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more convenient one with a folding roof is still open to the same objections as regards bulk, weight, and inconvenience. Yet an artificial horizon is an absolutely essential part of a traveller's equipment, so that any improvement in its construction is sure to be welcomed. Captain George's instrument is stated to combine all the advantages of the larger and more cumbrous horizon now in use, together with the additional property of securing observations at very low altitudes. The improvements are not confined to its reduced size and weight, but extend to its mechanical arrangements, form, and moderate price. The new horizon weighs 1 lb., while that now in use weighs 6 lbs. The self-replenishing horizon consists of two circular disc-like reservoirs, about 24 inches in diameter, and three-quarters of an inch in depth, made of iron in one casting. One contains the mercury, and the other is the trough, fitted with a glass cover for observing. The discs are connected at their circumferences by a narrow neck, with a hole drilled through it, by which the mercury passes from one reservoir to the other, communication being opened or cut off by a stop-cock, without removing the glass cover, or running the risk of losing any of the mercury.

A paper by Major Basevi, On the Minicoy Island, was next read. Major Basevi, who is connected with the Great Trigonon etrical Survey of India, visited the Island of Minicoy, with the object of comparing the intensity of gravity on an island station with that at inland stations in the same latitude. Minicoy is a small coral island, in shape somewhat resembling a crescent,. and about 6 miles long. The whole of the island is covered with cocoa plants, which are the chief source of wealth to the inhabitants, all of whom have their own trees-the rich as many as 2,000. The village of Minicoy is situated nearly in the middle of the island on the west side. It is half a mile long, and contains about 300 houses, built of coral rock, cemented with lime and thatched with palm leaves. The result of Major Basevi's observations on the Island of Minicoy was the conclusion that gravity on the coast is greater than inland, and at an ocean station like Minicoy greater than on the coast. It was already known that at inland stations gravity appeared to be in defect of that observed at coast stations in similar latitudes; and, by including the ocean station of Minicoy in Major Basevi's series, a confirmation of the law has been obtained.

Captain A. Pullan contributed some notes On British Gurhwal, where he had been employed for four years on the Trigonometrical Survey; and Mr. Samuel Mossman a paper On the Inundation and Subsidence of the Yangtze River.

Mr. Clements Markham read a report On Badokshan, by Bandit Manphul; and a description of a journey from Yassin to Yarkhand, by Ibrahim Khan. The most interesting feature in connection with these papers was that they confirmed the surveys of the country made in 1838 40 by Captain Wood of the Royal Navy. Captain Wood, who is a native of Edinburgh, discovered the river Öxus, and for doing so was awarded one of the gold medals of the Royal Geographical Society. surveys were ignored by Prussian and Ku-sian geographers, but were now confirmed by the native travellers who have devoted their attention to the parts of the country in question.

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The Rev. F. O. Morris contributed a paper On Encroachments of the Sea on the East Coast of Yorkshire. It was stated that on the average there had been a loss of land of from two to three yards every year-probably about 24 to 23 yards per annum. If looked at in round numbers, the waste of land, at three yards in each year, would be found to be about thirty-nine acres between Spurn Point and Flamborough Head alone, or in a hundred years of 3,900 acres, which, at a value per acre of 30/ or 50%., would represent a serious money loss of grain or other crops; or, taking the waste, as had been calculated, at one mile since the date of the Conquest (1066), the money value in that interval, at 30l. per acre, would be equal to 691,200/., or at 50/ an acre no less that 1, 152,000/. Mr. Morris concluded by saying there was no doubt whatever that a sea-wall of roughly-hewn, or even unhewn, stones, laid on an angle of about thirty-five degrees, would for ever protect the land from encroachment.

'SECTION F.

THE papers and discussion in Section F are scarcely of a nature to come within the range of a report in NATURE. Occasionally, however, they may well find a place, as when on the first day Sir John Bowring read the Keport of the Metric Committee of the British Association. The Committee were much gratified at the large amount of information the Royal Commissioners had

collected in regard to the metric system, but regretted that the Commissioners had not recommended a bolder course than the permissive legislation of its use. The Commissioners assumed there was no immediate cause requiring a general change in the existing system of legal weights and measures of the country for the purposes of external trade, but they had not sufficiently taken into account the bearings of the question on education and scientific workmanship, and the general economics of the nation. The committee admit that the full realisation of the advantages of the system must be the work of time, but all the more necessary is it to make provision for the same by inserting in any measure on the subject clauses fixing a time when the use of the new system will become binding. Pending the final settlement of this important question, the committee are gratified in finding that the Educational Code of this year for the first time prescribes that in all schools the children in Standards V. and VI. in arithmetic should know the principles of the metric system. The committee are convinced that the school is the proper place for initiating this useful reform, and urge that teachers should at once commence to introduce this subject in the schools. The committee have represented to the London School Board the desirability of introducing the metric system into its schools, and will correspond in a similar manner with other school boards. In order to diffuse information on the subject, the committee suggest that they should be re-appointed, with a grant of at least 75% from the funds of the Association. After some discussion, the report was accepted-it being understood that no opinion was expressed on the compulsory question. On the same day the Report of the Committee for the Tabulation of the Census was read by Mr. Fellowes. It stated that various suggestions had been made to Mr. Bruce, with the view of having the returns from the various parts of the kingdom tabulated in one uni'orm method, and the committee had reason to believe that the recom mendation in their memorial would ultimately, to a considerable extent, be adopted by Her Majesty's Government.

