them 
 to follow us to the place where, in their opinion, evil spirits 
 resided. " They will throw rocks at you," was their only reply, 
 accompanied by an obstinate negative shake of the head. Who 
 " they " were could not clearly be made out. A prevalent popu- 
 lar superstition regarding evil-minded "mountain spirits," fur- 
 nished us a clew, however, as to the identity of undefinable 
 enemies. Once within the active region of the Soufreurs it be- 
 came necessary to be cautious in our movements. The ground 
 was treacherous and of about 6o° C. temperature. Small open- 
 ings lined with crystals of sulphur, steadily emitted sulphurous 
 
y66 The Island of Dominica. [November 
 
 gases. At some places it became difficult to breathe, so dense 
 was the volume. After passing over about quarter of a square mile, 
 densely studded with fumaroles, we entered the gorge seen from 
 a distance. Steep, slippery slopes of partly decomposed trachytes 
 here enclosed a narrow stream of water which was' found to be 
 heated nearly to the boiling point. Sulphuretted hydrogen was 
 present in great quantities, and hot steam-jets attacked us from 
 the most unexpected quarters. Along the rock-walls we found a 
 number of openings, sometimes nearly half a foot in diameter, 
 from which either steam or gas issued. 
 
 " And it bubbles and seethes, and it hisses and roars, 
 As when fire is with water commix'd and contending," 
 
 truly describes what we encountered while slowly climbing 
 upward in the gully. From the bottom, through narrow crevices, 
 by way of cylindrical openings, all around us, steam and gas 
 threatened to bar farther progress. In the bed of the hot creek 
 the water presented an appearance of violent boiling, owing to the 
 rapid emission of large quantities of gas. So thick was the steam 
 at this point that it began to interfere with respiration, and at 
 times our surroundings were entirely shut out from view for 
 several minutes. A large percentage of mineral constituents in 
 the water rendered it totally unfit to drink, even when cooled. 
 Ascending farther in the gorge, escape from which was negatived 
 by barren walls on either side, we finally reached an elevation of 
 about 1 200 feet above sea level. Here we found the water cold 
 again, trickling in small streamlets over the rocks. We had 
 escaped from the region of gas and steam and had passed, at the 
 same time, the upper limit of present chemical action. Complete 
 metamorphosis, produced by long-continued decomposition, had 
 placed these rocks beyond the influence of atmospheric agents. 
 Burned out, not now taking part in the phenomena of the imme- 
 diate vicinity, they remain as mute witnesses of the forces which 
 there must have been at work for ages. 
 
 To our satisfaction we were enabled to find in some fragments 
 of fresh and partly decomposed trachyte, the solution of the 
 striking scenes witnessed. Minute crystals or irregular fragments 
 of pyrite impregnate the rock throughout a definite zone. In 
 weight the quantity of this pyrite may amount to about twenty 
 per cent. Moisture in conjunction with atmospheric air will 
 readily decompose this mineral, a process which is accompanied 
 
 
i88o.] The Island of Dominica. y6j 
 
 by generation of heat. Such action will be facilitated and accel- 
 erated by the extremely small size of the individual pyritic parti- 
 cles. The postulated reagents are abundantly supplied at the 
 locality in question. In addition to the ferric compound the 
 feldspathic portions of the trachyte are attacked, yield to altering 
 agents, and by increase of volume accompanying chemical 
 change, add their share to the generation of heat. At the same 
 time the decomposing mass is physically disintegrated and then 
 easily removed by natural causes, thus permitting a repetition of 
 the same process, until the supply of unstable chemical com- 
 pounds may become exhausted. Irregularities of either chemical 
 or physical character within trachytic rocks are by no means of 
 rare occurrence. Should their nature be such as to yield more 
 readily to active reagents than the portions surrounding them, 
 decomposition will progress at a higher rate of speed along cer- 
 tain lines or in certain directions. Thus vents may be formed 
 which besides serving as outlets for gases and liquids, will allow 
 fresh supplies of moisture and air to reach points as yet com- 
 paratively intact. 
 
 Returning to our darkies we found them unfeignedly surprised 
 to see us still alive, but they evidently concluded that we were 
 reserved for some fate even worse than " having rocks thrown 
 at us." 
 
