In all these various kinds of geographical situation they are found, their production and exhibition being subject to necessary geological and other conditions, on which it is not the purpose of this paper to enter.

The frequent association of these products with salt has been noticed. The oilfields of the Punjab, which have lately been surveyed and reported on, are all in the north-west part of the broken series of hills and tract of country bearing the general name of the Salt Range, containing the inexhaustible stores of massive salt from which that province and neighbouring countries have been supplied for many centuries. The explanation of the connexion of salt with petroleum has yet to be sought, but the fact meanwhile is important.

The oil is not always accompanied with gas, but the inflammable gas appears generally, if not always, to indicate the existence of the oil in some form, and particularly, as it appears, in regions producing salt.

The oil is obtained, as in Burmah, by making excavations in the soil in which it has become diffused, into which excavations or wells the oil slowly passes from the soil around. And it is procured by deep borings, in which it may rise in the manner of water in artesian wells, by hydrostatic pressure, or, as in the many instances with which descriptions of American and other oil-wells have made us familiar, forced up from reservoirs in subterranean cavities under the pressure of steam or other vapour. In any geographical situation it may be obtained in the first manner. It is when it occurs along the outskirts of mountain-ranges that it may rise as in artesian water-wells; and where the earth has been subjected to violent internal action, and the rocks have been much split and displaced, it is obtained from cavities and veins, frequently attended with escape of gas at the surface of the ground and spontaneous discharges of the oil.

These appear to be, in a general way, the kinds of situation and the modes in which, where these products have been formed, they are obtained for use, or where the surface-indications of their presence occur. It is desirable that further

and more definite information should be gathered by those whose experience of oilregions, or other opportunities, afford them the means of contributing to our knowledge of a subject which has come to be of great practical importance as well as of scientific and general interest.

On the Formation of Sand-bars. By Dr. R. J. MANN.

Report on Badakolan. By PANDIT MANPHAL, C.S.I.

On the Eastern Cordillera, and the Navigation of the River Madeira.
By C. R. MARKHAM, C.B., Sec. R. G.S.

The author began by referring to the paper which he read before the Association at the Leeds Meeting in 1858, and in which he showed the vast importance of the opening up of lines of water communication between the Andes and the Atlantic by way of the Amazons, and the immense extent of country which then remained to be explored. Having pointed out what has since been done in the way of discovery, he proceeded to give an account of the recent investigations connected with that portion of the mighty eastern Cordillera of the Andes which contains the sources of streams that form the Beni, and to report upon the operations which are in contemplation, with a view to opening a navigable route from the Beni to the Atlantic by way of the river Madeira. The old Yncas of Peru did all that was possible to secure for their people the wealth of those interminable forests to the eastward of the Andes, but they did not know that the rivers dashing down from their mountains led to an ocean whence the arts and products of the whole world might be brought to their doors. But their descendants see, in the mighty Amazon and her tributaries, a means of saving the ruinous land-carriage of their merchandize to the Pacific coast. The cost of taking a ton of merchandize from Cuzco, the capital of the Yncas, or from La Paz, the commercial capital of Bolivia, to England, is about £40, the time five months. Under such conditions no produce but gold, silver, and chinchona bark would pay the expense

