SCIENCE.

DR. LIVINGSTONE'S DISCOVERIES.-Rev. O. B. Bidwell, who has made a special study of the subject, has prepared for the ECLECTIC the following account of the present status of the Nile question:-The attention of the whole civilized world has been turned to this renowned traveler by the wonderful events that have recently transpired. His explorations in Equatorial Africa have brought to light some remarkable facts that will tend to settle the "problem of ages." This problem agitated the minds of geographers and travelers before the foundations of modern civilization were laid. Indeed, the process of African discovery has been going on for more than four thousand years; and yet here is a vast region, of which till now we knew absolutely nothing. Longing eyes have been turned toward it, and bold travelers have sought in vain to reach it. The Romans made it a subject of earnest inquiry. Nero dispatched his centurions to solve the mystery. Julius Cæsar said he would willingly lay down the sword if he could only have the glory of discovering the fountains of the Nile.

But this honor has been reserved for the bold and intrepid Scotchman. His discoveries have already gained the admiration of the world, and thus far seem to be a verification of the visions that floated before the mind of Ptolemy at the beginning of the Christian era. Indeed, he only claims to have rediscovered what Ptolemy knew. But the effect is equal to a new discovery, and his name will pass into history as the prince of African explorers.

For the last six years, he has been examining with indefatigable care and study what he believes to be the fountains of the Nile and the great watershed in which they rise. Though long ago reported dead, he is still alive, and has recently been found by Mr. Stanley, the correspondent of the New York Herald, and his wants liberally supplied. Some have doubted Mr. Stanley's veracity in the account he gives of his perilous journey and his visit to Livingstone, but the proofs that his story is true are too overwhelming to be questioned for a moment. He was sent out by Mr. Bennett at an expense of $20,000 to find the lost traveler, and right nobly has he done his work. He merits the gratitude of all mankind for his energy, intrepidity, and perseverance. He has done a good service to science, to civilization, and religion by opening up communication with the lost traveler.

When Dr. Livingstone was lost to the world six years ago, the great question of ages was considered practically settled. Tanganyika had been discovered by Burton and Speke, but its altitude was considered too low to be a possible source of the Nile. Therefore it must find an outlet to the south, and nothing beyond could be supposed to flow to the north. Victoria Nyanza was soon after discovered by Speke, and Albert Nyanza by Baker,

con

both large lakes lying directly under the equator and connected by a river with another outflowing river toward Egypt. The question was sidered settled beyond dispute. The world accepted the new theory that these great lakes were the true sources of the Nile. They were regarded as the very lakes which Ptolemy describes; and doubtless were in part. But according to the facts that are now revealed, most of Ptolemy's lakes and mountains were far beyond these.

Far to the west of Tanganyika lies the great watershed which Dr. Livingstone has discovered, more than 700 miles square, with a drainage to the north; and on it stand mountains 6000 or 7000 feet high, which he believes to be Ptolemy's mountains of the moon. Over this large space he has been traveling back and forth in all directions for the last six years, and made himself familiar with nearly every portion of it. He claims to have found the sources of the Nile between ten and twelve degrees south latitude. Here begins a great and wide valley with a drainage to the north, and in it he has found four large lakes with a broad lacustrine river passing through them all. There is still another lake on the west side which he names Lake Lincoln, and which, by a river flowing out of it, is made tributary to the great central river. These lakes and fountains and rivers spreading over this extensive valley he declares to be in the main 4000 or 5000 feet above the level of the sea.

The fountains or small streams issuing from the mountains far to the south are almost innumerable, so that it would take a man his lifetime to count them. These all unite and form a large river called the Chambezi, which, by an error of the Portuguese, he at first mistook for the Zambezi. This river falls into the first large lake which is called Bangweolo, and which is 150 miles long. After leaving this lake, it is called the Luapula till it falls into Lake Moero. This lake is sixty miles long, and is so completely surrounded by sharp mountains that it is perfectly inaccessible at any time or place, and the river emerges from it through a rocky gorge with the noise of thunder. It is then called the Lualaba till it falls into Lake Kamalondo. After leaving Kamalondo, it is still called the Lualaba till it falls into another great lake not yet explored and which is as yet without a name. This lake Dr. Livingstone now proposes to explore and follow this valley of drainage till he finds out what becomes of this immense quantity of water. For this mighty river, which has so many names, is always broad and deep, being from one to three miles wide even above the first lake. The portions of it between the several lakes are from one hundred to three hundred miles long, though exceedingly crooked, running at all points of the compass in different places and receiving numerous tributaries.