After the reading of Mr. Fellowes's paper On a Proposed Doomsday Book, giving the value of the Governmental property, as a basis for a sound system of national finance and accounts, Mr. T. J. Boyd, master of the Merchant Company, read a paper On Educational Hospital Reform; the Scheme of the Edinburgh Merchant Company. The object of this paper was to illustrate, from what had been done by the Merchant Company in recent years, the manner in which similar foundations might increase their usefulness and extend the benefits contemplated by the founder.

On the following day Col. Sir J. E. Alexander read a paper On Sanitary Measures for Scottish Villages. Among the evils pointed out as existing in these villages were the overcrowding of cottages, the system of "box-beds," in which father, mother, and children might often be found huddled together, the built-in windows quite incapable of being opened, the general want of air and ventilation, and the proximity of cow-sheds and pig-sties. The writer showed how ministers, surgeons, schoolmasters, and employers might promote the welfare of the people by inculcating the laws of health, and promoting a taste for pure and innocent recreations.

One of the most interesting episodes in this section occurred on Saturday, when the reading of a paper by Mr. George Smith, On Indian Statistics and Official Reports, gave occasion to the following remarks on Indian education by a native Hindoo, Mr. A. Jyram Row. A great element in the success of the schemes for the better education of the Indian population was the nature of the education which must in future be given to the natives of India. At present it was certainly of a character calculated to do a great deal of good, but at the same time it was restricted to English litera ure and mathematics. Now, the mere reading of Shakespear, and the mere cramming of a few propositions from Euclid, would never enable people to embrace large questions of speculative and scientific interest, which alone could be expected in the end to lead to any practical result. Without such an education these statistical schemes would seem at first sight to have nothing to do with anything that was practical, unless it were (as some people supposed) that they merely had reference to the imposition of a poll-tax or some such thing. They could not see (and it was not to be expected that people unaccustomed to scientific questions and the bearings of each department of science upon the solution of problems entirely unconnected with the department could see) that such schemes would be of the highest consequence towards the material welfare and progress,

not only of Hindostan, but of every nation on the globe. Therefore, he was of opinion that such an influential body as the British Association would do well to exert its influence in obtaining for the natives of India a more thorough scientific education.

The time of this section on Monday, August 7, was chiefly occupied by debating the administration of the Poor-law Reformatories and kindred subjects not suited to our columns. In a paper on the Scientific Aspects of Children's Hospitals, Dr. William Stephenson endeavoured to show how far their general management tended to promote the twofold object for which they were called into existence-namely, the relief of the children of the poor and scientific instruction in the diseases of children-and what external causes were at work to check the full development of the influences they exerted. He pointed out the importance of such institutions as the Sick Children's Hospital, in the way of extending the knowledge of the diseases of children among students of medicine, and also in the way of training nurses both for the hospital and for the family.

On Tuesday, the paper which excited the greatest interest and most animated discussion was by Miss Lydia Becker, On some Maxims of Political Economy as applied to the Employment of Women and the Education of Giris; and this was followed by one on Naval Efficiency and Dockyard Economy, by Mr. Charles Lamport, and by others on Land Tenure and the Assessment of the Foor, concluding the business of this section.

SECTION G.

ON the opening day of the Association, Mr. Thomas Stevenson, C. E., in introducing the subject of a Proposed Automatic Gauge for the Discharge over Waste Weirs, said that in order to ascertain the amount of available rainfall, which was so important in questions of water supply, it was necessary to gauge the quantity of water which escaped at the waste weirs of reservoirs. Observations made only once or twice a day could not supply the information. He proposed to place a tube perforated vertically with small holes, the lowest of which was on a level with the top of the waste weir, so that whenever water passed over the weir, it also passed through the holes in the tube. The water was collected in a tank capable of holding the discharge for a certain number of hours. The quantity so collected was a known submultiple of what passed over the weir. discharge through the holes was ascertained by experiment.

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In the discussion which followed, different views were expressed as to the practical value of Mr. Stevenson's proposal, which was, however, favourably regarded by Prof. Rankine.

