but the formidable and infectious disorder, known, according to the conditions that produce it, as 66 99.66 camp fever," ship fever," "" hospital fever," &c. Its appearance is traceable to the natural disposition of soldiers to shut themselves up in their tents or huts as much and as closely as possible in cold weather. In many camps they have already been allowed to commence a system of suicide by excavating the ground within their lodgings, and throwing up banks of earth against their walls or curtains. This practice, which, as is well known, occasioned a great loss of life in the British army during the Crimean war, should be at once forbidden, and full ventilation of tents at night made compulsory, even at some real or imaginary expense of comfort. Measles and small-pox are also common, the latter sufficiently so to justify uneasiness. The following table shows the distribution, according to statistical classes, of the diseases and casualties of the same portion of the forces of the United States, (1861,) which may be compared with those of the British army when in the Crimea : Number of Diseases and Casualties of each Class and Order to 1,000 cases treated. 2 18 4 8 8 112 24 136 188 51 184 79 85 63 20 83 116 50 166 .... 239 78 817 DISEASES, ETC. Frost.. 1.-1. Miasmatic..... 2. Enthetic 8. Dietic.. 4. Parasitic.. 1000 1000 1000 1000 :~83 158). April 10, 1854, to June 20, 1856. 611 764 678 698 10 84 80 140 678 25 8 Gunshot wound.... 50 18 68 Bite of Serpent... Other injuries of this class. 2. Organs of Circulation.. 8. Respiratory Organs. 8 1 2 2 4. Digestive Organs... 5. Urinary Organs.. 7 8 5 1 6. Generative Organs... 6 2 4 7. Organs of Locomotion... 8. Integumentary System.... 10 2 6 41 34 17 81 82 85 84 } 86 22 80 15 114 ii ARTESIAN WELL AT PASSY. The town of Passy is now one of the western suburbs of the city of Paris, France. It is in the department of the Seine, and enclosed within the new fortifications. The artesian well here was completed in 1861. It is the largest in the world, and, as such, the difficulties with which the engineer, M. Kind, had to contend are worthy of notice. These were brought before the attention of the Academy of Sciences by M. Dumas. The idea of boring this well originated with the necessity of providing pure and wholesome water for the population of Paris, which in a short time had increased from 1,200,000 souls to 1,700,000, thus materially augmenting the causes of infection to which the waters of the Seine are necessarily subject. Paris rests upon a stratum of chalk about 1,500 feet in depth, covered with about 150 feet of various strata of tertiary soil, and itself resting on nearly 150 feet of marl or clay, which is in contact with the green sands from which the well of Grenelle derives its supply. The successful boring of the latter had established the fact that the water which these sands received from localities at a distance from Paris might be made to rise to the surface, and even to 100 and 130 feet above. But the experiment had only been tried for bores not exceeding a diameter of from 8 inches to 1 foot, yielding a supply of from 2,000 to 4,000 cubic metres of water per day. M. Kind came forward with an offer to bore a well of a diameter of 2 feet, yielding 400,000 cubic feet at an altitude of 80 feet above the highest point of the Bois de Boulogne. Though limiting his promises to the yield above stated, he declared his conviction that it would reach 1,200,000 cubic feet, an assertion which most engineers considered exaggerated, deeming it highly improbable that an increase in the diameter would increase the supply. On the 23d of December, 1854, the works were resolved on, and the spot chosen in the neighborhood of the Bois de Boulogne, where the high temperature of the expected column of water might be turned to account. But the enterprise was fraught with difficulties which it required the unflinching perseverance of M. Kind to overcome. On March 31, 1857, the bore had already reached 1,737 feet, and water was hourly expected, when suddenly the tube of sheet iron which supported the clay was crushed by its pressure at a depth of only 96 feet from the top. This accident it took nearly three years to repair; a shaft of the depth of 1,760 feet had to be dug close to the bore, through all the most dangerous strata, and lined partly with sheet, and partly with cast-iron and masonry. Its diameter was about 10 feet throughout the two-thirds of its depth and 170 for the rest. It was a work of extreme difficulty. Cast-iron tubes, of the thickness of four-fifths of an inch, were starred or cracked in all directions, as if they were mere glass. More than once the workmen refused to risk their lives in this work, and the city engineers had