Popular Science Monthly/Volume 33/July 1888/Popular Miscellany


The Organization of the Geological Survey.—The statement of the organization, business methods, and work of the Geological Survey, prepared by Major J, W. Powell, the director, in response to the inquiries of the Senate Select Committee on the Executive Departments, gives a very detailed account of that bureau. The Survey was organized in March, 1879, with Mr. Clarence King as director, who was succeeded in March, 1881, by Major Powell, The function of the Survey is "the geological survey and the classification of the public lands, and examination of the geological structure, mineral resources, and products of the national domain, and to continue the preparation of a geological map of the United States." For the prosecution of these researches, there have been organized a division of geography, divided into several sections, a number of divisions of geology and paleontology, and several miscellaneous divisions, namely, chemistry and physics, petrography, mining statistics and technology, forestry, illustrations, and library and documents. The funds for the support of the Survey are appropriated by Congress from year to year, the amount for the current fiscal year being $502,240. Before the beginning of each year the plan for the year is formulated by the director, after conference with the heads of the various divisions and sections, and a stated sum is allotted to each head officer for prosecuting the work in his charge. In large measure each chief is an independent investigator, and, since all reports or maps made by him are published under his name, he has a strong incentive to do all that can be done with the money allotted; his work, however, is under the general supervision and control of the director. The fiscal operations of the Survey are in charge of a chief disbursing clerk, and there are twelve disbursing agents acting under his general direction. Nine of these belong to the scientific staff, and merely add the labor of disbursing to their other duties. There is also a class of agents, made up mainly of chiefs of divisions and their scientific assistants, who are charged with the custody of all property owned by the Survey. This class of agents is made so large that each individual may have personal knowledge of every article with which he is charged. Collections of minerals made for study in the several divisions are ultimately transferred to the United States National Museum, with the exception of material that would be useless in a museum. In the division of illustrations, a number of assistants are employed upon drawings and the proof-reading of engravings. There is a photographic laboratory belonging to the division in charge of a photographer who has four assistants. This force does not include that employed in the section of topographic drawing in the division of geography. The labor of preparing the manuscripts for the press, and of careful reading of the proofs of the large amount of the Survey's publications, has made necessary the development of an editorial system. During the year 1886-'87 there was published an aggregate of 4,253 pages of text, illustrated by 350 plates and 327 figures. These publications consist of four classes, viz., annual reports, monographs, bulletins, and statistical papers. At the date of this statement, five annual reports, eleven monographs, thirty-five bulletins, and two statistical papers had been issued. The monographs are in quarto form, the other books in octavo. The custody of the documents distributed through the Survey is vested in the librarian, and accounts are kept of the number of copies received from the public printer, and sold, exchanged, or given away. A printed letter of transmittal, with a blank receipt and an envelope for its return, is sent out with each copy. The Survey maintains a geologic library for use in the prosecution of its work. The library last year contained 19,501 volumes, 26,100 pamphlets, and 8,000 maps. The facilities afforded by this collection are being utilized in the preparation of two geologic bibliographies by the library staff. The librarian has eleven assistants. In the principal office of the Survey, at Washington, there are employed in the work of the Survey from 70 persons in summer to 225 persons in winter, in a building of 78 rooms, on five floors.

"Feeding for Fat and for Lean."—Dr. Manly Miles, criticising the reports under the above title of experiments in pig-feeding made at the Missouri Agricultural College, and the Wisconsin Agricultural Experiment Station, fails to find any practical results in them which are both new and reliable. He quotes some of the results obtained in the extended feeding experiments conducted by Sir John Lawes and Dr. Gilbert at Rothamsted, and points out, among the indications which they give, that the nitrogenous substance of the animal's increase in weight bears no direct relation to the amount of nitrogenous substance of the food consumed. Also, in the words of the experimenters, "that, with an excessive proportion of nitrogenous substance in the food of the fattening pig, we have found there was more of a tendency to grow in frame or flesh, than in other cases; and again, that the larger the proportion of flesh in the increase, the less will be the proportion in it of real dry substance." Further, when fattening foods contain an ordinary amount of nitrogenous substance, "it is their available non-nitrogenous constituents which rule both the amount of the food consumed and the increase in live weight produced." The pigs fed on corn-meal exclusively at Rothamsted did not do well until a mixture of coal-ashes, salt, and superphosphate of lime was given them, but this gave the most satisfactory results both as to the health of the animals and their progress in feeding. In the Missouri and Wisconsin reports of experiments, little attention is given to the proportion of mineral constituents m the food, which Dr. Miles deems an important omission, especially in the case of growing animals, that should make some increase in bony tissue. lie regards corn-meal as undoubtedly deficient in ash constituents, and his own experience has been that, when feeding it alone, the most satisfactory development of muscle as well as bone has been obtained when the pigs had access to some bone-ash, leached wood-ashes, or other similar mineral matters. It is likewise a common practice among farmers of his acquaintance to provide some mineral "relishes" for their pigs when their food consists largely of corn.