A paper on A New Form of Salmon Ladders for Reservoirs was read by Mr. Alexander Leslie, C. E. The new form of salmon ladders for reservoirs of varying level, a model of which was exhibited, contemplates that on all occasions the whole outflow required to run down the stream should be through only one sluice at a time, and over the top of that sluice, which would open by lowering, and shut by being raised, except in extreme floods, when, for the sake of keeping down the level of the lake, so as to avoid flooding the adjoining lands, or when from any other exceptional reason, such as an accumulation of ice, it may be necessary to provide a lower outlet or the means for a more rapid discharge. Assuming the rise of the lake to be 12 feet, and that it is full, or up to the level of the waste weir, the uppermost sluice is opened, so that the water may flow over it to the depth of, say, from 9 to 12 inches, and then run down the inclined plane of, say, 10 feet in width, composed of a series of pools formed by stops reaching quite across from wall to wall, the fall from surface to surface of those stops being 18 inches, and the depth of each pool being not less than 3 feet. The fish may then easily leap over the successive falls, seven in number, after which they must take the last leap over the sluice into the lake, the last leap being at first like all the rest, 18 inches, but diminishing in height as the level of the lake is lowered, till at last it is nothing, when the level of the lake comes to be the same as that of the pool. The paper went on to describe the process of the working of the machine when the lake gets too low to give the requisite supply of water over the top, and concluded by stating that it would be preferable not to make the ladder above 18 inches. On that point, however, the author did not offer any decided opinion, but left it an open question.

The next paper was by Mr. R. A. Peacock, C. E., Jersey, on A Chain Cable Testing and proposed N. Link. The paper proposed to provide a new testing link, which, it was believed, would be found useful in various ways. The following is a description

for a cable of which the metal would be one inch in diameter :Let the cable manufacturer provide himself with a number of plates of rolled iron, of the same quality as the cylindrical bars of iron of which the ordinary links are made. The thickness of each plate is to be equal to the diameter of the bar from which it is provided. Eight links will have to be punched out of the plates by means of a steam punch. One new link, when filed half round, will be placed longitudinally at each extremity of the cable, with which it will be connected." A new link, after being filed as aforesaid, will be inserted longitudinally at every fifteen fathoms in each cable, so as to form a part or parts of the cable; and each cable being about 150 fathoms long, will require eight new links.

A paper On Road Steamers, by Mr. R. W. Thomson, Edinburgh, was read by Mr. Miall. In the outset, the paper alluded to the importance of road steamers and the difficulties which had been encountered in arriving at the present stage of perfection with these machines. A uniformity in the working of the engine having been reached, a thick carpet of india-rubber for the tires of the wheels was introduced, which much improved the running on roads. These india-rubber tires not only completely prevented hard shocks to the machinery, but saved the road from the grinding action of the iron wheels which was so injurious to by-ways. There had been serious objections made to the use of these engines by people interested in the roads, but the author could assure them that the india-rubber tires actually improved the roads. The paper went on to refer to rigid tires as used for road steamers, and stated that the amount of adhesion obtained by this tire was much less than by the india-rubber kind. The latter kind took a firm hold of the road, whatever might be the nature of the surface. The only ground upon which india-rubber tires did not work well was where the soil was extremely wet or of a very soft nature. For farm work the wheels of the engine required a much thicker coat of india-rubber.

Mr. Robert Fairlie read a paper On the Gauge of Railways. The author argues for the narrower gauge, and says:- -Experience has shown that 3ft. 6in. can be made a highly economical and efficient width, but it does not by any means follow that it is the most serviceable and most efficient, any more than it follows that the accidental 4ft. 8in. was all that could be desired, even though an Act of Parliament had made it an article of belief. On the contrary, as our knowledge and experience increase, we are enabled to approach more and more nearly to that happy mean on either side of which is error. While, on the one hand, there is every necessity for obtaining such a gauge as will afford a good and useful width of vehicles, on the other it is necessary to avoid such narrow limits as would necessitate the introduction of too great overhang on each side of the rails. The 3ft. gauge appears to me to comply with all the necessary conditions better than any other, and it is from no mere theorising that I lend all the influence I have towards its adoption. There is a certain amount of saving in first cost as compared with the 3ft. 6in., not a large amount, but worth considering. This, however, I leave out of the discussion for the present. The all-important matters are to place upon the rails a thoroughly efficient stock that shall possess a maximum of capacity and a minimum of weight, and to supply engine-power under the most economical circumstances, and I hold it to be easier to accomplish these objects on the 3ft. gauge than upon any other. I am led to this conclusion both by a comparison of the actual work done on the railways of the 3ft. 6in. gauge, with that which can be accomplished with the 3ft. gauge, and because, having in view the practical requirements of goods traffic, I find that I can obtain an ample floor area with less dead weight than can be secured by any other width; on a wider gauge the dead-weight increases, on a narrower one the capacity diminishes. He quoted figures to show that to carry 50 tons of goods on the Norwegian or Queensland 3ft. 6 n. gauge, the proportion of one ton per waggon being preserved, 92 per cent. of the weight of rolling stock used on the 4ft. 8in. would be required; as against only 43 per cent. on a 3ft. gauge, showing a saving of 47 per cent. on the latter as compared with the 3ft. 6in. Of course, if the waggons were loaded up to full capacity, these percentages would be very much changed. It is to this point especially that I wish to direct your attention, as upon it the economy of the 3ft. gauge rests. Whatever saving may be effected in first cost may be lost sight of, the great advantage lying in the saving effected in working expenses. Every ton of dead weight saved goes towards securing the prosperity of the line, and if we can obtain the ample platform which the 3ft. gauge gives, combined with so much saving in weight, nothing is left to be desired.