These discoveries have awakened much discussion and great diversity of opinion among geographers and scientific men as to the probable

outlet of this immense body of water. There are five theories put forth respecting it. One is, that it is the Congo flowing into the Atlantic; but this can not be, says the Doctor; for the Congo has its source in the two rivers Kasai and Quango. Another is, that it flows into Lake Tchad near the great desert; but this is quite improbable; for that lake, though eighty miles broad, is nevertheless very shallow, being only fifteen feet deep in the deepest place. And furthermore almost the only river flowing into it from the east is the Shary, which is known to be small and in some seasons nearly dry. Another is, that it flows into a great lake yet undiscovered in the centre of the continent; but such a lake could hardly receive such a mighty river without some other outlet. Another is, that it flows into the Albert Nyanza, which is certainly possible but not probable, as in that case the river flowing out toward Egypt should be twice its present size. The last is Dr. Livingstone's theory that it is the Nile itself. He maintains that there can be no other outlet for these innumerable fountains that pour down from the mountains of the south, and all the tributary streams of this broad valley.

This theory seems to be the one most generally received, although some strong points are urged against it. It is said that the Bahr el Ghazal, the western branch of the Nile (Petherick's Nile) is too small to be the continuation of this great lacustrine river. Captain Grant declares that its mouth where it enters the Nile is filled up with tall reeds, and that during some seasons of the year it is scarcely navigable for small boats. It is said also that Dr. Livingstone's river where he left it is only 2000 feet above the sea, and that the Nile at Gondokoro is the same elevation; therefore it could not flow into the Nile. It is said also that the river Uelle, traced by Dr. Schweinfurth, the German botanist, rises in the mountains near Albert Nyanza and flows almost directly west toward Lake Tchad. This of course would cut off any river coming from the south.

The question then still recurs what becomes of Dr. Livingstone's great river? That is the very question to be solved, and no amount of speculation can solve it. It can only be done by actual exploration. And this is the task which the good Doctor has set himself to accomplish within the next two years. Only about 180 miles remained when he was compelled to abandon his work for want of means and travel away east 500 miles to Ujiji, where he met Mr. Stanley. But now, being abundantly supplied with men and means, he has returned to the heart of Africa to complete what he has so well begun, and follow the great river to its mouth, wherever it may be.

of the body is engaged in performing its natural function-as, for instance, the stomach when it is digesting food, the muscles when they are contracting, or the brain when it is employed-an increased amount of blood is sent to the part engaged. This blood is as necessary to action of the part (or organ) as steam in the cylinder of an engine is necessary to motion of the piston.

There is, however, only a given amount of blood in the body at any given time. So that when there is an increased amount of this fluid in one part there is a correspondingly lessened amount in the rest of the body. A familiar proof of this is the heating and flushing of the head when we are engaged in vigorous mental work, while the body is at rest. This is due, of course, to the increased quantity of blood sent to the head. While the coldness of the feet and extremities is equally due to the abstraction of blood from them to supply the active brain. Less generally understood, but precisely the same, is the cause of the indisposition, often inability, for mental work after a hearty meal. The stomach is then engaged in abstracting from the blood the enormous quantity of gastric juice necessary for digestion, and is the seat of a wonderful activity-chemical, muscular, and nervous-all dependent upon the blood. Happily, the brain is not often able to draw from this seat of digestive activity sufficient blood for its work also; but when it does, it is at the expense of digestion-and this is one fruitful source of Dyspepsia.

Presence of blood, then, being a necessary condition and cause of action of a part, it might be inferred that if, from any cause, there remained an increased quantity of blood in the brain, rest or inaction of this organ would be impossible. Unfortunately, the construction of the blood-vessels in the brain is such that, after they have been distended a certain length of time, they lose the power of contracting, and remain gorged with blood, so keeping up mental activity long after it may be useful or desirable. In this condition one may "woo the balmy" hour after hour in vain. The blood-gorged brain will keep up its restless whirl, while its unhappy possessor tosses and tumbles, each additional conscious minute multiplied by dread of the next, and of the jaded, heavy-eyed to-morrow.

Prof. W. A. Hammond, of this city, was the first to demonstrate that, during sleep, the brain is comparatively bloodless; and all that we have said above is based on his researches and studies.