to set the example of per sonal courage. This stupendous labor was not brought to an end before the 13th of December, 1859. The old orifice was then cleared, and the boring recommenced, and continued without any further accident to the depth of 1,810 feet, when the tube, composed of wood strongly hooped with iron, and ending in a bronze pipe, 6 feet of which were fitted into the wood, the remaining 39 feet being free, stuck fast in such a way as to render all further progress nearly hopeless. However, M. Elie de Beaumont having, upon a mature examination of the specimens brought up by the borer, declared water to be close at hand, it was resolved that the bore should be continued with a small diameter, to be afterwards enlarged, if necessary. Water was found for the first time at 1,900 feet, but, as we know, remained a few feet below the level of the orifice. A second tube of sheet iron, 24 inches in diameter, in thickness, and 171 feet in length, 40 of which were loopholed in order to let the water pass, was sunk, and soon stopped in the clay. The boring was now resumed, to attain the largest diameter, until the 24th of September last, when M. Kind saw not only his promise fulfilled, but even his hopes to a certain extent realized. The bronze tube has remained where it was, but the concentric one of sheet iron has sunk to 1,250 feet. M. Dumas here quotes M. Michal, Inspector-General of the Works of the City, who has arranged in a table the relative variations experienced in the yield of the two wells of Passy and Grenelle; but on this score we have a later account, stating that the decrease in the latter does not exceed onefourth of its prior yield. That of the well of Passy was 5,660,000 New York gallons in 24 hours. M. Dumas attributes the diminution of the yield at Grenelle to a diminution of pressure, and is inclined to believe that when the tube at Passy shall have been brought to its normal altitude of 256 feet above the level of the sea, the yield at Grenelle will again rise to its former figure, or nearly so. M. Elie de Beaumont has ascertained that the strata traversed at Passy are nearly the same as those met with at Grenelle. As to the chemical nature of the water at Passy, it seems, until further analysis, to be nearly the same as that of Grenelle; the temperature is also the same,-viz., 28 degrees centigrade. Whether other wells may be bored elsewhere in Paris without injury to the two existing ones is a question which experience alone can decide. The well at Passy has cost nearly $200,000. lated at Harvard University, was 17 hours, 7 minutes, 47.76 seconds, and its declination x 59 degrees, 30 minutes, 13.8 seconds. The brilliant comet of July was first noticed at New Haven, Connecticut, on Sunday evening the 30th of June, between eight and nine o'clock, in the northern part of the heavens, in an opening between the clouds and at an elevation of about ten degrees. Its appearance, as described in the American Journal of Science, was similar to that of the planet Jupiter shining through a thin mist; and it was nearly as conspicuous an object in the heavens as Jupiter, although this was due not only to the intensity of its light, but partly to its extent of surface, its apparent diameter being about equal to that of the full moon. It was at once suspected that this body was a comet; but this conclusion was adopted with some reserve, on account of the unusual brilliancy and sudden apparition of the meteor. This light was soon concealed by a cloud; but about half an hour later, a larger opening in the clouds disclosed the tail of the comet, in the form of a bright streamer, with sides nearly straight and parallel, and pretty sharply defined. The head of the comet was now invisible; but a little later both head and tail were seen simultaneously, forming together one of the most brilliant comets of the last fifty years, and astonishing every one by the suddenness of its development. On Monday it was ascertained that on Saturday evening several individuals had noticed in the north a bright streamer, rising to a great height above the horizon, and it was at once concluded that this was the tail of the same comet. The daily newspapers report, that the head of the comet was seen on Saturday evening at Columbus, in Ohio; but it is not known that any one made any accurate determination of its place. On Monday evening, July 1st, it was observed at the Coast Survey Office, in Washington, and its appearance is thus described by Mr. W. P. Trowbridge: "At eleven o'clock last night, while some gentlemen of the Coast Survey were engaged at the office, they observed a broad beam of light stretching up towards the zenith from behind a dark cloud extending over the north western sky. It