A paper On a New System of Warming and Ventilation by Mr. J. D. Morrison, was read. The main features of the syslem consist in so circulating fresh air through a warming champer into the room, and foul air through the fire into the chimney, :hat all local currents are resolved into one, which forms an upper warmer current from the fire to the opposite wall, and an under colder current from the wall back again to the fire, when, after supporting combustion, the products escape up the chimney. The vacuum thus produced by the warmer current through the chimney creates the now colder current from the atmosphere, which, passing through the heating chamber, supports the respiration of any number of persons.

On Friday, August 8, Mr. A. E. Fletcher, F.C.S., read a paper On the Rhysimeter, an instrument for indicating the velocity of flowing liquids, and for measuring the speed of ships through the water. The principle on which it is constructed resembles that of the anemometer, recently brought into notice by Mr. Fletcher, by which he is able to measure the speed of hot air, flame, and smoke, contaminated with dust or corrosive vapours, as met with in furnace flues and factory chimneys. Both in the anemometer and in the rhysimeter, the impact force of the current, and also its tendency to induce a current parallel with itself, are measured and made to become indicators of the force and velocity of the stream. The apparatus is very simple. A compound tube with two orifices at the bottom, one of which faces the source of the current, while the other faces the opposi'e direction, is held in the stream, and communicates by tubes with the indicator where the pressure is measured by columns of ether, water, or mercury, according to the circumstances of the case. When used to measure the velocity of a brook or open stream of water, the speed at any depth or at any portion of its surface can be separately estimated. For taking the speed of water in pipes it is only necessary that there should be suitable cocks screwed into the pipes at the required places; through these the "speedtube" of the rhysimeter passes without allowing any escape of water, whatever may be the pressure. A still more important application of the instrument is to measuring the speed of ships. Here the speed-tube pierces the bottom or si e of the ship, and projects a few inches into the water outside. The indicator may be in the captain's cabin. It resembles in size and appearance a barometer, In it a column of mercury indicates continually the speed of the ship. The full effect of the velocity is imparted t> the mercury, without loss by friction or otherwise, so that the indication must always be absolutely correct. The instrument may be made self-registering, showing by a dial the total number of knots the ship has run since she left port, and marking on a sheet of paper the speed attained at every portion of the time. This permanent register may, in many cases, be of the greatest value. The paper was illustrated by diagrams, and by tables showing the velocities in knots per hour, or in feet per second, for the various heights of the columns of water or mercury.

Ádmiral Sir Edward Belcher said the principle was very valu able, but he did not see the necessity of passing the tube down so far below the water. He thought one or two inches would suffice.

Prof. Rankine said the principle of the instrument was an old one, and the author, he believed, admitted this. Mr. Fletcher had overcome a series of inconvenient and difficult details, and had produced an instrument which had actually been applied to practice with satisfactory results. He belived that the instrument would be a good substitute for the old log system of ascertaining the speed of a ship.

This section did not sit on Saturday.

SCIENTIFIC SERIALS

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THE article in the Quarterly Journal of Science for July which will be most read, is by the editor, Mr. Crookes, Experimental Investigation of a New Force," on which we have already commented. "The Dawn of Light Printing" gives a sketch of the early discoveries in photography of Niepce, Fox Talbot, and Daguerre. Mr. F. C. Danvers gives an account of the present condition of inventions for Pneumatic Transmission, with mathematical formulæ for the power obtained. Under the title "Where are the bones of the Men who made the unpolished Flint Implements?" Mr. Pengelly argues that we know so little about the effect of various climatic and atmospheric conditions on the bones of man and the lower animals, that it is rash to con

