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Popular Science Monthly/Volume 35/October 1889/Popular Miscellany

< Popular Science Monthly‎ | Volume 35‎ | October 1889


The Function of a University.—President D. S. Jordan has a warning in one of his recent papers against attaching too much significance to numbers in estimating the usefulness of a university. The kind of work that students are doing is the really important consideration. One student in quaternions, or in Germanic philology, or trained to carry a scientific investigation to an end, is worth more than a dozen in trigonometry, or stumbling over the elements in Whitney's Grammar, or learning to analyze flowers or identify the muscles of a cat. Great numbers may mean crowded class-rooms, overworked professors, and drudgery, instead of investigation, and the university a huge machine for lower education rather than a center for the discovery and dissemination of truth. "The highest function of the real university is that of instruction by investigation."


Death of the Rev. M. J. Berkeley.—The Rev. M. J. Berkeley, the distinguished English botanist, died July 30th, at Sibbertoft, near Market Harborough, in his eighty-seventh year. While his knowledge was very general, he was most eminent in cryptogamic botany, and particularly in the province of the fungi, in which he was a leading authority. He was born near Oundle in 1803. Having been graduated from Christ's College, Cambridge, he took orders as a clergyman, and occupied curacies in various places, adding to his income at times by taking pupils, and pursuing during his whole life the scientific researches that have given him fame. His earliest work was among the mollusca, but he soon turned his attention to botany, particularly to the study and classification of the cryptogams. Among his earlier researches were those into the nature of yeast and the vine mildew, the latter resulting in the discovery of the sulphur remedy. His descriptions of the British fungi in Dr. Hooker's "British Flora," published in 1836, constituted for more than twenty-five years the only text-book on the subject possessing any degree of completeness. The portions of Lindley's "Vegetable Kingdom" relating to fungi are also mainly Mr. Berkeley's work, and much of the matter relating to other orders of cryptogams was contributed by him. A more important and comprehensive work was his "Introduction to Cryptogamic Botany," published in 1857. He was associated with Lindley from an early period in the preparation of articles for the "Journal" of the Royal Horticultural Society relating to the influence of parasitical plants on growing crops and the application of vegetable physiology to purposes of cultivation. He was a valued contributor and kind of advisory editor to the "Gardener's Chronicle" from its establishment in 1841 to within a few years of his death; and in it he published a series of articles on vegetable pathology, which have not been collected. His researches on the potato disease made clear that it was caused by a fungus. Travelers became accustomed to submit to him for examination the fungi collected by them, and until within a year or two of his death he continued to publish descriptions of plants of this class from all parts of the world. He is credited by the "Athenæum" with having been among the first to recognize the necessity of studying the whole life-history of the plants before pronouncing a definite opinion as to their place in a natural scheme of classification; and to advocate and practice the culture of them for the observation of the transitions of their forms.


The Yellowstone Park Country.—According to Mr. Arnold Hague, geologist, the country across the Yellowstone Park plateau and the Absaroka Range presents a continuous mountain mass seventy-five miles in width, with an average elevation unsurpassed by any area of equal extent in the northern Rocky Mountains. It is exceptionally situated to collect the moisture-laden clouds which, coming from the southwest, precipitate immense quantities of snow and rain upon the cool table-land and neighboring mountains. The climate, in many respects, is quite unlike that of the adjacent country, the amount of snow and rainfall being higher, and the mean annual temperature lower. Rain-storms occur frequently throughout the summer, while snow is likely to fall at any time between September and May. Protected by the forests, the deep snows of winter lie upon the plateau well into midsummer, while at still greater altitudes, in sheltered places, it remains throughout the year. By its topographical structure the park is designed by nature as a reservoir for receiving, storing, and distributing an exceptional water-supply, unexcelled by any area near the head-waters of the great rivers. The continental divide, separating the waters of the Atlantic from those of the Pacific, crosses the plateau from southeast to northwest. On both sides of this divide lie several bodies of water, which form so marked a feature in the scenery of the plateau that the region has been designated the lake country of the park. Yellowstone Lake presents a superficial area of 139 square miles, and a shore-line of nearly 100 miles. The discharge at the outlet was found in September, 1886, to be 1,525 cubic feet per second, or about 35,000,000 imperial gallons per hour. Dr. William Hallock estimates, from measurements, that the amount of water running into the park and leaving it by the five main drainage channels would be equivalent to a stream five feet deep, one hundred and ninety feet wide, with a current of three miles per hour, and that over an area of four thousand square miles the minimum discharge was equal to one cubic foot per second per square mile. For the preservation and regulation of this water-supply, the forest, which covers the mountains, valleys, and table-lands, and everywhere borders upon the lake-shores, is of inestimable value. Of the present park area about eighty-four per cent is forest-clad, mostly with coniferous trees.