Execution by Electricity.—The new law of the State of New York substituting execution by electricity for hanging was drawn in conformity with the report of a commission, consisting of Elbridge T. Gerry, Alfred P. Southwick, and Matthew Hale, which was appointed by the Legislature to investigate the most humane method of inflicting the death-penalty. The report contains, first, a brief history of capital punishment from the time of Moses to the present day; second, objections to the five modes of execution now employed by civilized governments, followed by a discussion of proposed substitutes, with a recommendation of electricity. From the opinions of experts and the results of experiments on dogs, the commission concluded that "death produced by a sufficiently powerful electric current is the most rapid and humane produced by any agent at our command," and that "the apparatus to be used should be arranged to permit the current to pass through the centers of function and intelligence in the brain," resuscitation under such conditions being impossible. As to the appliances, the commission said: "All that would be essential would be a chair with a head and foot-rest, in which the condemned could be seated in a semi-reclining position; one electrode would be connected with the headrest, and the other with the foot-rest, which would consist of a metal plate." The current of electricity might be supplied from the wires used for street-lighting, or from an independent plant at the place of execution. The most effective machines for the purpose are those known as "alternating machines."

Mound-Builders' Units of Measure.—Mr. R. P. Gregg, of Buntingford, Herts, England, has made investigations concerning the units of measure among certain ancient nations, including those of America. He concludes that the Peruvians of the time of the Incas, the Aztecs, Toltecs, and Central Americans, employed a common measure, comprising a foot equal to 113/4 inches English, or a fraction more than the old Roman or Solon's foot, which foot, = 0·298 of a metre, was divided into twelve equal parts. These feet, being to English feet as 100:102, are reducible by simply adding two per cent. The mound-builders' measure, as derived from a curious tablet found in Cincinnati in 1841, and from implements described by Dr. Abbott and the investigators of Ohio mounds, consisted of a foot equal to ten English inches, or 0·254 metres, which was divided into twelve mound-builders' inches, seven of which were equivalent to six Mexican inches. Incidentally, the author has reason to suppose also that the mound-builders' acre, or larger unit of superficial measure, was equal to from 13/8 to 17/16 English acre, with square side of 300 mound or 250 English feet, and that the favorite square and circle areas of 20, 27, and 40 (or 41) acres English, meant 16, 20, and 30 mound acres respectively. A third unit was the prehistoric measure of North America, the inch of which was intermediate between the mound inch and the Mexican inch, and of which the author is not certain whether there were eleven or twelve to the foot. As no mound-builders' measures have so far been found in Central America, Peru, or Mexico, that people are apparently excluded from the presumption of ever having lived there; but from the occurrence of the southern measures along with those of the mound-builders in the latter's country, it would seem to follow "that the mound-builders, and the people allied to, or the ancestors of, the Toltecs, etc., must have, perhaps some two thousand years ago, coexisted and lived together in large parts of America, extending from New York to Ohio and Tennessee, and not been exclusively confined to the mound districts par excellence."