of transit. By the route of the Madeira and Amazons, this voyage of five months will be reduced to six weeks, the course being through a civilized empire which takes the lead in opening the way for the commerce of the world; while the opening of those great fluvial highways will also have the effect of solving the most interesting questions in South American geography. The section of the Eastern Andes, which is drained by the feeders of the Beni, extends from the parallel of Cuzco to that of La Paz. This eastern chain forms a giant wall, running up into the loftiest peaks of South America in its southern portion, and everywhere rising above the line of perpetual snow. The author showed that the cartography of the south-eastern end of the chain is well defined in our best modern maps, while that of the north-western portion is in a state of much confusion; and he also pointed out some analogous features which exist between the Andean and the Himalayan ranges. He then described in some detail the physical features of the region, which is peculiarly interesting, leading to the conclusion that the complete examination of the great affluent of the Madeira will result in opening up one of the richest countries in the world, provided that the question of turning the rapids of the Madeira, and of making the lower part of its course navigable, is grappled with and overcome. The Brazilian Government is alive to the importance of developing the resources and fostering the trade of the Amazon valley, and has caused an elaborate survey to be made of the Madeira rapids. These are eighteen in number, the total fall being 272 feet. The length of the river course, containing rapids, is 229 miles, and the length of actual broken water is 12 miles. The difference between low water and floods is about 20 feet, the rise commencing in October and ending in March. Commerce is now carried past in launches and canoes carrying from 3 to 8 tons. At six out of eighteen rapids it is necessary to haul the boats round overland, at five others the boats are hauled up stream while the boats are carried round, and the rest are merely difficult passes where the loaded craft easily shoot along the current. Serious steps have now been taken to overcome these obstacles. A concession has been granted for the construction of a railway round the rapids, which will be 170 miles long, including a short branch to the mouth of the Beni. Above the Madeira rapids there are 3000 miles of river suited to steam navigation; and the articles of commerce, which would at once find an outlet by this route, are Chinchona bark, India-rubber, vanilla, sarsaparilla, balsams, aloes, valerian, dye-woods, gums, wax, hammocks and bats, cacas, coffee, hides and tallow, wool, skins, cotton, gold, silver, and copper. Commerce is already treading close on the heels of discovery; and Peruvian bark, hitherto shipped exclusively from Pacific ports, is now beginning to find its way to England by the Amazon and Pará. The trade of the Amazons, which was less than half a million when the steamers began to run in 1853, is now upwards of £2,000,000; and this only represents the traffic on the main stream. The increase will certainly be enormous when the mighty affluents bring down the products of the Andes to find their way, by this magnificent fluvial highway, to the Atlantic. The country is one possessing boundless capabilities, and a bright future must assuredly be in store for that great Amazonian basin which nature has blessed so wonderfully. Nothing can be more likely to conduce to the consummation of its commercial greatness than the thorough examination of those splendid navigable rivers which form the chief affluents of the Amazons, and some of the more important of which are still so little known. In no other part of the world is there a grander field for geographical discovery and research. In no other part will the labours of the explorer be more richly repaid.

On the Geographical Positions of the Tribes which formed the Empire of the Yncas. By CLEMENTS R. MARKHAM, C.B., Sec. R.G.S.

In submitting to the Section the views which a study of early writers, the native languages, and the topography of the country had led him to form respecting the geographical positions of the tribes which combined to form the empire of the Yncas of Peru, the author pointed out that the study of the nature and degree of the civilization attained by the aboriginal Americans is especially important, because that civilization was self-developed. The three American empires of the

Yncas, the Chibchas, and the Aztecs were based upon the progress made in the arts of civilization by the tribes which composed them, and on the united efforts of those tribes, after they had been welded into great nations. The difficulties of classifying or distinguishing the special characteristics of the component tribes having been shown, a description was given of the region which formed the empire of the Yncas. This vast tract is a long strip of mountain- and coast-line, bounded on the east by the forest-covered plains of the Amazonian basin, on the west by the Pacific Ocean, and extending north and south from 2° N. to about 20° S., or upwards of 1500 miles, with an average width of 400 miles. It comprises every variety of climate, and contains within its limits the most prolific tropical forests, valleys with the climate of Italy, a coast-region resembling Sind or Egypt, temperate hill-sides and plateaux, bleak and chilling pasture-lands, and lofty peaks and ridges within the limits of eternal snow. On one mountain-side the eye may embrace, at a single glance, sugar-cane and bananas under cultivation in the lowest zone, waving fields of maize a little higher up, shaded by tall trees, orchards of tropical fruits, stretches of wheat and barley, steep slopes clothed with potatoes and quinoa, bleak pastures where llamas and alpacas are browsing, and rocky pinnacles streaked with snow. In such a country, with such a variety of climates and products, and where communication is so difficult, the various nations appear to have gradually developed their capabilities in almost complete isolation. The tribal divisions of the empire of the Yncas agree well with its leading physical aspects. They consist of five clearly defined regions, four following the lines of the Cordilleras, and the fifth on the sea-coast. The first and most northern extends from the river Ancas-mayu to the knot of Loxa, a distance of 350 miles, and is included in the kingdom of Quitu. The second reaches from the mountain-mass of Loxa to the saddle which separates the drainage of the Huallaga and Ucayali. It is 450 miles long, and comprises the Ynca division of Chinchasuyu. The third and most important region is that which is drained by affluents of the Ucayali. It includes the home of the imperial tribe, and may appropriately be called the Ynca division. The fourth comprises the basin of Lake Titicaca, and is known as the Collao. The fifth is the coast-region, and extends along the shores of the Pacific, from the Bay of Guayaquil to the desert of Atacama, a distance of 1200 miles. There is no sufficient evidence for the belief that the Yncas originally came from a distance, and there is a native tradition to the effect that their civilization was altogether of indigenous origin and growth. The author referred successively, and in considerable detail, to the religion, the language, and the architecture of the Yncas, which afforded evidence of, and an index to, the progress of civilization among the tribes. He also briefly described the different regions which comprised the empire, and gave some account of their history and peculiar characteristics. The conclusion arrived at, after careful study, was that the tribes of Peru resolve themselves into two primary divisions, distinguished by a complete difference of language, both as regards vocabulary and grammatical construction, sufficient to establish an entirely separate origin. These are the people of the four Andean regions, and the Indians of the coast. They form two races and two civilizations. The tribes of the four Andean regions, on the other hand, spoke languages which, though differing as regards vocabulary, are identical in grammatical construction, and point to a common origin. The languages are our most reliable guides. Physical differences are caused by local circumstances connected with climate and habits of life. But the languages, when carefully studied, give us an insight into the original condition of the different tribes, and, with the aid of evidence collected from the earliest writers, enable us to resolve the great Ynca Empire into its elements, and to classify its component parts. In a geographical point of view it is important that we should be able to indicate the exact positions occupied by the different tribes, as well as their relative importance, and the degree of relationship they bore to each other.