The Glacier of Mount Tacoma.—Relating, in the "School of Mines Quarterly," an excursion to the great glacier of Mount Tacoma, Mr. Baily "Willis describes the glacier, when the party came upon it from the bed of Carbon River, as rising, like a wall of ice, from thirty to fifty feet, across the path, while the river tumbled in little cascades from a low cave in the center. The upper surface of the wall, all its sharp ends having been melted off, was covered with a layer of rock and earth. "I think," says the author, "there can be no better illustration of the advance of a glacier to the point where the melting at its face balances the downward progress, than this worn, shrunken extremity, pressed on as it is by a vast accumulation of ice in the basin between Tacoma and Crescent Mountain. It pushes no great terminal moraine before it. It meets with no obstruction save the narrowness of the cañon; but here in the shadow of the cliffs the air-currents from the west bid it halt." The Crescent Mountain glacial system is fed by slopes which descend ten thousand feet in five miles from the Liberty Cap, Tacoma's northern summit. "Much too steep for snow to lie on, except on the highest shoulders where it packs to a depth of several hundred feet, the upper third of this tremendous height is bare black rock, on which the avalanches shatter into clouds of eddying smoke. The lower four miles are covered with a sheet of flashing ice, which pushes downward over the uneven surface, here carrying huge gleaming pinnacles aloft, there flowing in graceful curves like a river's current. Its western portion comes onward to the cliffs of Crescent Mountain, nearly three thousand feet high, and turning from them sweeps down into the gorge of Carbon River; the eastern part extends a long tongue into a meadow brilliant with flowers, whence White River plunges into its unexplored canon. This meadow is but one end of a green valley that nestles strangely in this region of perpetual frost and sterile rocks, bounded on three sides by ice and snow, and on the fourth by forbidding precipices."


Origin of New Forest Growths.—Observations on the "new growth" of trees that appears after forest fires have been described by Prof. W. J. Real, of the Michigan Forestry Commission. The stubs of most deciduous trees sprout after a fire, and are capable of preserving their vitality for a very long time. Slender oaks, resembling young sprouts, may be found in the forests attached to clumped roots of "grubs" of various sizes, that will show that the present growth is the first, second, third, or fourth sprout that has apparently come in succession from the same foundation. Of three little oaks which were found still having the remains of the seedling acorns attached by the stems of the cotyledons, one was five years old. Others, some four inches high and less than an eighth of an inch in diameter, were shown by the remains of the bud-rings to be from four to ten years old. "It is not difficult to find white oaks under eighteen inches high that are twenty or more years old, and then this may be the second, third, or fourth sprout that has followed in succession, so that it is not improbable that in some of the cases seen the parent root or grub was from sixty to one hundred years old; and the whole now not an inch in diameter anywhere above the ground. Then what shall we say of the age of some grubs that weigh from thirty to fifty pounds each? "Pines and hemlocks will not grow from stumps, but the seeds have a vitality corresponding to that of the deciduous "grubs." In the cone they may be preserved with hardly impaired integrity for five or six years; and cones of Pinus Banksiana have been seen, unopened and apparently perfect, that were ten or fifteen years old. "I feel confident," Prof. Beal says, "that, in an hour or two spent in a certain favorable place, I could fully satisfy any intelligent person, unless he be unusually stubborn, that it is an easy matter to prove that new forests spring from seeds or the stumps of the old, and that, when the second growth is in some respects unlike the first, the change is accounted for in a rational manner."