Flower-Farming.—Flower-farming and the manufacture of essences constitute a special industry in southern France. The principal center of the business is at Grasse, in the Alpes Maritimes, but it branches out into other districts. The flowers grown include the violet and jonquil, which are gathered in winter or early spring, roses, orange-blossoms, thyme, and rosemary, in May and June, jasmines and tuberoses in July and August, lavender and spikenard in September, and the acacia in October and November, so that the season may cover three quarters of the year. Thyme, rosemary, and lavender are usually side-products, grown by farmers of the grape and olive, who distill from them inferior essences, which are used to dilute and adulterate those of superior quality. According to Consul Mason, of Marseilles, the best situations for growing perfume flowers are at altitudes of from five hundred to two thousand feet. Flowers grown on such elevated positions are said to be richer in perfume than similar varieties that bloom in valleys and lowlands. The plantations want to be provided with a soil rich in calcareous elements, and to be sheltered from cold winds. The rainfall being scanty, irrigation is necessary. All fancy and "improved" varieties of flowers are discarded, and the natural, simple, old fashioned kinds alone are grown. Middlemen go through the flower districts every day during the season, and deliver the flowers to the distillers while they are yet fresh and crisp. The manufacture of perfumes includes the making of pomades and oils by the process of absorption, and of essences and essential oils by distillation. To make pomade, a square frame or chassis of white wood, about twenty by thirty inches, is set with a pane of strong plate glass. On either side of the glass is spread a thin, even layer of purified and refined grease. These frames are prepared beforehand, and kept for the time of the flowers. This having arrived, the petals are picked from the blossoms and laid so as to cover the grease in each frame. These are piled one upon another so as to fit closely together, when there is formed a kind of tight chamber, the floors and ceilings of which are of grease exposed to the perfume of the flower-petals within. The grease absorbs the perfume, while the spent flowers are removed daily and fresh ones supplied for two, four, or five months, according to the strength of perfume desired in the pomade. The perfume may afterward be extracted from the pomade by alcohol, when it becomes a floral water or extract. Coarser pomades are made by boiling the flowers in the grease, and subjecting the residue to pressure. The spent pomades are used for toilet purposes, and in the manufacture of fine soaps. When perfumed oils are wanted, superfine olive oil is used, and cotton cloths saturated with it take the place in the chassis piles of the grease coating on the glass. Essences and scents are produced by ordinary distillation.

The Best Asphalt.—No artificial mixture of bitumen and calcareous matter, says Mr. W. Y. Dent, in a lecture before the Society of Arts, is so well adapted for the description of asphalt used for road-making purposes as the natural deposits found at Val de Travers and at Seyssel. Its superiority is possibly due to the perfect manner in which, by the enormous pressure to which the deposits have been subjected, the ingredients of the rock have been incorporated. The native asphalt rock consists for the most part of carbonate of lime, more or less impregnated with bitumen, the quantity of which varies from about six to twelve per cent, that from the Val de Travers, in the canton of Neufchâtel, containing rather more bitumen than that of the Seyssel. The prepared asphalt, as sold by the makers under the name of "mastic," is made by crushing the asphalt rock under a steam-hammer and grinding it to powder by edge-runners. The powdered rock is then carried forward by means of an endless screw to cast-iron vessels placed over a fire, in which it is mixed with suitable proportions of fine sand and bitumen and kept constantly stirred for two or three hours, when it is run into blocks weighing about one hundred and twenty pounds. When the mastic is used it is reheated with more bitumen, and coarse sand is added to it in quantities, according to the purpose to which it is to be applied. Co altar pitch is not an entirely satisfactory substitute for bitumen in this mastic, because when hard it is too brittle, and when warm is too soft and sticky.

Geography and its Related Sciences.—Mr. H. J. Mackinder would define geography as the science whose main function is to trace the interaction of man in society, and so much of his environment as varies locally. According to Mr. Bryce, the environment comprises the influences due to the configuration of the earth's surface; those belonging to meteorology and climate; and the products which a country offers to human industry. The first of these categories depends more largely than has been acknowledged on geology, and is related to physiography, which asks, "Why is it?" to topography, which asks, "Where is it?" to physical geography, "Why is it there?" and to political geography, "How does it act on man in society, and how does he react on it?" and itself asks, "What riddle of the past does it help to solve?" We may stop short at any of these questions, but can hardly answer a later one with advantage unless those which preceded it have been answered. Of meteorology, average or recurrent climatic conditions alone—not weather forecasting—come within the geographer's ken. In considering the productions of a region, the distribution of minerals is incidental to the rock structure. The distribution of animals and plants is pertinent in so far as those organisms form an appreciable factor in man's environment, and in so far as it gives evidence of geographical changes, such as the separation of islands from continents and the retirement of the snow-line. But the study of the distribution of animals and plants in detail, and as illustrating evolution, is in no sense a part of geography. Geography and history are related in their elementary stages, but diverge in their higher stages. The geographer must furnish to the historian the ideas and facts in science which he requires, and must go to the historian for the verification of the relations which he suggests. The body of laws governing those relations, which might in time be evolved, would render possible the writing of much "prehistoric" history. Mr. Green's "Making of England" is largely a deduction from geographical conditions of what must have been the course of history.

