Popular Science Monthly/Volume 46/November 1894/Redonda and its Phosphates
|REDONDA AND ITS PHOSPHATES.|
REDONDA is a small island lying between Nevis and Montserrat, in that cordon, commonly called the Windward Islands, which keeps the Caribbean Sea apart from the Atlantic, Ocean. It was discovered by Columbus, who named it after an old Spanish cathedral instead of a saint, as he did so many of the smaller West Indies. Some authors, however, claim that Redonda means round, and that it was applied because of the domelike appearance of the island.
In the summer of 1890 the writer had the good fortune to spend a week in the company of Prof. Charles H. Hitchcock on the rock—for rock it is and little else. But the rock contains phosphates, which fact explains our visit to such an out-of-the-way place. I call the island out of the way, because, after being invited by Prof. Hitchcock to accompany him there, we could find no account of it, excepting a casual mention in books on the West Indies. From these brief descriptions the opinion was formed that it was an uninhabited and almost inaccessible rock, furnishing a home only for sea birds. We knew that phosphates were mined there, because we had received specimens from cargoes shipped to this country, but those did not enlighten us with regard to the mode of life upon the rock, and it was with some misgivings that we made our arrangements for a midsummer trip to the torrid zone, with the prospect of roughing it under a tropical sun.
The island was reached by taking the steamship Bermuda, which makes the rounds of the Windward Islands, going to Montserrat and there re-embarking in a small sloop which served as the means of communication between Redonda and the outside world. The sloop was chartered by the phosphate company, and made trips, whenever required, to Montserrat and St. Kitts for mails and supplies. The former island is about fourteen miles away and in plain sight, while the latter is-thirty miles distant, but it is the nearest cable office.
The Bermuda first touched at St. Kitts, and to reach Montserrat it was necessary to pass within four miles of Redonda, and it was with great interest that we watched for it to appear. Approached from the northwest, it presented the appearance of two rounded hillocks, one much higher and broader than the other. No trees could be seen and no signs of life, but some small white objects on the southwest side near the sea and some more halfway toward the summit were thought to be houses.
A sail of three hours in the sloop carried us from Montserrat to the island, which we reached just as the sun was setting on the last evening in June. Viewed from the south, the larger peak only of the island could be seen, and this gave it a domelike yet one-sided appearance, owing to the western side being steeper than the eastern.
A nearer approach to the island showed that it rose from the sea with vertical walls to the height of several hundred feet, with the highest cliffs on the western side. At the southern end was a plateau, back of which rose the domelike peak. At the foot of the western cliffs was a narrow beach covered with large bowlders fallen from above, and here a small pier projected into the sea. As we approached the pier, a boat manned by two negroes put off to meet us, with a strongly built man with pleasant face and brown beard and dressed in white linen sitting in the stern. The man proved to be Captain H——, the superintendent of the mine, who welcomed us to Redonda and transferred us with our luggage to the shore.
The beach was only a few yards in width, and above us towered the cliffs, over five hundred feet high. Groups of men stood on their brink, looking down at us and appearing like silhouettes against the clear sky. Not far from the wharf the cliffs were broken down by a strep, narrow gorge. The ascent to the plateau above was up this gorge, and was accomplished upon an aërial tramway.
Two stout, heavy wire cables were stretched up the gorge and firmly anchored at both ends. Upon each cable ran a trolley, from which was suspended a large iron bucket. To each trolley was attached the end of a light yet strong wire cable, which passed over a set of heavy pulleys at the top of the cliff, thus causing one bucket to ascend as the other descended. When passengers or freight were to be raised, the bucket at the top of the cliff was filled with water from a tank, and the lighter load at the bottom was quickly drawn up. The speed was regulated by means of brakes applied to the pulleys.
The main cables were eight hundred feet long, and the load was raised to the height of five hundred and twenty-five feet above the beach. In places the wires ran at a height of sixty feet above the uneven surface of the gorge.