The Oyster-Garden of Arcachon.—The great oyster-garden at Arcachon, France, is a basin on the Bay of Biscay, connected with the Atlantic only by a very narrow opening, and is sixty-eight miles in circumference and protected from winds by the pine-clad heights that surround it. The waters are salt enough and yet not too strong, the bottom is of the gravelly sand favorable to oyster-breeding, and the rise and fall of the tide are such that the basin is completely covered at high tide and the beds are largely uncovered at low water. The oyster has always been an inhabitant of this spot. The stock had become nearly exhausted forty years ago, but has been recruited by individual enterprise under the encouragement of the Government. There are now 12,500 acres of oyster-beds in the basin. Several thousand men and women are employed to attend them, and the average annual sale of oysters by the principal firm is over 200,000,000. As the majority are not sold under two years old, and these only for relaying, it is computed that there are usually 500,000,000 oysters of various ages upon these beds. The beds having been artificially made, the whole process of oyster-breeding can be witnessed there. They are laid out in parks, each park embracing twenty or more beds, and between the parks, as between the sections of the beds, are water ways for the passage of boats. The beds are made of sand and gravel, upon foundations of wooden piles, and raised above the level of the basin bottom, but not to such an extent as to expose them at other than low tides. A barrier of "switches" or nets protects the beds from fishes. Sets of earthenware tiles are arranged for the reception of the young oysters or "spat," coated with mortar, so that anything fixing itself to them may be scraped off easily. Sometimes each of these tiles will be covered by five hundred or six hundred young oysters. They develop rapidly, and in about a month take the form of real miniature oysters. Then they need more room, and are thinned by scraping, to be placed wider apart on other tiles, or to be transferred to their final beds, or to wire-bottomed trays.


A Navajo Tanner.—Dr. Shufeldt has succeeded in witnessing the complete process of tanning a buckskin by a Navajo Indian. He had difficulty in inducing the tanner to bring his work where it could all be performed before his eyes, because of a superstition that the hide must be removed on the spot where the animal is slain, or the hunter will lose his eye-sight before the next moon. The present hunter, however, perhaps tried to avoid this doom by beginning some of the preliminaries of his work before removing the animal. The skin was taken off with great dexterity in manipulation, and laid in a hole dug in the ground and filled with spring-water till the next morning. It was then taken out, washed, cleansed with a knife, and dipped in clean water. The tools for shaving off the hair wore obtained from the animal itself, being parts of the bones of the fore-leg. The skull of the deer, which had been kept through the night in the ashes of a low camp-fire, was split, and the brains were taken out. They were then manipulated in a basin of tepid water for the removal of splinters of bone, and left to simmer for an hour. When the water, not so hot but that the hand could be held comfortably in it, had become of a muddy color, the tanner took out the brains and rubbed them in the palms of his hands till they were dissolved into a pasty mass. The skin was hung upon a tree and wrung and twisted into a hard coil, and kept in that position for nearly an hour. It had then apparently shrunk to two thirds of its size, and had to be pulled into shape again. This done, it was spread out, hair side up, and thoroughly rubbed with the brain solution. The effect of this was to give it softness and pliancy. The skin, folded into a kind of ball, was wrapped in a buffalo-robe, and exposed for a few minutes to the sun, for the purpose, as the Indian said, of letting "the brains go well into him." It was then unwrapped and spread out to dry. On the next morning it had shrunken again to one third of its original size, was hard, appeared almost brittle, and was half-transparent. It was then soaked in cold or tepid water, washed and rinsed, wrung and "twisted and retwisted upon itself"; again stretched and manipulated into shape, pulled this way and pulled that, worked at the edges to get them limp and pliant, and at the ears and the skin of the legs. "But during all this time an interesting change was coming over it: the heat of an August sun was rapidly drying it, it was fast coming to be of a velvet-like softness throughout, and, attaining its original size, it was changing to a uniform pale clay-color. The hair side was smooth, while the inside was roughish. Indeed, in a few moments more it was buckskin." Then, with the aid of a wooden awl, the tanner stretched the skin of the neck transversely with great force, cut his mark on either side near the ear, and the fabric was finished and spread out for its final drying.


Architecture.—Discussing the question, What style of architecture should we follow? Mr. William Simpson observes that we should follow no style to copy it, or as the ultimate object to be reached, but may use any style with the intention of developing new forms from it. A new style, if we want one—and every people and every age should have its own—can not be evolved out of the inner consciousness of any man or any number of men, but is possible only by practical working. It can only be produced by a course of development requiring time, during which the requirements of the period and the building materials should be the dominating factors. This will produce the constructive forms by a natural process. Then follows the aesthetic or decorative function, in which the artist should be a designer and not a copier. Some style, however, should be taken from which to start. All previous styles have been developments from pre-existing ones. Such has been the condition in the past, and by accepting this we would not be ignoring the experience of what has taken place. The process of adaptation should be begun by weeding out all shams. Let all forms which are not suited to the present wants and conditions be rejected. The same should be done with all constructive forms that are not natural, or which would be bad building if produced with the material employed. No structural form should be added to a building which is not required, and with no other object than that of "architectural effect." This has been a prolific cause of shams. Such things as pinnacles, turrets, towers, and all sorts of useless excrescences have come into existence under this supposed necessity. All decoration which is founded on, or the representation of, previous constructive forms, should be rigidly avoided; and originality in design should be understood as the aim of all decorators.