Water-Spouts in the Atlantic.—Many interesting reports in regard to water-spouts, sighted by masters of vessels during January and February of the Atlantic coast of the United States, have been received by the Hydrographic Office of the Navy Department. Water-spouts are a special class of whirlwinds, and their manner of formation is described as follows in a supplement to the "Pilot Chart of the North Atlantic Ocean" for March: "A layer of warm, moist air at the surface of the ocean happens to have above it a layer of cooler, drier air. This condition of things is one of unstable equilibrium, and sooner or later the warm, light air at the surface rises through the cooler and heavier air above. This process sometimes takes place gradually over large areas, but at other times it is more local, and there seems to be formed in the upper layer a break or opening through which the air of the lower layer begins to drain upward, as through a funnel. Under favorable conditions—that is, when the differences of temperature and moisture and the supply of warm, moist air at the surface are great—this action becomes very intense, and this intensity is still further increased by the fact that as the air rises its moisture is condensed, the latent heat thus liberated adding to the energy of the rising column of air. Now, as this surface air rushes in and escapes upward through the opening thus formed in the upper layer, it takes up a rotary or whirling motion, the velocity of which increases toward the center or axis of the funnel, and a suction or partial vacuum is created, as indicated by the low reading of the barometer at the center of a cyclone or whirlwind. When a whirlwind is thus formed over the ocean, water is often drawn up the center of the whirl some distance, owing to the suction created, and at the same time the moisture in the air is condensed as it rises, so that the name 'water-spout' is very applicable. Indeed, sometimes a spout will burst over a vessel and flood her decks with water, as a cloud-burst does a mountain-side. When a spout is forming, its upper portion is often visible first, seeming to grow downward from the clouds. By observing carefully with a telescope, however, it will be seen that the motion in the column itself is upward, although the moisture in the air which is rising is condensed lower and lower down, thus rendering the whirl visible lower down continually, and making it appear to be actually descending." That part of the North Atlantic from Cuba to the latitude of Philadelphia, and from the Atlantic coast of the United States to the Bermudas, is pre-eminently a region where water-spouts are liable to occur, owing largely to the warm, moist air lying upon the Gulf Stream, and the cool, dry air brought over it by the northwesterly winds from off the coast. Most of the water-spouts referred to were seen within this region. The Office wishes to receive many full and accurate reports of such marine phenomena, in order that knowledge of them may be increased. The most important observations regarding a water-spout are the temperature of the air and water, the reading of the barometer, direction and force of the wind, and the changes which take place in each while the spout lasts; also, the direction of rotation of the whirl, and an estimate of its size, character, and changes of form, with, if possible, photographs or sketches, however rough, of its appearance at the various stages of its formation and progress.

An Ancient Human Foot-print.—The discovery of human foot-prints in volcanic rocks near the shore of Lake Managua, Nicaragua, under circumstances which seemed to assign them a remote antiquity, has been announced for several years. Dr. D. G. Brinton has described, in a paper read before the American Philosophical Society, a specimen of these foot-prints, sent to him by Dr. Earl Flint, of Rivas, Nicaragua. The volcano of Tizcapa, which furnished the material forming the tufas on which the foot-prints occur, is one of several in the vicinity which have long been extinct, and whose craters are occupied by deep and still lakes. Dr. Brinton's specimen was taken from a quarry on the lake-shore at a point where the overlying strata present a thickness of twenty-one feet beneath the surface soil. These strata comprise five well-marked beds of tufa, beneath which is a deposit of clay, and below this four more beds, with other accumulations in the scams, of pumice and volcanic sand. A heavy deposit of tufa, lying on yellow sand, is then reached. This is the last in the series, and bears on its upper surface innumerable foot-prints—some deeply imprinted, while others are but superficial impressions. As to the age of the foot-prints. Dr. Flint believes the yellow sand under them to be Eocene, but the small shells which it contains are deemed by Prof. Angelo Heilprin to be more nearly Post-pliocene than Eocene. In view of this, and the indications furnished by the overlying strata, Dr. Brinton concludes that there is not sufficient evidence to remove the foot-prints further back than the present Post-pliocene or Quaternary period.