clude, because human remains are not, as a rule, found associated with fliot implements and animal remains in the bone caves, that therefore they cannot have been originally deposited along with them. He also cites a number of unquestioned

instances in which the bones of man have been found in such situations, to all appearance contemporaneous with the animal remains. Even were such evidence entirely wanting. Mr. Pengelly considers the flint implements themselves absolutely conclusive proof of the contemporaneity of man with the mammoth and the extinct cave-animals. One of the most valuable and interesting art cles in the number, though a short one, is entitled "A New Mechanical Agent: A Jet of Sand." Mr. B. C. Tilghman, of Philadelphia, appears to have solved the problem of cutting or carving, mechanically, hard substances, such as stone, glass, or hard metals, in an expeditious, accurate, and economical manner. He has shown that a jet of quartz sand

thrown against a block of solid corundun will bore a hole through

it one and a half inches in diameter and one and a half inches deep in twen y-five minutes and this with a velocity obtainab'e by the use of steam as a propelling power at a pressure of 300lbs. per square inch. The apparatus used for grinding or cuting glass or stone is described in detail. By covering parts of the glass surface by a stencil or pattern of any tough or elastic material, such as paper, lace, caoutchouc, or oil paint, designs of any kind may be engraved upon i. In his abs'racts of the Progress of Science, the editor now confines himself entirely to the physical branches.

THE American Naturalist for August contains no one very striking paper, though several of considerable interest. Dr. J. S. Billin's contributes a mycological paper on the "Study of Minute Fungi," and Mr. A. S. Ritchie one, entitled "The Toad as an Entomologist," showing the very large number of insects which that animal destroys. On one occasion the writer found thirteen perfect insects in the stomach of a toad belonging to nine species, besides one elytron each of two others, and other vestiges of legs and wings. He concludes that the toad is of great service to agriculturists.-Prof. Lesquereux has an article on the "Mode of Preservation of Vegetable Remains in the American Coal Measures," an important article on vegetable palæontology; and Alexander Agassiz a short paper on "Systematic Zoology and Nomenclature," indicating the great importance of a correct system of nomenclature as an item in the history of zoology.

THE Western Chronicle of Science for July 1871. Edited by J. H. Collins, F.G.S. Nos. 1-7. Falmouth, W. Tregaskis. We have much pleasure in noticing the first seven numbers of this local scientific periodical, and sincerely hope it will not be allowed to drop from want of subscribers, of which the editor complains. It should be encouraged by all lovers of scientific inquiry, not only in the western district but throughout the country. Its low price, only twopence, puts it within the reach of all, while at the same time a large circulation is required to make it pay. The seventh number contains an interesting paper, valuable both to architects and geologists, on the ornamental rocks of Devon and Cornwall, counties abounding in beds of vari-coloured limestone sufficiently hard to receive the polish of marble. The second is a most sensible and judicious paper on the duties of local societies. If the suggestions here made were carried out in all societies, an interest in physical science would soon become universal. Besides other matters, the number contains the results of the May examinations in science, so far as these concern, the classes in the We t ot Cornwall. A large proportion seem to have passed in the various subjects, the total number of successful candidates being 69.

SINCE the commencement of the Revue Scientifique, it has continued much the same course as its predecessor the Revue des Cours Scientifiques. Seven numbers are now before us, containing among others, the following articles, besides reports of lectures or extracts from the proceedings of various learned societies at home and abroad-Van Beneden on Commensalism in the animal kingdom, Ancient Churches by M. Ch. Contejean, Geographical distribution of the Balænæ by Van Beneden, Physico-chemical researches or Aquatic Articulates by M. Felix Plateau, M. Chauveau's Report on Science and Legislation in relation to the Cattle-plague in France, M. Claude Bernard on the Influence of External Heat on Animals, Accounts of the Life and Writings of M. Claparède and Prof. Payen, M. Pasteur's address, "Why France did not find superior men in the moment of peril," the addresses delivered at the Liverpool meetings of the British Association by Huxley, Tyndall, and Rankine, and repo ts of some of the sectional proceedings.