We were invited to get into the bucket which was at the foot. Captain H—— stood upon the edge, clinging to the trolley, and we rapidly glided up between the steep walls of the gorge, from whose rocky sides peered round cactus plants like heads of gnomes and several strange shrubs threw down aërial roots as though in a vain effort to reach the thin soil at the bottom. On gaining the landing at the top we were received by the workmen drawn up in two lines, bowing and murmuring, "Good ebenin, massa," past whom we were conducted up the slope a hundred yards to the superintendent's house. The dwelling and office were really two separate buildings joined together by a wide veranda between them and along their front. This arrangement made them seem like one house in a climate where doors and windows are unnecessary. The buildings had been brought there framed and ready for putting together, and were small cottages with two rooms and with roofs of corrugated iron. We were met at the house by Mrs. H—— and her young daughter Dorothea, who, with the captain, were the sole white inhabitants of the island. A small black boy called Chalmers showed us to our room, where we prepared for dinner. By this time the short twilight of the tropics had been succeeded by darkness, and when we returned to the dining room with its bright light we could hardly believe that we were upon an almost inaccessible rock in the Caribbean Sea.
The next morning, just before daybreak, while yet dark as night in the room, we were awakened by the cries of the sea birds, which made their homes by the hundreds in crevices and niches of the cliffs. Very soon a bell rang in front of the house to awaken the workmen in the huts below us. A tropical dawn is as abrupt as a tropical twilight, and by the time we were dressed and on the veranda the sun was coming up out of the sea and sending its beams in long lines of brightness over the waters.
The trade wind, with its steady, powerful breath, made the morning delightfully cool, and as we stood looking at the sea far below us, as smooth apparently as a lake, it was difficult to realize that it was the middle of summer in the tropics.
The workmen were now filing past the house on their way to the mine at the northern end of the island. The bookkeeper, an intelligent colored man, stood at the corner of the veranda and, as each, man passed, took his name and checked it in a time book. If a workman failed to have his name checked in this manner he forfeited his day's wages.
The early hours of the morning were devoted to an examination of the phosphate mine, under the guidance of Captain H——. The path to the mine led us along the eastern slope of the island to the northern face of the main peak, where a wide and deep ravine separated us from the smaller peak. The distance from the house to the mine was about three fourths of a mile. The path was very steep in places as it ascended toward the summit in order to avoid a deep gorge, and sometimes so narrow that a misstep would give one a bad fall down the slope.
The phosphate occurred in the form of a cement filling the crevices among the masses of volcanic rock of which the island consists. In places it would be in sheets of the thickness of one's finger between the bowlders, and in others pockets would be filled with several tons. It could be seen cropping out all along the path, but the mining was at that time carried on at the north end for convenience in shipping.
The mining was done by negroes, and both men and boys were employed in the work. The men were engaged in blasting the overlying rock and breaking up the mass of phosphate underneath, while the boys cleaned the phosphate from the gangue and carried it in baskets upon their heads to a wire tramway, by which it was taken to the pile of dressed mineral awaiting shipment. Boys were also engaged in picking out the mineral from small surface pockets wherever a few pounds might be obtained.
The gangue was thrown down the gorge between the two peaks into the sea. While we were there a large bowlder was rolled over for our benefit. It went bounding from ledge to ledge, leaping a hundred feet at a bound, shot over a precipice and struck upon a rock with a loud report, finally splashing into the water. Great quantities of dust were formed by the blasting and digging, and caused much discomfort to the workmen by particles of it getting into their eyes.
The cleaned rock was piled at the head of a gorge which had been broken through the cliffs on the northwestern side of the island. Down this gorge and extending out about fifty yards into the sea was stretched another wire tramway, twelve hundred feet in length, by which the phosphate was loaded into lighters to be transferred from the shore to the ship. The usual anchorage was on the leeward or western side of the island, about four hundred yards from the shore, though deep water extended to within fifty yards of the cliffs.