With other modes of treatment, for what is now recognized as a disease, i. e., Sleeplessness, we have, of course, nothing to do. But in showing the reciprocal action of brain and stomach and muscle, it must have been made clear how the blood-gorged brain may be relieved, and refreshing, healthy sleep secured without recourse to soporifics or narcotics.

Through the agency of the stomach, by a light meal of easily digested food taken just before re

tiring, the blood may be withdrawn from the brain and so speedy sleep follow. But this is not, on the whole, reliable, and is, at best, of questionable relative cost.

Muscular Exercise, taken after brain work at any period of the day, will draw the blood away from the brain more efficiently and healthily than any other agent. Dr. Oliver Wendell Holmes tells us that, during exercise, "the muscles suck up blood like so many sponges." Where do they get it from? Obviously, most largely from those parts which contain the most. And so, reader, if you have counted backward and forward and said endless multiplication tables, or watched sheep jump over a wall, or rolled your eyes until the muscles ached, or tried any other or all other of the popular and ineffectual modes of enticing Morpheus, in all of which you are advised to keep the brain at work in order to get it to rest,- -now try a rational plan. Set the muscles at work and so deplete the brain-thus giving its over-strained vessels a chance to regain their elasticity.

Ten minutes' Cumulative Exercise, just before going to bed, is worth more than twenty grains of hydrate of chloral to procure sound, refreshing, healthy sleep. Cumulative exercise-because no other character of exercise uses so much muscular tissue with so little brain-work, and in such a brief time;-and, consequently, no other exercise will so speedily and cheaply produce that engorgement of the muscles with blood, and so secure the comparatively bloodless condition of the brain which we have seen to be necessary to rest of that organ, and thus invite "tired Nature's sweet restorer-balmy sleep."

NEW USE FOR THE STEAM-JET.—Mr. C. W. Siemens, F.R.S., who ranks among the foremost English electricians and mechanical engineers, has lately shown that the steam-jet hitherto used only to quicken the fire in a steam-engine, is capable of improvement, and application to many useful purposes. The efficiency of the jet depends upon peculiarities in the construction of a tube which cannot be popularly described in a few words; suffice it, that the steam rushes forth as a ring enveloping a core of air, and this, with steam of only three atmospheres' effective pressure, will exhaust air as thoroughly as an air-pump. The jet occupies but little space, and is moderate in cost, and therefore can be used in many places where an air-pump would be too bulky or too expensive. The Pneumatic Despatch Tube, by which despatches are sent underground from the City to Charing Cross, is in the whole of its circuit nearly four miles long. The engine and airpump by which the tube was worked cost three thousand pounds; three of the steam-jets now do the same work, and maintain so good a vacuum that the 'carriers' in which the despatches are inclosed travel at the rate of nearly fifteen miles an hour.

By adapting the jet to a double chamber and

exhausting the air, Mr. Siemens shows that water can be raised as readily as by pumping. The chambers are so constructed that as the one empties the other fills, and so the flow of water is continuous. The contrivances made use of for economizing power and multiplying effect are singularly ingenious; and to prevent the noise that would be occasioned by the combined jet of steam and air rushing from the open top of the delivery funnel of the exhauster, a sound-killer' is placed on the top. This sound-killer is a cylindrical metal vessel, containing a series of perforated wooden diaphragms, which have the effect of deadening noise.

In any case where exhaustion is required, the jet may be employed with advantage, and already the manufacturers of sugar see that it will render them profitable service in evaporating cane-juice when in the vacuum-pans. There can be no doubt that it will be largely made use of in the West Indies, where its simplicity will recommend it to a population unaccustomed to complicated machinery. It will also be used for separating the molasses from the sugar; and thus supersede the present expensive and troublesome process.

Another application of the jet is in the production of gas for heating purposes; the blast is admitted under the fire place, and with such economy, that coal-dust of the most inferior quality can be used, while, all other things being equal, the production of gas is doubled, and its quality improved.

ART.

THE Manfrini Gallery, which was at one time the most interesting and varied collection in Venice, is now reduced to fifty-two pictures, and is on exhibition in London. The other pictures have been disposed of, and brought, it is said, upward of £80,000. The pictures now in the collection are those which were bequeathed by the Duke of Manfrini to his grandchildren, and were sent to England with a view to sale.