 " Wotten Waven " is another point deserving of special study. 
 A morning ride along the left bank of the Roseau, which led 
 through flourishing lime plantations, brought us to the undisturbed 
 timbered slopes of a subtropical zone. Huge tree ferns over- 
 shadowed the narrow path cut into a steep face of trachytic con- 
 glomerate, over which we were gradually winding our way 
 upward. It would be impossible to furnish a pen picture capa- 
 ble of giving even a faint idea of the beauty inherent in such a 
 forest. The cool moist atmosphere is refreshing, and every step 
 taken forces admiration from those whose eyes are accustomed to 
 the more sombre grandeur of northern climes. A column of 
 steam slowly wreathing skyward betrayed the presence of Wot- 
 ten Waven. These " thermal springs " lie about 1600 feet above 
 sea level, but not within pyritiferous trachyte. A short distance 
 from the timber edge we found a creek flowing cold water. Fol- 
 lowing this down, the first hot springs were soon encountered. 
 Here the water issued from small apertures in trachytic rock 
 
768 The Island of Dominica. [November, 
 
 which showed but little decomposition on the surface. Varying 
 temperature, ranging from 85 C. to boiling point, was observed, 
 while the water of the creek measured 68° C. But a few yards 
 to the right, a narrow gully ran off from the creek, ending 
 abruptly in a vertical wall, the lower portions of which were com- 
 posed of trachyte. In the latter an aimost circular opening, about 
 two feet in diameter, led to regions unknown. Standing in front of 
 this opening a regular pulsation within was observed. So far as 
 could be seen, it was the mouth of a somewhat extended cavity 
 into which water rushed simultaneously, at nearly regular inter- 
 vals, from the two sides parallel with the trend of the ravine. If a 
 comparison be attempted, the total effect might be likened to the 
 noise produced by a ship's engine, accompanied by a similar 
 though slighter tremor. Four pulsations occurred on an average 
 during every seven seconds, and the fifth ejected a large mass of 
 water through the opening. This main "spring" of Wotten Waven 
 must therefore be regarded as a geyser. On account of the slip- 
 pery character of the rocks and the imminent risk of being 
 scalded, the temperature could not be obtained at the moment of 
 emission. As the water flowed off it measured 98 C. Besides 
 this large geyser, numerous small ones occur here, all, however, 
 sending their water in lateral directions, not vertically. In addition 
 to the rock openings ejecting water, there were many from which 
 steam issued. Sometimes this was not visible at the immediate 
 mouth and it became a matter of discrimination as to the selec- 
 tion of standing places. Taking the temperature of several of 
 these jets, we found a maximum of 102 C Noticeable is the 
 total absence of sulphuretted hydrogen. While at the Soufreurs 
 all the silver we carried with us almost instantly turned black, 
 we could here find no point where bright coins would be at all 
 affected. 
 
 Although in a general way the sources of heat are due to the 
 same causes at Wotten Waven as at the Soufreurs, some differ- 
 ences were found. Decomposition is the main factor, but in this 
 instance pyrite is not the material most violently affected. Small 
 quantities of the mineral certainly occur, and it is quite possible 
 that its presence in larger proportion may originally have initiated 
 the process of chemical changes. At this locality the trachytes 
 contain a large percentage of soda feldspar (oligoclase). This is 
 rapidly decomposing, and by the chemical reaction itself, as well 
 
jggo.] The Island of Dominica. 7 6 9 
 
 as by the considerable increase in volume incident thereto, heat is 
 produced. In several instances, where the same changes were 
 going on in rocks containing oligoclase, we have found thermal 
 springs in the immediate vicinity. While decomposition of 
 pyrite is more rapid, it does not extend so far from the surface 
 into the rocks as that of the feldspar. In connection herewith it 
 may be mentioned that the waters of Wotten Waven hold an 
 exceptionally large amount of alumina in solution. In spite of 
 the diminutive size of the majority of the geysers, the quantity 
 of water delivered is considerable. As it nearly all flows off, a 
 very large supply must be furnished by percolation, or by entrance 
 through fissures and along subterranean watercourses. 
 