The phosphate differed in its appearance from any other rock phosphate which I have ever seen. The prevailing color of a pile of dressed mineral was grayish brown, but many lumps were observed of chocolate and ferruginous shades, and many more mottled and streaked with all three; the light-colored variety sometimes shaded to milk-white. The appearance was generally earthy, except with the white variety, which was translucent and resembled flint or opal. The structure was partially oölitic, with many minute cavities, which were usually lined with a white coating. The grayish-brown and chocolate varieties were also frequently amygdaloidal, and the latter kind yielded a few specimens which were beautifully inlaid with ovoidal forms as large as coffee grains, of a lighter brown than the surrounding mass. Most of the phosphate was amorphous; but occasionally the surfaces of hollows or cavities in the pockets and of crevices or seams in the gangue would be covered with the opal-like variety in botryoidal forms of varying sizes, from that of a mustard seed to that of a currant.
The composition of the mineral is that of a hydrated phosphate of aluminum and iron, with a variable amount of silica and other insoluble matter. The commercial article was guaranteed to contain thirty-five per cent of phosphoric anhydride, while the purest specimens yielded about forty-two per cent. Scarcely more than a trace of lime has been found in any specimen.
By the time at which we had concluded our examination of the mine the sun had become very hot, and we returned to the house, where we spent the middle of the day in the shade of the veranda. Perched up there, six hundred feet above the sea, with the water almost beneath us, we enjoyed a view as novel as it was interesting. The air seemed cool, although out on the rocks the heat was scorching in its intensity. The sea, so far below us, looked like a lake just rippled by the breeze. To the east could be seen the low, cloudlike outline of Antigua. Directly in front of us, to the south, lay Montserrat, its nearest headland seeming but a few miles away, and having a white ledge near the sea which resembled the sail of a sloop rounding the point. Once a cloud spun down from the sky in the form of a funnel, and, touching the sea, formed for an instant a waterspout, but there was not enough volume to last. A steamship plowed its way toward Montserrat, and to us, in our rocky eyrie, appeared like a toy. The sea was the same, and yet different every minute.
On the rocks about the house were also objects to attract the attention. Lizards, both brown and green, ran over the ledges and among the cactus, which grew in large masses on the slope below the veranda, while above them might almost always be seen a tiny hawk hovering in the air, looking very much like a martin with its dark-blue back and white belly, but betraying its identity by its movements. Bright green humming birds poised themselves before the red and yellow blossoms of the cactus, and a little insect-eater, in sober brown with a ruby patch on its head, searched busily among the plants.
Several sheep and goats, two dogs, some hens, two peacocks, and a white cat comprised the domestic animals of this Crusoe-like home. From time to time the sheep and goats had become wild and had taken to the almost inaccessible parts of the cliffs and gorges, where it was exciting sport to pursue them.
After lunch, when the sun had begun to descend toward the west. Captain H—— took us down to the plateau below the house to look at the quarters occupied by the workmen. The buildings consisted of two long sheds with close shutters instead of glass windows, and contained for furniture nothing but a tier of bunks, or rather shelves, of rough boards along the walls. Each man furnished his own bedding, which was seldom more than a rude cushion for a pillow. This pillow, together with his other personal belongings, he kept in a box which served him for a trunk.
Near the buildings were ovens where their baking was done by one of their number who served as cook. Their fare was very simple, consisting of bread and salt beef. The foremen and skilled workmen occupied two smaller houses, but lived in the same manner. Water for drinking was obtained by catching the rain on large inclined surfaces of corrugated iron, and collecting it in reservoirs. Such a reservoir was built at each end of the island for the use of the men, and the superintendent's dwelling was provided with capacious tanks connected with the roof.
We were on Redonda just at the time of the full moon, and there was something about the beauty of a moonlight night on that rock which can not be put in words. The sea sparkled with silver gleams as we looked down upon it. Montserrat's rugged outline could be dimly seen, with lights twinkling here and there on its hillsides. Below us the workmen could be heard singing and dancing to the sound of a tambourine. After the hot glare of the daytime everything seemed to be enjoying the delightful coolness of the trade wind. Indeed, so cool was it that it caused me great surprise to find the thermometer registering seventy-eight degrees.
The second morning we descended to the beach by means of the tramway, and at Captain H——'s suggestion I stood upon the edge of the bucket and clung to the trolley. It was exhilarating to glide swiftly down through space, with the cliffs close beside us and the beach far below, yet it was with a breath of relief that I sprang from the bucket to the ground when we had reached the end of the wire.