MR. JOHN STEELL, R.S.A., of Edinburgh, has been engaged upon a bronze replica of his statue of Sir Walter Scott, intended to be placed in the Central Park. The first casting that, namely, of the stag-hound which lies at the feet of the sitting figure, has been some time completed. Three other heavy castings have since been made, and the work is now ready for shipment. By the application of a certain composition the bronze surface has been brought to a rich brown color, with just so much of metallic lustre as serves to enhance the general effect. Judging by the result of experiments which Mr. Steell has been making, the surface thus produced is capable of resisting the corroding action of the weather, so that the statue may be expected to preserve, at least for some considerable time, its present appearance.

IN clearing out the cellars of the Hôtel de Ville, the workmen have found under a heap of rubbish the statues of Louis XIV. and François I., which formerly decorated the Court of Honor, and which were believed to have disappeared forever. The former, the work of Nicholas Couston, has hardly suffered; but the other is in a piteous state. However, a restoration is not considered impossible.

A STRIKING piece of furniture has been found at Aquila, in the Apennines: it is a bisellium or magistrate's chair of bronze, incrusted with silver, and covered with chiseled reliefs and nielli of exquisite delicacy. The four feet are sphinxes; the lateral supports are horses; the back, ornamented with busts in high relief, is incrusted with hundreds of little figures in silver representing hunting groups, combats, landscapes, religious and domestic scenes of great beauty of workmanship. Castellani, the celebrated jeweler, paid 10,000 francs for it; but judges say it is worth more than ten times that much; indeed its value can hardly be estimated. It is to be classed among the great monumental bronzes at the Capitol. A special gallery of bronzes is to be created at the Capitol in the Palace of the Conservators, where they intend to unite every thing fine that the city possesses in the way of bronzes.

The

OLD GREEK SCULPTURES. - A considerable number of sculptures, says the Athenæum, mostly of the architectonic sort, have been delivered at the British Museum, being among the results of Mr. Wood's arduous, ably-conducted, and fortunate researches on the site of the Temple of Diana at Ephesus, the discovery of which is undoubtedly due to his tact, patience, and discernment. His energy has since been successfully employed in bringing to light these fragments, which are of unusual interest in their kind. most important of the works in question is the larger part of a huge frustum of white marble, a portion of one of the remarkable columns in front of the Temple. Rather more than a third of the original surface of this drum has been utterly wrecked; the remainder shows, in high but rather flat relief, a group of figures, about the size of or rather larger than life, the subject of which is at present obscure. Mercury is recognizable by the petasus and caduceus; a seated figure, which may be Pluto, and that of a grand female, probably Proserpine, form the part on our right of the group. A young male figure, with wings like those commonly appropriated to angels, and across whose body a sword is slung at the hip, by means of a sort of baldric, is on our extreme left. The feet of the figures rest on an advanced moulding at the bottom of the drum; thus the shaft appears to have been banded. The style of the sculpture is academically excellent, but far, very far below that of the finest period. The treatment of parts of the naked bodies and thighs, in respect to their surfaces, is very good;

The baron leans from his towered rock,
And sees the peasants and the flock,
And sighing, saith: "Peace lives with these."
While thought as sad in them doth move,
At the fair palace throned above

Their river, and the highland thick with trees.
Peace hovers over the white-draped bed
Where Childhood pillows its bright head;

Sits under leaves of oak and beech,
In shadow figured quaint with lights;
And haunts the cool of sparkling nights,
And sails adown the stream's moon-silvered
reach.

Doth not mankind esteem her dear!
Her eyes with calm shine deep and clear;

Her voice, how strangely sweet it falls!
The flowing of her raiment white
Doth cast around a Sabbath light;
Who would not hasten when her dove-note
calls!

Why seeks she only field and grove?
Are the wild-flowers alone her love,

Whom all the care-worn world desire?
She answers: "I can dwell in cot,
In palaces, in any spot;

But not with folly, selfishness, and ire."

SOPHOCLES AS A PREACHER.-In his work on "Sophocles," contributed to the series of "Ancient Classics," Mr. Collins says:-The Athenian audience, with the joyous instincts of children— ever ready to "make believe”—gave themselves up to all the illusions of the scene and story, delighting, and freely expressing their delight, in the picturesque and ever-shifting series of graceful tableaux, so different from the still life of a statue or a painting. They were "as gods," knowing all the good and evil in the future of the play-such knowledge only increasing the expectancy with which they looked forward to Edipus blinding himself, or Ajax falling on his sword. The manner in which the poet treated each old familiar tale was the test of his art, just as a mod