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Caribbean History
Caribbean Area
Economy
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Guadeloupe and Dependencies, The Saints
Guadeloupe and its dependencies (total area ca. 690 sq. mi.) consist of the double island of Guadeloupe (583 sq. miles); the nearer dependencies, Marie-Galante (58 sq. mi.), Désirade (14.5 sq. mi.), Petite-Terre (1.5 sq. mi.), and Les Saintes (5-5 sq. mi.), which form a small archipelago of 11 islands and numerous reefs and islets lying within a radius of about twenty miles to the east, southeast, and south of Guadeloupe; and also St. Barthélemy (St. Bartholomew; 8.3 sq. mi.), 75 miles northwest of Guadeloupe, and the French part of the neighboring island of St. Martin (20 sq. mi.).
Guadeloupe proper (583 sq. mi.), is actually composed of two islands, Basse-Terre (364 sq. mi.) to the west and Grande-Terre (219 sq. mi.) to the east, separated by a mangrove swamp and a narrow tidal channel but linked by a bridge and a road over the swamp.
The Saints and Marie Galante, independent southern members of this group, have already been described as first- and second-cycle members of a simple sequence. The other members of the group are much larger and appear to belong together in a more complicated sequence. Guadeloupe, 24 by 14 miles in extent and 4868 feet high, rises in a youthful, strongly dissected volcanic range; along the southeast coast, where alone I had a passing sight of it, it is flanked by a sloping detrital plain, now more or less trenched by its streams. The west coast is said to have a more abrupt descent to the sea, as if no detrital slope existed there; and this may be, as in the case of Grenada, because the submarine bank on that side of the island is very narrow, probably composed only of volcanic detritus from the island valleys and not representing a previously formed calcareous bank. Grande Terre, closely adjoining on the east, 18 by 15 miles, 354 feet high, is described by Duchassaing as consisting chiefly of volcanic tuffs and marine limestones, raised above sea level and eroded into rolling hills of small relief. A section by Spencer shows the strata of the island dipping gently eastward, with low cliffs on the northeastern shore line where an emerged reef stands six or eight feet above the sea level. The limestone island of Désirade, one by six miles, 912 feet high, with steep sides and discontinuous fringing reefs, stands five miles farther east. A bank of late generation which occupies the northern bight between Guadeloupe and Grande Terre, where many discontinuous bank reefs are found, also extends eastward from the last-named island so as to surround Désirade; its border has the small depth of 20 or 30 fathoms.
No safe conclusions can be reached at present regarding the physiographic evolution of these islands, but it may be briefly suggested that they are now in a third cycle of development. The first cycle probably witnessed the deposition of their calcareous strata, presumably on an early formed and subsiding volcanic foundation wholly submerged before the cycle closed. The second cycle was introduced by a slanting uplift which gave the strata of Grande Terre a slightly more pronounced dip to the east than they now possess, thus initiating the erosion of the uplifted areas; the eruptive growth of Guadeloupe may be associated with this uplift. The third cycle was introduced by another uplift with a very gentle slant to the west, as testified by the present greater height of Désirade over Grande Terre. This westslanting uplift is confirmed by the uplift of Marie Galante a little farther south, while the Saints, to the west of that island, appear to have suffered continuous subsidence. Although the uplift of Marie Galante is like the uplift of Désirade in being greater than that of the islands to the west, the date of the Marie Galante uplift would seem to be much the more recent of the two; for no significant submarine bank has been formed around it, while the bank that connects Désirade with Grande Terre is so large as to indicate the lapse of a considerable period in its production, either by abrasion or by aggradation. It is possible that Grande Terre and Désirade are the eroded and abraded remnants of a single atoll-like bank of the first cycle and that the present bank represents the rest of the earlier bank, converted into a bank of second or third generation by lowlevel abrasion in the Glacial epochs and more or less aggraded in Postglacial time. The mountainous volcanic range of Guadeloupe appears to be, as above suggested, a late and irrelevant addition to the western part of the bank.
Basse-Terre is high, rugged, and volcanic, second only to Dominica in elevation among the Lesser Antillean islands. The old volcanoes, which average almost 3000 feet in altitude, have been much eroded and are dissected by deep ravines. Mt. Soufrière (4867 feet), the highest, is apparently dying or dormant but has several fumaroles and hot sulphur springs. The coast line of Basse-Terre is varied, with great cliffs, swamps, sandy beaches, and numerous indentations, but no good harbors. Even at the town of Basse-Terre, the capital, ships must anchor off shore.
Grande-Terre is very different. Formed of thick beds of limestone deposited on an ancient, eroded volcanic base, the island has a maximum elevation of about 400 feet, and its surface is generally level.
There are some coral reefs around both islands, especially Grande-Terre. The principal port and most important commercial city, Pointe-à-Pitre, is in Grande-Terre, on the Petit Cul-de-Sac, the southern of the two bays that separate Basse-Terre from Grande-Terre.
There are many torrential streams on Basse-Terre, some of them flowing through deep ravines with numerous falls. On Grande-Terre rivers are lacking because of the dryness, low elevation, and permeable limestone, although some ravines have been cut in the limestone and streams flow through them during the hard rains. In the dry months the inhabitants of Grande-Terre are obliged to collect water in cisterns.
CLIMATE
The average sea-level temperature in Guadeloupe is 79° F. The coolest month is February (74.8°), and July and August are the warmest (81.8°). The highest recorded temperature at Pointe-à-Pitre is 90.5° (July), and the lowest 61° (February). There is little difference in temperature from place to place on Grande-Terre, but on Basse-Terre the mountains are considerably cooler than the lower levels (Camp Jacob, at 1738 feet, has an average year-round temperature of 71°). Basse-Terre is wet, with 72 inches of rain falling annually at sea level even on the leeward coast and 204 inches at Camp Jacob, where there are 290 rainy days on an average each year. Some of the higher mountain peaks are nearly always cloudcovered and rainy. By contrast, Grande-Terre is relatively dry, with an average of only 69 inches of rainfall yearly. On both islands the rainiest months are in the fall and the driest period runs from December through April. The winds are generally from the northeast and east during the winter and from east and southeast, with frequent calms and variable breezes, during the summer. There is a hot wet season from May to November and a warm dry season from November to April.
THE SAINTS, EMBAYED AND CLIFFED RESIDUALS
The Saints, south of the lofty island of Guadeloupe, represent a well advanced stage in the firstcycle sequence of small-island development. They are the separated residual summits of an elaborately dissected and partly submerged volcanic mass about five miles across over all, which rise with cliffed headlands from a rimless bank eight or ten miles in diameter and from 30 to 40 fathoms in depth at its outer border. Here the mature subaerial sculpturing of the residuals is manifestly the work of a much longer period than that required for the abrasion of the immature headland cliffs. It is therefore believed that the Saints show in their well carved summits and slopes the work of a long continued interval of subaerial erosion on a slowly subsiding island, which was protected from wave attack during nearly all of that interval by an upgrowing barrier reef; and that the rimless bank which now extends around them represents the reef and its enclosed lagoon floor, as modified during the Glacial epochs by low-level abrasion, which also accounts for the immature headland cliffs, and during Postglacial time by aggradation. The fact that the cliffs plunge somewhat below present sea level, as shown by the charted depths near them, gives support to this view. The submergence of the carved island and the conversion of its summits into separate islets are ascribed to subsidence, not to Postglacial ocean rise, because the amount of carving and probably the depth of carving also--for the slopes of the islets have the appearance of pitching down to a considerable depth below sea level--seem to be much too great to have been accomplished by low-level erosion during the Glacial epochs.
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