On the Somali Corst. By Capt. MILES.

This paper contained information regarding the country and its inhabitants, as well as the trade in gum and aromatic spices, in which the natives have engaged

from a very early period. The Somali country is but thinly peopled, the tribes being purely nomadic, raising no corn, but subsisting on their flocks and herds, and moving about for the convenience of pasturage.

Encroachments of the Sea on the East Coast of Yorkshire.
By the Rev. F. O. MORRIS,

On the Inundation and Subsidence of the Yang-tsze River, in China.

By S. MOSSMAN.

The author described the phenomena attending the annual floods of the Yangtsze-Kiang, which are similar to those of the Nile, but greater in inundation, and more devastating in effect. The floods depend upon rainfall from clouds caused by the south-west monsoon rising in the Indian Ocean, and the melting of snow in Eastern Thibet and Kokonoor, where the tablelands are from 12,000 to 13,000 feet above the level of the sea. So far the origin of the floods in the Yangtsze-Kiang is similar to that of the Nile, but the rise and subsidence of the former river are more rapid than those of the latter. The inundations vary more or less in their height from year to year, the range being from thirty-five to fifty feet, while the most frequent rise is about forty feet.

Letters from Vladivostok and Nikolsk, South Ussuri District.
By the Archimandrite PALLADIUS.

On the Geography of Moab. By E. H. PALMER, M.A.

The author commenced by describing the country of Moab, which is about fifty miles long by twenty broad, and includes the tableland on the eastern shore of the Dead Sea, as well as that part of the Ghor which lies on the eastern bank of the Jordan opposite Jericho. The uplands he described as consisting of a rolling plateau, about 3200 feet above the level of the sea, the western edge being cut up into deep valleys, and descending by a series of sloping hills, at angles of forty-five and fifty degrees, into the Dead Sea. These uplands are naturally divided into two districts by the great chasm of Wády Mojib, the Arnon of Scripture. The author gave some interesting instances of his identification of modern places and terms with those mentioned in Scripture history. For instance, he stated that the modern town of Kerek, though little better than a collection of hovels, stands upon the site of the ancient capital of Moab. In the Old Testament it is called KírHaraseth,-Haresh, or Heres. The first part of the name appears to signify "a walled city," but the meaning of the suffix has sufficiently puzzled commentators. But when the author was at Dhibán (the ancient Dibon), he unexpectedly met with an explanation of this term, and it is very curious as an example of the striking manner in which apparently trivial local idioms and customs often illustrate the phraseology of the Bible. Asking one of the Arabs where the Moabite stone was found, the latter replied that it was "between the harithein," that is, between the two háriths. Now, in Arabic this word would mean a ploughman, and when the author asked for a further explanation, the Arab pointed out the two hillocks upon which the ruined village of Dhibán stands, and between them lay the fragments of the broken monument of Mesha. Nearly all the towns in Moab are built upon similar eminences, and the author found that they are invariably called Háriths by the Arabs. The word "Harith" is precisely equivalent in orthography to the haresh, or hareseth of the Bible; and thus, in an apparently insignificant idiom, is seen an unexpected illustration of the topography of the Bible,- -an additional reason for identifying the modern Kerek with the ancient Kír-hareseth ("the city on the hill"), and the interesting discovery of a local Moabite word handed down from the time of Jehoram, son of Ahab, to the present day. The author gave several other curious instances of this kind of identification, and described at some length the investigations of Capt. Warren, Mr. Tyrwhitt Drake, and himself.