A Problem in Human Character.—A very paradoxical character is described in the autobiography of Solom Maimon, "vagabond Talmudist," and one of the most learned men and sharpest casuists of the Hebrew race. He appears there, according to the summary of a reviewer of the work, as a "skeptical rabbi, a great Talmudist who despised the Talmud, an omnivorous reader of all such science as in the last century a Polish Jew could get hold of, a genuine idler in literature, who, although he could dash off a considerable spell of work in a short time, had no work in him, had no method in him, and always preferred slip-shod effort to steady industry; a man whom want and misery had reduced into spasmodic fits of intemperance, which rather grow upon him toward the end." With all this he spent a half-year of his life as a regular professional beggar—adopting apparently all the habits and feelings of a beggar. "None the less he was a man of remarkable acquirements, being a learned Tahnudist, for those times at least a considerable mathematician, and having in middle life mastered Latin, German, French, and English, besides the various Eastern dialects of which his Hebrew knowledge was the foundation. He had evidently a very great turn for physics as well as for mathematics, and a wonderful capacity for the acquisition of languages without the slightest communication with those who could speak them, so that he knew a language fairly well of which he could not properly pronounce a single sentence." He so criticised Kant's greatest work as to excite the admiration of the author. In character "he was candid, grateful, generous, and full of kindly feelings. But he was conceited, irreverent, passionate, intolerant of the influence of others, and never really at ease among the class for which his knowledge fitted him. His study of the Talmud. . . thoroughly unfitted him for feeling the least respect for the element of authority in religion." The questions are suggested whether Maimon's vagabond tastes stimulated his intellectual restlessness, or his intellectual restlessness stimulated his vagabond tastes; whether he would have been as keen if he had been a home-stayer and steady worker, or whether it was his taste for wandering and his unsettled habits that really made his intelligence so bright. Much might be said on both sides of these questions; but the probability is, that Maimon would have been stronger and more useful, though, perhaps, less diversified and brilliant, if he had led a regular life.


An Anti-Lightning Cage.—Besides the orthodox or "gather-up-and-carry-away" system of protection against lightning there is another system suggested by Clerk Maxwell—the "bird-cage" or "meat-safe" principle. "In a banker's strong room," says Prof. Lodge, "you are absolutely safe. Even if it were struck, nothing could get at you. In a bird-cage, or in armor, you are moderately safe. . . . A sufficiently strong and closely meshed cage or netting all over a house will undoubtedly make all inside perfectly safe—only, if that is all the defense, you must not step outside, or touch the netting while outside, for fear of a shock. . . . An earth-connection is necessary as well." A wire netting all over the house, a good earth-connection at several points, and a plentiful supply of barbed wire stuck all over the roof, constitute an admirable system of defense. Points to the sky are recognized as correct; but there should be "more of them, any number of them, rows of them, like barbed wire—not necessarily at all prominent—along ridges and eaves. For a single point has not a very great discharging capacity; and, if you want to neutralize a thunder-cloud, three points are not so effective as three thousand. No need, however, for great spikes and ugly tridents, so painful to the architect. Let the lightning come to you, do not go to meet it. Protect all your ridges and pinnacles—not only the highest—and you will be far safer than if you built yourself a factory-chimney to support your conductor upon."