 On January 4, 1880, the inhabitants of Roseau had cause to 
 feel somewhat alarmed. Taking into consideration the myste- 
 rious legends as to volcanic activity on the island, it will readily 
 be understood that the appearance of a huge, dark cloud over the 
 town shortly before noon of a clear day, might awaken some 
 apprehensions. More so, however, when that cloud began to " rain 
 down" fine particles of gray, mineral-like material which soon 
 changed the green foliage of all vegetation to its own color. 
 Pompeii and Herculaneum saw the initiation of their destruction 
 in a similar cloud. So far as could be determined by cool obser- 
 vers, among whom Dr. Nichols of Roseau was prominent, the 
 cloud extended for a distance of about eight miles beyond the 
 town and then was lost, going seaward. Even in the latter part 
 of February the finely divided " ash " could be found on many- 
 plants. It consisted of very minute fragments of trachytic rock 
 and small crystals and particles of pyrite. The general impres- 
 sion was that a volcanic eruption had taken place at " Boiling 
 Lake." 
 
 Neither definite detonations were heard nor seismic disturb- 
 ances felt by the more critical observers. A low rumbling noise 
 seems to have preceded the appearance of the cloud. Several 
 venturesome explorers determined to investigate matters, but 
 were obliged to return without results, as all access to the lake 
 had been barred by dislodged rocks and earth. During our stay 
 at Roseau a party was organized to visit the lake, and a new road 
 was cut through the forest. Numerous colored attendants, whose 
 climbing qualities and endurance we could not but admire, trans- 
 ported baggage and provisions. Reaching a point several miles 
 
jjo The Island of Dominica. [November, 
 
 beyond Laudat, we were obliged to relinquish our riding animals 
 and proceed on foot. Wet and slippery the newly cut path fol- 
 lowed the sharp crest of a narrow ridge until it reached an abso- 
 lute elevation of 3200 feet. From here the view was overpower- 
 ing. Before us lay miles of mountain slopes, utterly denuded of 
 vegetation. Dull gray was the color of the entire surface, and 
 the broken stumps of once gigantic trees spoke eloquently of the 
 terrific force which had laid in desolate waste what but two months 
 before had been a dense primeval forest. Behind us was the 
 beautiful valley of the Roseau, the wooded mountains skirting it 
 and withal an expression of serene repose. To our right steam 
 was fitfully issuing from a crater-like depression, to the left rose a 
 majestic column of white steam from Boiling lake. 
 
 We descended a very steep slope and found the " erupted " 
 material to consist of broken and disintegrated fragments of 
 trachyte thoroughly impregnated with pyrite. In other words, 
 we had before us fresh rocks which were analogous to those we 
 found decomposed at the Soufreur and identical with the " ash " 
 which had fallen at Roseau. By far the greater portion of the 
 mass was reduced in size so as to pass through a twenty-mesh 
 sieve. Boulders weighing several hundred pounds were not 
 wanting, however. Arrived at the rivulet at the end of the 
 mountain slope, we found the water to be warm. With the lim- 
 ited amount of time at our command, it was impossible for us to 
 visit the right-hand depression, so we turned our steps towards 
 the lake. The former was the scene of greatest activity, and the 
 place from which the dislodged rock material had issued. Re- 
 cent disturbances had rendered access so precarious, however, 
 that it would have been necessary to spend more time than we 
 could afford in effecting an entrance to the bottom of the " crater." 
 An inky black creek was crossed shortly, and but a few yards 
 beyond it one of milky whiteness running parallel. Both were 
 warm, about 6o° C. Probably the presence of iron sulphides 
 accounts for the color of the former, while the latter, judging 
 from its taste, contained mainly alkalies. As a noticeable fact, 
 we observed that these colors were not merely due to the effect 
 of underlying rocks, but that the water was really so colored. 
 Over rocks, through water, knee deep in yielding mud we scram- 
 bled along, until we finally stood at the edge of an oval basin 
 surrounded by almost vertical walls, where the Boiling lake had 
 been. Formerly it must have extended about three hundred by 
 
l38o.] The Island of Dominica. y 7l 
 
 two hundred and fifty yards, but at the time of our visit the dis- 
 turbances about one and a-half miles distant had destroyed the 
 lake, leaving only a boiling spring of about fifteen by twelve feet. 
 Here the water issued with tremendous ebullition. It was unsafe 
 to approach within a few feet of the spring after the descent to 
 the former lake bottom had been made, and it thus became im- 
 possible to ascertain the exact temperature. The spring was 
 located near the center of the lake bed, from where its ^water 
 flowed off through a narrow opening in the enclosing walls. 
 Every step was taken on hot ground, and a cane pressed down 
 into the earth would be followed by the hissing sound of escaping 
 steam upon withdrawal. Fortunately we found cold water, at the 
 upper end of the lake, trickling down on the face of a rock, and 
 we were spared the torture of 
 
 " Water, water everywhere 
 Nor any drop to drink." 
 