SOCIETIES AND ACADEMIES

BENGAL

Asiatic Society, June 7.-"Memorandum on the Total Eclipse of December 11 and 12, 1871," by Lieut. -Col. J. F. Tennant, R. E., F.R.S. In December of this year we have a Total Eclipse visible in Southern India. The duration is short, but in some respects the circumstances are very favourable, as the Line of central Eclipse passes over the Nilgherry Hills, where, I understand, fine weather may be confidentle expected. In order to be prepared, I have computed carefully the Central Line across India, and have added the extent to which errors of the Tabular place of the moon may be expected to shift it. I hope to have before the Eclipse a knowledge of what errors may be anticipated in the Tables, and thus be in a position to choo-e a central spot, if it is worth making a change. The figures, however, show that this is not probable, the principal result of an error in Right Ascension being to shift the centre of the shadow along its path, the deviation from which would be corrected by a small error in the declination which could hardly be foreseen. The duration of the Eclipse will be small. At the Nilgherries it will be about two minutes, but this cannot, so far as I know, be as yet accurately predicted, from uncertainty as to the real diameters of the sun and moon, when free from the enlargement by irradiation. If the value of the moon's diameter deduced by Oudemans from Eclipses, be used with that of the sun obtained in the Greenwich Transit Circle, then I find the duration in the Nilgherries just two minutes. The data of the Nautical Almanac give two minutes seven seconds, and if I may judge from the result I got in 1868 the real duration will fall between these. Short as this time is, it is enough with an adequate preparation to produce some results of value. It is long enough to allow photographs to be taken of the Corona, as to whose structure there is more to be discovered. There seems now no sort of doubt that the Corona is not only a solar appendage, but is, as I stated in my report on the Eclipse of 1868, the comparatively cold atmosphere of the

sun.

This should be further spectrosc pically examined. Observers have differed about the number and position of the faint bright lines they have seen, but it does not seem that any one has connected the variations with the position of the part examined. To do this appears urgently necessary, and there have been additions made to the spectroscope which will allow more than one portion of the Corona to be examined, and its lines recorded during the short time it is visible. There is ano her subject, too, of spectroscopic examination. Kirchhoff, in his theory of the solar cons'itution, supposed it surrounded by an extensive atmo-phere consisting of metallic and other vapours, as well as gases, by the absorption of which the dark Fraunhöfer lines were produced. It has long been clear that there was no such extensive a mosphere, and s me physicists have been satisfied that there is none such. Mr. Lockyer and his collaborateurs, though they have detected a great number of bright lines at the bases of the prominences, have never approached, so far as I know, the number of even the conspicuous dark lines, whose origin has, therefore, not been satisfactorily made out. At the Eclipse of December 22, 1870, however, Prof. Young, at the moment of obscuration, and for one or two seconds later, Saw, as far as he could judge, every atmospheric line reversed, and this was confirmed by Mr. Pye. I have but the scant information of this point given in the Royal Astronom cal Society's Council Report, but it is sufficient to show me why this has not been seen before by observers looking out for it, and also to make me feel the importance of verifying the observation. To understand why it has not been seen before, it must be c. nsidered that the image of a bright object in the focus of a telescope when relieved against comparative darkness is enlarged by a phenomenon known as irradiation; the light encroaches on the darkness. The sun thus appears larger and the moon smaller than the real size. This continues till the real contact of the limbs internally; at this moment the thread of light, which previously had considerable width, appears suddenly broken and vanishes in a total ec ipse; while in the transit of a planet or annular eclipse there appears the "black drop" of the observers of the Trausit of Venus in 1769. At page 16, vol. xxix, of the monthly notices of the Astronomical Society will be found some figures illustrating this phenomenon in a planetary trans t. When we are dealing with so thin a stratum surrounding the true photosphere, we cannot see it in sunshine, as it is lost in the irradiation (t may be partly visible in very large telescopes where the irradiation s very small), and we are very ap to lose it a the moment when the sun disappears, for it is found only between the places where

a moment before the sun and moon's limb appeared, so that the observer following either of them might well miss it. In the search for and verification of this important observation, the duration of total phase can matter little. I have been in communication with the Home Secretary on the subject of obser vations of this eclipse, and my views, I may say, have been most cordially receivd. I am not yet in a position to submit a proposition officially, but I have great hopes of being able to do so in a few days. I may just mention that in plotting the shadow track on a map it is necessary to allow for the error of its zero of longitude, a precaution often forgotten. The longitudes of the G. T. Survey require a correction of 3'-2'7", and those of the Atlas of India one of 4-11" to adjust them to the accepted longitude of Madras.

The President was very glad to learn from Colonel Tennant that the Government is likely to sanction a scientific expedition to the Nilgherries on the occasion of the total eclipse in December next. The objects to which Colonel Tennant proposed to direct observation were, he need hardly say, of very great scientific interest and importance. The spectroscop c analysis of the Corona, so far as it had yet been effected, had been productive of no very certain results. The mater could not, however, be in better hands than those of Colonel Tennant. He only wished to suggest that those members of the Society, who might have the requisite leisure and opportunity, should, even with the unaided eye, endeavour to observe as carefully as pos sible the exact apparent shape and characteristics of the Corona. He believed that data of very considerable value might be thus obtained by persons who knew how to observe. Later in the evening Colonel Tennant kindly consented to draw up some short direct ons which might serve as a guide to members of the Society who might visit localities of the total eclipse.