A Giant Earthworm.—An earthworm which, in some examples, reaches the length of six feet, is described by Prof. Baldwin Spencer, in the "Transactions of the Royal Society of Victoria," as existing in Gippsland, Australia. It is the Megascolides australis, one of a group peculiar to Australia, of which five species are known. When found at all it is somewhat abundant, and lives principally on the sloping sides of creeks. At times it is found beneath fallen logs, and may be turned out of the ground by the plow. The worm itself does not appear to leave a "casting" at the mouth of its burrow, but often lives in ground riddled by the holes of the land-crab, which forms a "casting." Hence, contradictory statements have been made about the worm's having a "casting." The presence of the worm underground may be recognized by a very distinct gurgling sound which is made by the animal retreating in its burrow when the ground is stamped upon by the foot. When once heard, this gurgling sound is unmistakable. By its rapid motion and its power of distending any part of its body at will, so as to make it fit very tightly in its hole, the worm contrives to make itself very hard to catch. It has a characteristic odor, somewhat resembling that of creosote, which is very strong and unpleasant in the dead animal. The body, in decaying, passes into a fluid, which the natives of the district say is good for rheumatism. Fowls refuse to touch it, living or dead. When held in the hand the worm, in contracting its body, throws out jets of a milky fluid; and this fluid seems to be the substance which it uses for coating its burrows to make their walls moist and slippery. The worm moves in its burrow by swelling up one or the other end and pulling or pushing itself along from that. Outside of the burrow it does not attempt to get along. The burrows of the large worm measure from three quarters of an inch to an inch in diameter. In disused burrows are often found casts of the worms, and, more rarely, cocoons containing a single embryo. The cocoon is thin, and made of a leathery, tough material, with a very distinct stalk-like process at each end. It contains a milky fluid like that found in the body cavity of the worm.


Fishing in the Greek Islands.—Mr. J. Theodore Bent has been struck, in his visits among the islands of Greece, by the observation of many survivals of ancient ways in the customs of the people, and this very noticeably in the fishing. In fishing for "shell-fish," the fishermen use a long trident, with more prongs than Neptune's had, but otherwise like it, and which they call by the old name καμαξ. The fishermen of Hydra make bulwarks of netted osiers, like those which Ulysses made for his two-decked raft when he left Calypso's charmed island. The scaros is pursued in the way that Oppian sings of in his poem on fishing. Taking advantage of the affectionate character of the scaros and of the male's gallant devotion to the female, the fisherman fastens a female fish to his line. If the "bait" is dead, he imitates life by bobbing it up and down. The male scari rush up in shoals to rescue their female fellow, and are caught by a companion-fisher with a net. For tunny, nets are used having large openings and furnished with a thick string. A bay is chosen with a convenient promontory, from a post on which the nets are fastened, while the fishermen row out to a rock in the sea. Here they leave a man, and return to shore by a roundabout route, carrying a string with them by which they can pull in the net as soon as the man on the rock announces the arrival of the fish. The same method is described by Aristotle in his book on animals. If the market is overstocked with tunny, the fish are driven into a creek by throwing stones at them and the entrance is fastened up with brambles. The fishermen in Melos believe in an ogre called Vanis, a being with goat's feet and a human body—a satyr, in short—who dwells at the end of a promontory they have to pass in going out of their harbor. They always cast a bit of bread into the water as they go by, that Vanis may eat it and send them fish in return.


Studies at Wundt's Psychological Laboratory.—Wundt's psychological laboratory at Leipsic occupies four rooms in the university building. The number of students has gradually increased, and in 1887 was nineteen. The men work in groups, one acting as subject in the experiments, and another making observations. Wundt suggests subjects for research at the beginning of the semester, but he lets the students choose the direction in which they prefer to work, and encourages them to find independently problems and the methods of solving them. The experiments are classified by Dr. J. Mck. Cattell under four heads: 1. The Analysis and Measurement of Sensation. 2. The Duration of Mental Processes. 3. The Time Sense; and 4. Attention, Memory, and the Association of Ideas. Under the first head are included experiments in the least differences in weight, intensity, and tone of sound, illumination, and color that can be perceived—the whole being embraced under the term psychophysics. In the subjects under the second head, constituting psychometry—"the facts obtained when we learn how long it takes to perceive, to will, to remember, etc., are in themselves of the same interest to the psychologist, as the distances of the stars to the astronomer or atomic weights to the chemist"; they help in the analysis of complex mental phenomena, and in studying the nature of attention, volition, etc. Psychometrical experiment has brought perhaps the strongest testimony we have to the complete parallelism of physical and mental phenomena; and "there is scarcely any doubt but that our determinations measure at once the rate of change in the brain and of change in consciousness." There is also a general interest in the study. "Time, like size, is relative. The time-sense, involving the time-relations of perceptions and our power of estimating intervals of time, is to a considerable extent a physiological fact due to inertia in the sense-organ. Stimuli must be separated by a certain interval of time in order that they may be recognized as distinct. The experiments under this head relate to the measurement of these intervals. The experiments in attention, memory, and the association of ideas are varied, and cover some matters included under the other heads. The highest degree of complexity and the lowest degree of intensity and interest which our consciousness can grasp; the number of things—lines, letters, etc.; the relative visibility of colors and legibility of letters of the alphabet; the intervals between maxima of intensity and sensation, or rhythm of sensation; the time it takes for an idea to suggest another; and many similar studies—are related to it.