The Lake-Age in Ohio.—Prof. E. W. Claypole has investigated the series of events that occurred in Ohio and the adjoining region during the final retreat of the North American glacier, and has thrown into one view what is known of these occurrences. The terminal moraine of the great glacier crosses the eastern boundary of Ohio a little north of the Ohio River, and extends west and southwest, crossing the Ohio River near Cincinnati. The ice here dammed the river, and ponded back its waters for hundreds of miles. The banks of the Ohio at Cincinnati rise from four hundred to five hundred feet above the water; hence, in order that the ice may have been high enough to pass over into Kentucky, it must have had in the bed of the river a thickness of five hundred to six hundred feet. In this way was formed a lake, which Prof. Claypole calls Lake Ohio, occupying a large tract of the low lands on both sides of the main stream and its tributaries, extending on the north to the edge of the ice-sheet, and hence covering a large share of the southern and eastern parts of the State, reaching beyond the site of Pittsburgh, with arms running up the valleys of the Alleghany and Monongahela Rivers. Lake Ohio must have had a length of four hundred miles, measured in a straight line, and a width of two hundred. Its outlet was probably near Cincinnati, and followed the valleys of the Licking and Kentucky Rivers to that of the Ohio below the ice-dam. When the amelioration of the climate caused the great glacier to retreat northward, there must have come a time when the dam had melted down so that the water could flow over it. A channel was quickly cut in the ice, and the foundations of the dam were undermined. Finally, the dam broke, and all the accumulated water of Lake Ohio was poured through the gap. Days or even weeks must have passed before it was all gone, but at last the lake-bed was dry. When the ice-sheet had been pushed back north of the water-shed which separates the streams that flow into Lake Erie from those that flow into the Ohio River, the water that came from the melting of the ice was held between the front of the retreating ice and the ridge of the land. Thus in the valleys of the Cuyahoga, Sandusky, Maumee, and other north-flowing rivers, triangular lakes were formed with their bases resting against the ice-wall, and narrowing and shallowing back to the water-shed, where they found outlets in south-flowing rivers. All these lakes left monuments behind them in the form of beds of silt, in which are imbedded stones such as might be dropped by floating masses of ice. As the ice-line shrank back down the slope toward Lake Erie, the bases of these triangular lakes spread until they came in communication with each other, and the chain formed one continuous lake, using the lowest of the several southern outlets which had belonged to the separate lakes. As the bed of Lake Erie became uncovered by the glacier, this ancient lake increased in extent, and there is evidence which indicates that when the ice-sheet had retreated still farther the lake formed one vast sheet of water occupying the beds of Lakes Erie and Ontario, the southern part of the bed of Lake Huron, and much of the surrounding country. There was no escape for this water through the St. Lawrence River; that pasage was still blocked by the ice. Where Fort Wayne, Ind., now stands, there is a gap in the ancient margin of the lake, two hundred and twenty-five feet above the present level of Lake Erie, but one hundred feet lower than any of the outlets of the chain of triangular lakes which had been the nucleus of this great inland sea. Southwestward from this water-gap runs a broad but now almost deserted water-way communicating with the valley of the Wabash River, and by this passage the drainage of the "Erie-Ontario" basin found an outlet to the Mississippi.

The Head-Waters of the Orinoco.—The Guaharibos, an Indian tribe living near the head-waters of the Orinoco, are described by M. Chaffaujon as of small and mean stature, with slender limbs, stomach inordinately distended, long and coarse hair, and bestial physiognomy. They were absolutely nude, and carried nothing but a stick. Their repast consisted of palm-shoots, a quantity of half-rotten fruit, and some balls composed of white ants. Some others, to whom the traveler exhibited at a distance pieces of cloth, knives, etc., fled as soon as he attempted to get near them. The source of the Orinoco was found to be a mountain-torrent springing from a peak which was named Ferdinand de Lesseps, in the Sierra Parima range (3,300 feet high). M. Chaffaujon studied the remarkable bifurcation of the Orinoco by means of the Cassiquiare, whereby a connection is established with the Rio Negro and the Amazon, and found it to be the result of the undermining and washing away of the clay banks of the river during the rainy season. The outlet from the Orinoco descends a few inches every year, and is now nearly half a mile from its original position. In entering the Cassiquiare the current has the same force as that of the Orinoco, but quickly increases in rapidity after traversing the clay deposits. This communication between the two streams is believed to be recent.