 From examinations made we found that the lake had not been 
 filled up by masses of rock or soil projected into it, but that the 
 confining dam had broken away and the water had flowed off. In 
 view of the fact that seismic action appears to have been very 
 subordinate at the time of the " eruption," it seems probable that 
 the lake suddenly received accessions of water and thus forced 
 its way downward, carrying with it the former barrier. At best 
 the depth of water, unless perhaps immediately over the hot 
 spring, which once formed an integral portion of the lake, must 
 have been inconsiderable. Its elevation is about 2400 feet above 
 sea level. 
 
 Had not personal inspection of the surroundings of the lake 
 been convincing that the " eruption " did not take place there, the 
 evidence afforded by mutilated plants would have been conclu- 
 sive. No other word but " terrific " can express the conception 
 of the mass and overwhelming force with which rocks and 
 boulders were hurled into the forest On the southerly side— 
 towards the above-mentioned crater-like depression— the bare 
 broken trunks and stumps of trees, rarely over fifteen feet high' 
 were literally mashed, while comparatively untouched on the 
 reverse. About one-sixth to one-tenth of the total diameter was 
 worn away by repeated concussion, and trees of tough fiber, so 
 much as remained of them, were absolutely torn to shreds. No- 
 where did we find indications of heat which might have been 
 sufficiently great to fuse any of the minerals contained in the 
 
JJ2 . The Island of Dominica. [November, 
 
 trachyte. The reduction of the latter in size was purely mechani- 
 cal, largely due to attrition, although certainly the force producing 
 it was owing to causes entirely different. We estimated the area 
 thus razed, of timber, at about nine square miles, and the average 
 thickness of deposited lithological material at eighteen inches. 
 Allowing for the fact that the latter was not densely packed, this 
 estimate furnishes a total amount of more than 27,000,000 tons 
 which had been removed from their normal position by catastro- 
 phic action. 
 
 As to the causes which produced the " eruption," the evidence 
 on hand is sufficient to arrive at some conclusions. First of all, 
 the idea of volcanic eruption must be dismissed. No grounds for 
 such assumption can be found, and the immediate vicinity of the 
 scene of action exhibits no trace thereof. On the other hand, the 
 decomposition of pyrite and associated minerals is here the evi- 
 dent source of heat. Water is plentifully supplied by precipita- 
 tion as well as by superficial and subterranean drainage. If we 
 can assume, and it seems reasonable that we should, that either 
 the supply of heat-producing material had increased without 
 adequate vents for accumulating pressure being in existence, or 
 that the vents, at the time acting as safety valves, were by some 
 means reduced in area of cross-section, then, necessarily, an 
 explosion must follow as soon as the pressure of steam and gases 
 is able to overcome superincumbent weight. Added to this we 
 have learned that decided barometric disturbances were observed 
 on Dominica at a time immediately preceding the catastrophy. 
 In case a bare equilibrium were maintained, certain changes of 
 atmospheric pressure alone might account for a sudden release of 
 gases under pressure. Every indication speaks for the assump- 
 tion that the phenomenon is to be regarded as an explosion and 
 not as an eruption, so far as the latter pertains to vulcanicity. 
 
 In the course of a few years the damages so suddenly wrought 
 will have been repaired again. Plant life in this climate is vigor- 
 ous, and it will seem but a short time ere the now barren slopes 
 will once more be clothed in green. Nothing will remain but 
 some scarred veterans to tell the tale of the disastrous explosion 
 of 18S0. Although a repetition of such occurrences may be 
 looked for, the area is too limited and the seat of disturbing 
 chemical action too superficial to endanger the safety of Do- 
 minica. 
 
LIBRARY OF CONGRESS 
 
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