Inebriate Asylums and their Work.—Dr. T. D. Crothers remarks, as a curious fact, that inebriety was recognized as a disease long before insanity was thought to be other than spiritual madness and a possession of the devil. The first inebriate asylum was opened at Binghamton, N. Y., under Dr. J. E. Turner, after eight years of effort. It was conducted with much success for a time, but went down in the hands of trustees. The Washingtonian Home of Boston, opened in 1857, is now treating about four hundred cases every year. The Kings County Home, of Brooklyn, was opened in 1867, and is crowded with patients. The Chicago Washington Home, opened in 1867, and the Franklin Home, Philadelphia, opened in 1872, are in successful operation. The first two institutions proceed on the theory of disease. The Chicago Home and the Philadelphia Home regard religion, education, and pledges as sufficient to restore the patients, and consider a short residence at the hospital better than long treatment. More than fifty hospitals for inebriates have been started in America, over thirty of which are in successful operation. The others have been changed into insane asylums, water-cures, etc. About twenty asylums for inebriates are open in England and Scotland. Others exist in Melbourne, New Zealand, Germany, and Switzerland, and new ones are projected in Norway, Sweden, and France. The value of the results of the asylum treatment has been estimated from the answers to letters of inquiry addressed to friends of patients several years after dismissal. Of one thousand patients at Binghamton, sixty-eight and a half per cent continued temperate after five years; of two thousand at the Boston Washingtonian Home, thirty-four per cent after from ten to eighteen years; of six hundred at the Kings County Home, thirty-four per cent after ten years. The most careful authorities in the United States are agreed that fully one third of all cases that come under treatment are permanently cured.


The Gnawers of the Selkirk Mountains.—The heaps of bowlders above the forest region in the Selkirk Mountains of British Columbia, says the Rev. W. S. Green, "form a refuge for a variety of mammals—the hoary marmot, measuring about three feet long, being the commonest and most useful from a commissariat point of view. This creature gives a loud, shrill whistle; so weird does it sound in these solitudes that it returns to one's ears as an inseparable memory of the Selkirk valleys. The serrellel is a strange beast; it too lives beneath the bowlder-heaps, and it has the most wonderful fancy for collecting flowers. One day, when we were ascending a glacier moraine, my cousin said to me, 'Some one has been here before.' I said, 'Impossible!' but was utterly puzzled by finding a bouquet of flowers plucked, with their stems lying neatly together, just as though some child had laid them down. Soon afterward we found similar bouquets at the burrows of these animals. What their particular object in collecting flowers is, it is difficult to understand; making hay for winter use I have seen suggested. Mountain rats, chipmunks, little chief hares, and other creatures are also common in these regions, rendering caches of provisions useless, unless tinned meats alone are hidden. My Alpine rope was nibbled into little bits in one night, and on another occasion some beast gnawed a hole through the tent while we were asleep, and ate the bread which I was using for a pillow. A skin I hung up to dry on the tent-rope vanished, and the scampering of little feet up and down the outside of the tent commenced every night the moment we retired to rest."


A Country of Salt.—Everything in the country of the river Chaï, in Central Asia, is described by Gabriel Bouvalot as covered with salt. It is seen in the walls of the houses and on the banks of the rivers, and the water one drinks is very salt. Traveling saltpeter-makers go in summer from place to place wherever they can find materials to work upon. Their mode of operation is a rough-and-ready one. Holes in the earth serve as vats and boilers, and below these are placed ovens. Abundance of brushwood supplies material for the fires. The workers collect from the surface of the earth heaps of a compost of salt and animal manure. This is soaked for twenty-four hours in water, then filtered, and then boiled for twenty-four hours, cleansed, and placed in the sun, so that the water may evaporate. An ordinary workman can make about fifty pounds in a day, and this he sells at the rate of a penny a pound. The workers appear quite contented with their lot, and the industry is preserved in their families for generations.