For a distance of about fifty yards the beach had been cleared of bowlders, and room thus secured for two or three small buildings, the pier, and woodpile. The wood was all brought from Montserrat aboard the sloop. An engine and pump raised water from the sea to the cliffs above, to serve as ballast for the buckets of the tramway whenever passengers or goods were to be taken up.
Entering a boat manned by two negroes, we were rowed along the western side of the island from one end to the other. The cliffs on this side showed a beautiful system of stratification, consisting of alternate layers of solid trap rock and coarse volcanic sand extending from the sea up the whole face. These strata were not horizontal, but in the form of broad arches, the largest of which could only be compared to the rainbow for magnificence of extent. In one place was to be seen a fault, where the upward pressure which formed the arches had caused one to break and the trap rock had been forced upward through three other strata. At the southwest side of the island the sea was gradually washing out the lowest stratum of sand, leaving low arched caverns like the entrances to vaults.
At several points about the island masses of rock resembling the pinnacles and buttresses of a Gothic cathedral appeared to have been thrust up by the upheaval which had caused the bending of the strata. Rude, arched openings extended into them or through them, and one cavern at the north end, nearly forty feet in height, seemed the portal to the very center of the rock. The sea dashed into this opening with a loud noise, and, as an unusually large wave thundered against the innermost walls, a jet of water gushed outward from a small blow-hole in the western cliff, about forty yards from the mouth of the cavern and at a man's height above the sea.
The colors of the cliffs were various shades of gray and ferruginous. The smaller of the two peaks was of a light ferruginous, while the main peak was grayish white.
Perched upon the rocks, and sitting in rows along the gunwales of the lighters, were hundreds of birds. Terns were the most numerous, and were apparently limited to two species which congregated in different parts of the cliff. A black and white species chose the western side, while a blue species, resembling in color a blue pigeon, built its nests on the southern. The nests were mere bunches of grass and feathers, and were so carelessly placed on the shelves of rock that both eggs and young were often found on the beach. Ducks with black bodies and white heads were plentiful, and frigate birds with wide-spreading wings sailed overhead, reminding me of our osprey or fishhawk.
The sea around Redonda was very clear, and Captain H—— gave us an opportunity to look through a water glass. The instrument consisted of a long, narrow box, open at one end, and closed at the other by a piece of plain glass. The box was slung over the side of the boat, with the glass end submerged; and on putting one's face at the open end a new world was revealed below the surface. From two to five fathoms below us the rocks were covered with sponges and corals, and strange fishes swam calmly among them. One large fish was a beautiful creation of purple and silver, and there were many of the red and gold fish so often seen in an aquarium. These latter were the principal food fish of the region. The anchors and chains to which the tram wires were moored were covered with a dense growth of seaweed, which looked very pretty in the sunlight streaming down through the water.
The third day was spent upon the eastern side of the island and upon the summit. Two gorges ran down the slope, beginning nearly at the top. One was covered over much of its surface with fragments of whitish rock, and ended in a cliff a hundred feet in height. The other was the widest and steepest gorge about the island, and extended to the sea; however, it was impracticable of ascent, because of its steepness and its situation on the windward side of the island. The sea was steadily carving away the slope, and had made a deep bay with cliffs on either side three hundred feet high.
The climb from the cliffs at the edge of the island to the summit was very fatiguing on account of the steep ascent. In shaded spots among the rocks beautiful gold and silver ferns grew abundantly, and there were occasional holes where rain had settled which afforded water for the wild goats and sheep. Almost at the summit was the remnant of a deposit of guano. The deposit was never a large one, but it led to the discovery of the mineral phosphate. A few air plants, a species of Tillandsia, clung to the projections of the rocks and formed almost the sole vegetation at the extreme summit. The apex did not consist of a solid mass of rock, but was a pile of huge bowlders without the phosphatic cement of the lower slopes. Looking down the almost vertical western wall, it seemed as though one could leap into the sea one thousand feet below. From this point could be seen Nevis, to the north and near by; while in the distance was St. Kitts with its cloud-capped Mount Misery.