was supposed at first to be an auroral beam, and but little further attention was given to it till just before one o'clock, when, the clouds having blown off, a comet of extraordinary brilliance was observed in the northwest, the nucleus brighter than a star of the first magnitude, at an altitude of about six degrees above the horizon, and the tail extending towards the stars of the Little Bear, and stretching over an area of at least eighty degrees, the line of the tail making an angle with the horizon of between seventy and eighty degrees. The tail was without sensible curvatare, but in brilliancy and magnitude this comet rivals the great comet of 1858." Professor Bond, at the Observatory of Har vard College, Cambridge, Mass., says: "The suddenness of the apparition of the comet in northern latitudes was one of the most impressive of its characteristics. On the 2d of July, after the twilight had disappeared, the head, to the naked eye, was much brighter than a star of the first magnitude, if only the effective impression be taken into account, although as to intensity it was far inferior to a Lyre, or even to a Ursa Majoris. I should describe the head as nearly equal in brightness to that of the great comet of 1858, between the 30th of September and the 5th of October; it should be considered however that the present comet was better situated, from its higher position above the horizon at the end of twilight. "The aspect of the tail suggested a resemblance to the comet of March, 1843. It was a narrow, straight ray projected to a distance of one hundred and six degrees (106°) from the nucleus, being easily distinguishable quite up to the borders of the milky way." This comet was first seen in Europe on Sunday evening, June 30th, about ten o'clock, appearing with extraordinary splendor. At the same hour it became visible at Rome, Lisbon, Paris, and London. Its appearance in London is thus described: "The comet is, in fact, a very small bodythe diameter of the nucleus, according to Mr. Hind's measurement, being no more than four hundred miles. Its excessive brilliancy is due to its nearness to the earth. When first seen, it was no more than thirteen millions of miles from this planet-and this evening (Saturday, July 6) it will be under twenty-three millions from us. The rate at which it is moving from our point of vision is nearly thirty miles a second-more than a hundred thousand miles an hour. So small an object will very soon get beyond our view. French papers say that this is the comet of Charles the Fifth, which has been expected about this period; but this, it appears, is a mistake. Mr. Hind states that 'the comet arrived at its least distance from the sun about one o'clock on the morning of June 10, in heliocentric longitude 244° 35', being then separated from him by 76,000,000 miles. It crossed the plane of the Earth's orbit from the south to the north side in longitude 279° 1' on June 28, in a path inclined 85° 58' to the ecliptic. The true orbital motion is direct.'" The following communication on the subject was also published: "CRANFORD, July 4, 1861. "Although I watched diligently for a break in the clouds, on Monday, the 1st instant, I did not get a sight of the comet, and it was on the 2d, at 7 minutes past nine o'clock, that I first perceived the comet. The head of the comet was then as bright as a star of the second magnitude, but appeared to the naked eye fully as large as Jupiter, which was visible near the western horizon; the head was almost ver tically over Omicron, in the Great Bear's nose, and during the night retreated almost in the apparent direction of the tail. At about 11 o'clock the tail could be traced for fully ninety degrees; it consisted of a curved brush of light bending over to the direction of the two point ers. The light of this short brush was extremely diffuse on the western side; towards the eastern side a long narrow ray shot out, extended over the zenith, and passed through Draconis, where it again enlarged, and became very faint, but could be traced several degrees beyond an imaginary line, which would join a Lyra and Arcturus. The appearance of the comet in my second Newton's reflector was on the 2d inst. very like a broken fan, supposing the two lower ribs to be considerably curved, and the height of the fan small in comparison with its width. The nucleus, which was situted at the joint of the ribs, was extremely small and elliptical, the longer axis of the ellipse being in the direction of the length of the tail. Last night the fan-shape of the coma was much more distinct and more generally filled with light; but there were several irregular brighter rays within it. The light of the coma and envelope is much more diffuse and less