The Progress of Cremation.—It is now fourteen years since Sir Henry Thompson proposed cremation as a method of disposing of the dead eminently desirable to be adopted on sanitary grounds. The proposition fell as a shock upon a large part of the public; and it may be recorded as among the curiosities of the human mind that, although there is no conceivable relation between cremation and religion, it was regarded by many persons high in the Church as a covert attack on Christianity. Yet it was not new; for it had been proposed in Italy in 1866, experimented upon by Gorini and Pollini, with published results in 1872, and illustrated, with the display of a model furnace at the Vienna Exhibition of 1873. The Cremation Society of England was formed in 1874. Opinions of legal authorities were obtained to the effect that the proposed process was not illegal, provided no nuisance was occasioned by it. An arrangement with one of the London cemeteries for the erection of a crematory on its grounds having been vetoed by the Bishop of Rochester, an independent property was obtained at Woking, on which a Gorini furnace was erected. A test of this apparatus, made by Prof. Gorini himself in 1879, showed that in it complete combustion of an adult human body could be effected in about an hour, so perfectly that no smoke or effluvia escaped from the chimney, every portion of organic matter being reduced to a pure, white, dry ash, absolutely free from anything disagreeable. Several cremations had in the mean time taken place abroad; one at Breslau and one at Dresden in 1874, and two at Milan in 1876. The Cremation Society of Milan was established in 1876, and soon became popular and influential. It erected a handsome building, with a gas, and afterward two Gorini furnaces, in which four hundred and sixty-three bodies were cremated to the end of 1886. Similar buildings have been built and used at Lodi, Cremona, Brescia, Padua, Varese, and Rome; and in all seven hundred and eighty-seven bodies have been cremated in Italy. The only place in Germany where the practice has been regularly followed is Gotha, where a building was constructed with the permission of the Government, in which four hundred and seventy-three cremations were performed from January, 1879, to the 31st of October, 1887. Cremation societies have been established in Denmark, Belgium, Switzerland, Holland, Sweden, and Norway, and in various parts of the United States. A crematory has been built in Paris, and was first used on the 22d of October last. The English crematory did not go into operation until 1884, after Mr. Justice Stephen had pronounced his judgment that the process was legal, if performed without nuisance. Suitable provisions were made to obviate the only valid objection to the process—that it might be used to destroy evidences of poisoning—and the first cremation took place on the 20th of March, 1885. Two others followed in that year, ten more in 1886, and ten more to the end of November, 1887. "The complete incineration is accomplished," says Sir Henry Thompson, "without escape of smoke or other offensive product, and with extreme ease and rapidity. The ashes, which weigh about three pounds, are placed at the disposal of the friends, and are removed. Or, if desired, they may be restored at once to the soil, being now perfectly innocuous, if that mode of dealing with them is preferred. One friend of the deceased is always invited to be present, and in almost every instance has expressed satisfaction with the way in which the proceeding has been carried out." The Cremation Society has no thought of making cremation compulsory, but simply by all the means in its power to encourage its voluntary adoption, and to enlarge the opportunities for those who desire it to have their wishes properly carried out. It, however, urges upon all that cremation is eminently preferable—whatever may be the feelings in other respects—in the case of persons who have died of small-pox, scarlet fever, or diphtheria. All cases where the cause of death is in doubt should be rejected at once, except after an autopsy. If the autopsy is objected to by the family of the deceased, the cremationists would avoid the doubtful case without raising an imputation.

India-Paper.—India-paper, which the Chinese call lehi, is made from hemp, mulberry-bark, cotton, bamboo, rice-straw, barley-straw, and from the interior membrane of silk-worm cocoons. Sometimes the whole of the stalks of bamboo of a year's growth are used. The pulp is mixed, after it has been prepared, with a given proportion of a vegetable gum called hotong in China. The paper is molded in molds made of fine bamboo filament. Those sheets, sixty feet in length, which the Chinese are said to make, are supposed to be fabricated by artfully joining several small sheets at the moment of laying the paper. When taken from the molds, the paper is stretched upon a wall, hollow inside and heated, the surface of which has been coated with a very thin mastic. The application of the mastic is made with a brush, and this accounts for the streaks and roughness that appear on the wrong side of this paper. India-paper, being too thin to bear handling or any strain, is mounted on vellum, which serves as a lining to it, and the white borders of which set it off as a frame would do. The sheets thus prepared are kept in a dry place, far away from the fire, and may be preserved for years.