PARIS

Academie des Sciences, Aug 7.-M. Faye in the chair. Notice was given of the death o. M. Lecocq, a correspondent living in Clermont Ferrand, the author of valuable pamphlets and papers on the geo ogy of Central France. M. Lecocq was, however, a very active and clever physicist, and started many theories of his own. He was a Professor in the University, and his loss will be very deeply felt by his friends.-Two different papers were sent describing a bolide which was seen on the 15th of August, and which is most extraordinary, as it was visible during twenty minutes by Marseilles observers. The course was most irregular and zig zag. Leverrier supposed that two different bolides might have been seen at Marseilles and at the other stations, as the descriptions do not agree. The fact of remaining visible during so long a time at Marseilles is astonishing, and M. Leverrier is at a loss to account for it. The phenomenon will be more fully investigated. This is also the case with a paper sent by M. W. de Fonvielle, describing the fall of a thunder-bolt on August 3, 3h 19m, on the kitchen of a convent situated in Paris, at 250 yards from the National Observatory, where the astronomers felt a great

shock.

A gas-burner was lit under very curious circumstances. The explosion was very long and very strong, and it is supposed the lightning was shaped like a sphere falling from the clouds, M. Dumas showed the interest of elucidating a phenomenon of so much importance for public safety, as ignition of gas may be the Dumas and M. Jamin, professor to the Sorbonne. Special secret cause of many fires. The committee is composed of M. experiments and inquiries will be made at the expense of the Academy. M. Fonvielle will be an auxiliary member of the during his administrati n, and showing that observations of small committee.-M. Delaunay read a paper on the Observatory planets will be made with greater zeal than on former years.—A letter was read from M. Angström, the Swedish physicist, maintaining that each gas has its own spectrum in spite of the differences exhibited by previous experiments. The learned physicist shows that in each case where differences were found, it is possible to explain it by extraneous matters, mixed with the substance submitted to the experiment. The importance of this memoir is obvious.-M. Bert, who was formerly the Prefect of the North during the investment of Paris, sent a paper on the death of fishes living in fresh water when immersed in sea water. fishes are literally suffocated by a singular effect of desiccation, with large scales. The phenomenon is quite extraordinary when the exosmose is very active, princ pally when their skin is clothe observed on frogs, which lose the greater part of their weight, and are almost as much dried up as if they had been salted ve

This has since been lone.

These

M. Bert will examine the action of fresh water on sea-fish, which is not so rapid. These sea-fish are too heavy for fresh running water, and are found generally to remain at the bottom of the water. On the contrary, fresh water fish always swim at the top of salt water.

NEW YORK

Lyceum of Natural History, Oct. 24, 1870.-In a paper read at this sitting the author observed:-In the sequence of events included in our Drift period there is a marked break, a middle period, during which, over most of the north-western states, no Drift deposits were made, and when most of this area was covered with a forest growth and sustained many and large animals. At a subsequent period, all parts of this area, less than 500 feet above the highest of our present great lakes, was submerged, and most portions of it covered to greater or less depth, with new Drift deposits, clays, sands, gravel and boulders, a large part of northern and remote origin. Nearly all the large boulders of the Drift belonging to this later epoch are sometimes of great size (100 tons) and have been floated to their present positions, as they overlie undisturbed stratified sands and clays, which would have been broken up and carried away by glaciers or currents of water, moving with sufficient velocity to transport these blocks. Hence they must have been floated from the Canadian highlands, the place of origin of most of them, by icebergs. This epoch of the Drift period I have therefore termed the Iceberg Epoch. During this epoch the submergence of the land in the interior of the continent, was greater than in the epoch of the deposition of the Champlain and Erie clays, and all the area north of the Ohio was covered with water up to a height of over 500 feet above Lake Erie, or 1,100 feet above the ocean level. The highlands of south eastern Ohio, and most of the country south of the Ohio river, were not covered by this flood, and now bear no drift deposit of any kind. Tracing out the line of ancient water-surface, we find that the depression was greater towards the north, so that the Alleghanies and their foot-hills, and also a wide area of comparatively low country in the Southern states, formed not only a shore, but a continental limit to the great interior iceberg-ridden sea of the later Drift Epoch. In the western reaches of this sea, which was of fresh water, in the later centuries of its existence, was deposited the Löes or "Bluff" which I have elsewhere designated as the later lacustrine, non-glacial drift. During the deposition of the Löes the interior sea was already narrowing and growing shallower by the cutting down of its outlets, or by continental elevation, or both. The descent of the water-level and decrease of water-surface have been going on perhaps constantly, but not uniformly, to the present time, when the area of the great lakes is the insignificant 85,000 square miles it now is. In the descent of the water-level, retarded at certain periods, terraces and beach lines were formed at various places by the shore waves. With these history ends. This then is the classification I would suggest of the drift deposits as they occur in the valley of the Mississippi, premising that here, as in other geological periods, the column is nowhere absolutely complete :

[blocks in formation]

NOTES.