One of the drawbacks to exploring the island was a variety of cactus which the workmen spoke of as "suckers." It resembled the prickly pear in form and had a yellow blossom. Its joints or sections were thickly covered with thorns or spines, which were from three fourths of an inch to an inch and a half in length and barbed at the tip. The joints were easily broken off, and clung to anything upon which their spines could catch. The animals about the place were almost always seen with from one to a half dozen of these "suckers" clinging to them. When a barbed spine became imbedded in the flesh it produced a sore unless removed at once, and it was usually necessary to cut it out in order to remove it. The phosphatic soil and hot sun seemed peculiarly fitted to its growth, and it formed the principal vegetation of the eastern slope. Ordinary domesticated plants of the temperate zone rushed to a speedy maturity under the same conditions.
The remainder of our stay was spent in collecting and preparing specimens of the phosphate, and also of the plants and animals. The negroes brought us many lizards and some big land crabs, and were especially requested to procure us some centipeds and an iguana which were said to be occasionally seen among the rocks. They failed, however, to bring us any during our stay, though subsequently an iguana was sent to Prof. Hitchcock by Captain H——.
The glorious Fourth came while we were there, and Captain H—— favored us in the evening with a display of signal fires and rockets. The compliment was highly appreciated by us, and also by the workmen, who sent up a vigorous shout from their quarters below as each rocket went off.
On Sunday morning, after breakfast, the workmen were summoned by the bell to meet in front of the house and answer to their names. In order to have better control over his men. Captain H—— had devised the arrangement of dividing a man's weekly wages into seven portions instead of six, and obliging him to report at roll call on Sunday or forfeit his weekly earnings. This method put them on their good behavior during this day as well as the others, whereas they had previously claimed Sunday as their own in which to do as they pleased. It was an interesting sight to see the line of black faces, varying in intelligence from refinement to brutishness. The foremen and skilled workmen were dressed in neat white shirts and trousers, serge or linen coats, and polished shoes, and had bright, strong features. Nearly all the men had changed their working garb of shirt and overalls for clean shirts and trousers, and had their usually bare feet covered with shoes, to which they seemed painfully unaccustomed.
As the roll was called I was astonished to hear the names Michael and Patrick coupled with Sweeny and Burke, names very familiar to my ears, but there responded to by men with shining, ebony faces. On inquiry I learned that these men belonged in Montserrat, which was settled over a century ago by Irish refugees, whose family names had descended through their slaves to these miners.
The men were mostly procured from Montserrat and St. Martin's, and were engaged for a term of three months, at the expiration of which they were at liberty to go home if they chose, or were discharged if no longer needed.
On that Sunday there were one hundred and one people on the island, of whom five only were white. However, this proportion of black to white was no greater than in the neighboring islands.
In the afternoon, while taking a nap, I was awakened by what I vaguely thought to be the thunder of a coming storm; but it proved to be Chalmers trying to drive a goat off the iron roof, to which it had sprung from the steep incline behind the house. Though it was now the beginning of the hurricane season, the weather was calm and fine during our whole stay in the tropics.
On Monday the brigantine Foley arrived for a cargo of phosphate, and we went to the lookout west of the house to see her drop anchor. We were at least six hundred feet above the sea, and as the vessel lay in the shelter of the cliff she looked like a boy's ship floating on a pond. The wind was blowing briskly at the time, but the island afforded a perfect shelter against it, and the calm area could be seen extending like a shadow over the sea for half a mile. This protection from the wind also caused it to be almost unbearably hot down on the beach in the afternoon sun, which was reflected from water and cliffs.
On Tuesday, July 8th, we bade good-by to Mrs. H—— and Miss Dorothea, and descended the wires for the last time. Captain H—— went with us aboard the sloop which was to take us to Montserrat. We were soon on our way, and the ensign of Great Britain, flying in front of the house, was dipped three times. We waved a final adieu, and the lofty walls of Redonda were thereafter seen by us only from a distance.