brilliant than Donati's comet of 1858. I made an attempt on the 2d to obtain a photograph of the comet in the focus of my reflector; but not the slightest impression was produced by an exposure of two minutes, although a fixed star was clearly depicted. Yesterday, the 3d, I made several attempts to photograph the comet by means of Rosse's No. 3 portrait lens mounted on the top of my telescope, and carried round by clockwork-not the slightest trace of the comet was depicted in fifteen minutes, although the fixed stars were depicted. As Donati's comet was photographed by similar means in seven seconds, (not by myself,) it follows that the present comet is considerably less actinic than Donati's. WARREN DE LA RUE." Other attempts were made to photograph the comet, but without success. The contigu ous stars left a strong impression on the prepared glass, but the comet itself left no trace of its presence. M. Le Verrier, of Paris, addressed the Academy of Sciences, as follows, respecting this comet: "We do not know this comet; it is the first time it visits us, and those who have endeavored to predict its course, determine its distance from the earth, and measure its tail, have either deceived themselves or the public. Three ele ments are necessary to calculate the orbit of a comet: first, the exact position of the star; then its velocity; and, lastly, the variation of velocity produced by the mass of the sun. I caused the comet to be observed on the 30th of June, and then on the night of the 1st and the morning of the 2d inst., in order to determine the variation of velocity. These three observations would have followed too closely upon each other for the calculation to be at tempted, were it not that the comet moves very rapidly. On the 3d, at 10 A. M., M. Lévy brought me the result of his calculations, and we then obtained an insight into the orbit of the comet. Mr. Hind has since sent me the orbit calculated by the English astronomers, which perfectly agrees, in all but two minutes, with our results. It is now positive that this is not Charles V.'s comet; and, moreover, it resembles none of those already observed. This circumstance will contribute not a little to throw confusion upon the little we know of these erratic bodies. I cannot yet say whether this comet is periodical or not; its orbit up to this day has been too cursorily deterinined to enable us to pronounce it elliptical, parabolical, or even hyperbolical. At any rate, appearances are against its return, for the orbit is nearly perpendicular to the plane of the ecliptic, while those of periodical comets usually form a very small angle with that plane. It is only now we can determine the distance of the comet from the earth, and the length of its tail. On the 30th of June the line joining the centre of the sun with that of the comet made an angle of four degrees with that joining the centres of the sun and earth, the length of which is known. The angle which this line formed with the visual ray, drawn from the eye of the observer to the centre of the comet, was 24°. The triangle thus formed may, therefore, be calculated, and it gives us the distance of the comet from the earth, amounting to between 6,000,000 and 7,000,000 of leagues, (about 17,000,000 of miles English.) The length of the tail might be similarly calculated. The comet is rapidly moving away from us, and it is therefore not surprising that its brilliancy has diminished. On the 10th it will be equally distant from the sun and earth; we shall soon lose sight of it, and astronomers only will be able to follow it for a month longer. It presents a singular peculiarity. M. Chacornac has studied the nucleus with one of M. Foucault's telescopes of a diameter of forty centimetres; instead of its being hollow like the half of an eggshell, like most of the comets already observed, it presents the appearance of a sun composed of fireworks, the bent rays of which burn in the same sense. Moreover, the comet has not drawn nearer to the sun. These are all circumstances calculated to introduce great complications into the theory of comets." The comet as seen at Rome is described by Father Secchi in a communication to the French Academy. The most interesting fact which he relates is that on the 30th of June the polarization of the light of the tail and of the rays near the nucleus was very strong, and could be distinguished by the polariscope in bands, while the nucleus itself presented no traces of polarization, even with Arago's polariscope with a double colored image. But, however, on July Sd, and the following days, until the 7th, the nucleus, in spite of its extreme diminution, exhibited sensible indications of polarization. Father Secchi considers this fact of great im |