Sand and gravel beaches with logs, leaves, and fresh-water shells. Lões with fresh-water and sand shells.

Boulders, gravel, sand, and clay, drifted logs, elephant and m stodon teeth and bones.

Soil-peat with mosses, leaves, logs, stumps, branches, and standing trees, mostly red cedar. Elephas, mastodon, castoroides, &c.

Laminated clays with sheets of and gravel, occasional rounded scratched northern boulders, many angular pieces of underlying rocks.

Local beds of boulders and rarely boulder clay resting on the glaciated

surface.

From the above table it will be seen that the remains of elephant, mastodon, and the gigantic beaver, occur in the forestbed and in all the succeeding drift deposits. It should also be said that they are found in still greater abundance in peat-bogs and alluvial deposits which belong to the present epoch. We have seen that the submergence of the later drift epoch, though

so wide spread, left a large part of the area lying between the Mississippi and Atlantic uncovered. This area the elephant, mastodon, great beaver, &c., inhabited during the continuance of the flood that covered the forest bed. From this retreat they issued with the subsidence of the water, following the retreating shore-line, till they occupied all the region now exposed about the great lakes. By what influence they finally became extinct, we cannot yet say. It has been claimed that they continued to exist down to the advent of man, and that he was an agent in their destruction. This statement may be true, but requires further proof before it can be accepted with confidence. The vegetation of the forest bed indicates a cold climate, thus confirming what we had otherwise learned of the habits of the extinct elephant. He was clothed with long hair and wool, was capable of enduring, and probably preferred a subarctic climate, and was associated in this country as in Europe, with the musk ox and the reindeer. We may therefore infer that a progressive increase in the annual temperature, drove most of the animals of the Forest-bed northward, and caused to gather on the shores of the Arctic sea, the herds 'of elephants whose remains so much impress all travellers who visit that region. This was probably the scene of the last vigorous and abundant life, and of the death of the species; an event consequent, perhaps, on the action of local causes, which we shall comprehend when we have opportunities of studying the record. One remarkable statement in regard to the Forest-bed requires notice. In more than one instance, parties digging wells in South-Western Ohio, have reported not only that they found a black soil and logs, but that "some of these logs bore marks of the axe, and were surrounded with chips." These stories I formerly rejected as pure fabrications; but in the light of recent observations, they seem to me to be in part true, and not difficult of explanation.

BOOKS RECEIVED

FOREIGN-Through Williams and Norgate)-Skandinaviens Coleoptera Synoptiskt Bearbetade, vol. x: C. G. Thomson.-Medicinische Abhandlungen: E. Reich.

PAMPHLETS RECEIVED

ENGLISH.-Journal of the Chemical Society, second series, vol. ix The Seat of the Soul Discovered: J. Gillingham (F. Pitman).-Notes on the Antechamber of the Great Pyramid: Capt Tracy, R.A.-Proceedings of the Essex Institute, vols. i. to vi-Bulletin of the Essex Institute from the commencement to August 17, 1870.-Instructions for the Prompt Treatment of Accidents, &c. : A. Smee.-Accident Insurance Company, a Year's Claims, 1870.-Journal of the Iron and Steel Institute, No. 3, vol. ii.-The Manufacture of Russian Sheet Iron: Dr J. Percy (John Murray).

AMERICAN AND COLONIAL -Transactions of the Entomological Society of New South Wales pt. 2, vol. ii.-The Amer can Gaslight Journal -Transactions of the Academy of Natural Sciences of Philadelphia, parts 9 and 10.Proceedings of the Albany Institute, vol. i., part 1.-Memoirs of the Boston Society of Natural History, 1868-69.-Memoirs of the Peabody Academy of Science, vol. i., No. 2.

FOREIGN-Les Mondes, Nos 14 and 16.-Journal de Medicine et de Chirurgie, Nos. 3 to 6, 1871.-Giornale di Sicilia, No. 173 -Rendiconti, vol. iv., No. 14. Astronomische Nachtichten, No. 1856.-L'Institut, No. 1920. -Annals de Chimie et de Physique, vol. xxii., Jan. 1871.-Bulletin Hebdomadaire, 192. La Revue Scientifique. No. 8- Allgemeine Bibliographie, &c., No. 32.-Sitzunsgberichte Gesellschaft der Wissenschaften in Prag, for 1870.-Zu Anatomie der Elephanten Schilderkrote: Dr. A. Fritsch.-Über die Anzietung: Dr. A. von Waltenhofen

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