On an Acoustic Phenomenon at Jebel Nágús, in the Peninsula of Sinai.

By Captain H. S. PALMER, R.E.

Jebel Nágús is the name given to a high sand-slope in the western coast-range of the peninsula of Sinai, about five miles north of the port of Tor. The sand of this slope possesses the peculiar property of giving forth foud musical sounds when set in motion by design or by natural causes. According to a quaint native legend, founded on the former monastic occupation of this part of the peninsula, the sounds are said to proceed from the nágús, or "wooden gong", of a monastery buried beneath the sand. Hence the application of the name Nágús to the slope in question.

The sand-slope is about 200 feet high, and 80 yards wide at its base, narrowing towards the top; it faces west-south-west. Sandstone cliffs overhang it, and bound it on either side, and an open sandy plain stretches from the foot of the slope to the sea-shore, about three-quarters of a mile distant. The sand of the slope appears to be that from the neighbouring desert plain, derived in the first place from the waste of the sandstone rocks, and then conveyed to its position on the hill-side by the drifting action of high winds; its grains are large, and consist entirely of quartz. The rock in situ is a soft friable quartzose sandstone, of a pale brown inside, and weathered externally to a dull dark brown. The sand of the slope is so clean, and in its usual condition so extremely dry, and inclined at so steep an angle (about 29°) to the horizon, that it may be easily set in motion by such causes as the passage of men or animals across it, falling débris from the cliffs above, or disturbance by the wind. Sometimes also movement on a smaller scale may arise from an abnormal excess of heat and drought, or from the separation of the surface-particles, after their consolidation by rain or dew, on the return of heat and the sun's burning rays. When any considerable quantity of the sand is in movement, rolling gradually down over the surface of the slope in thin waves an inch or two deep, just as oil or any thick liquid might roll over an inclined sheet of glass, and in similar festoons or curves, then is heard the singular acoustic phenomenon from which the hill derives its name, at first a deep, swelling, vibratory moan, rising gradually to a dull roar, loud enough, when at its height, to be almost startling, and then as gradually dying away, till the sand ceases to roll. The sound is difficult to describe exactly; it is not metallic, not like that of a bell, nor yet that of a nágús. Perhaps the very hoarsest note of an Eolian harp, or the sound produced by drawing the finger round the wet rim of a deep-toned fingerglass, most closely resembles it, though there is less music in the sound of the rolling sand it may also be likened to the noise produced by air rushing into the mouth of an empty metal flask; sometimes it almost approaches to the roar of very distant thunder, and sometimes it resembles the deeper notes of a violoncello, or the hum of a humming-top. The author found by experiment that hot surface-sand was more sonorous than the cooler layers beneath; it also seemed to run more quickly; the first experiments on any one part of the slope produced louder effects than subsequent ones. Surface-sand, at a temperature of 103° Fahr., exposed to the sun's full glare, produced the grandest effect observed, while sand in shade, at 62°, was almost mute. By day the heat on the slide is generally very great. Movement of the sand when moist is not accompanied by unusual sounds. Excavation was impossible, on account of the continuous flow of the sand when disturbed; in some places nothing solid could be reached by probing; in others, rock was felt a few inches below the surface, but whether in situ or not could not be ascertained. When sand is rolling down and producing sound, there is a distinct vibration on the slide, increasing with the intensity of the sounds. Throughout Capt. Palmer's stay, the wind blew from N.W.; the effects produced on the slide by winds from other quarters have yet to be observed. Experiments on two other sand-slides, a little to the south of Jebel Nágús, and resembling it in many particulars, did not result in producing any similar sounds. But phenomena of a kindred character had been noticed in other parts of the world, as, for instance, at Reg-Raván forty miles north of Cabul, and on the sandy plains of Arequipa in Peru.

Jebel Nágús had been several times visited and described, but the author had

* Used in place of bells in convents of the Greek Church,