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I have before pointed out that an avenue directed them, used as a processional road, a via sacra, to to the rising place of a star, if it is erected over watch the rising of the Pleiades. undulating ground, cannot be straight.

I said roughly parallel ; its azimuth is about the now mention another apparent paradox. If two same (N. 82° E. roughly); but the horizon is only about avenues are directed to the rising place of the same 1° high; it was therefore in use before those at star at different times, they cannot be parallel. It is Merrivale; the exact date of use must wait for not a little curious that absence of parallelism has theodolite values of the height of the horizon, but in been used against avenues having had an astro- the meantime we can see from the above estimates nomical use !

that the declination of the Pleiades was about N. 5° 28

30." and the date of use 1950 B.C., that is some 300 years before the solstitial restoration.

Mr. Worth's survey gives another D

R

line of stones which is not shown in the Ordnance survey. It is undoubtedly, I think, an ancient line, although it is not shown in the

Ordnance map, a clear indication of Cromlech ut Circle

the difficulty of discriminating these

on land cumbered with stones in all directions. Its azimuth is N. 24° 25' E., and the height of the horizon 5° 10'. This gives us

Arcturus at the date 1860 B.C., showon Turcle

ing that, as at the Hurlers, Arc

turus was used before the Pleiades. fenolith

Hence a possible astronomical use is evident, while this row, like the others, could have been of no prac.

tical use to anybody. It is interestFig. 18.–Plan, rom the Ordnance Map, showing the avenues, circle and stones at Merrivale, with ing to note that this single row of their azimuths.

stones is older than the double ones;

this seems natural. Both the Ordnance surveyors and Mr. Worth have It is worth while to say a word as to the different shown the want of parallelism of the two avenues, and treatment of the ends of the south avenue now that Mr. Worth has noted the kink in the southern one. it seems probable that it was used to watch the The height of the horizon, as determined from my rising of the Pleiades. At the east end there is what measures, is 3° 18'. The results of these inquiries, archæologists term a blocking stone”; these observassuming the Pleiades to have been observed warn- ations suggest that it was really a sighting stone. At ing May morning, are as follows:

the west end such a stone is absent, but the final Azimuth Authority N. Declina- Date

Wellhpresre

Lark
N. 83:15 E. Worth 6
6 47 47 1710

Down
Worth 7 16 20 1630

wal
82:10 Ordnance
7 32 0 1520

* Down Bam Worth 8 26 o 1420

rington las Ordnance 8 30 0 1400 To simplify matters we may deal with the Ordnance values and neg. lect the small change of direction in

Wellhore the southern avenue. We have, then, the two dates 1580 B.c. and 1420 B.C. for the two avenues. The Samuli

Somn

Stonehenge argument for the Pleiades is earthwork

Stonehenge strengthened by the fact that at

Louzdan Athens the Hecatompedon was

Down

Tamulis oriented to these stars in 1495 B.C.

Curtalt according to Mr. Penrose's deter

Amesbuy mination of the azimuth.

onaburrow Now this is not the first time I

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Tumuli have referred to avenues in these

Nor granton Down notes. The azimuth of one at Stonehenge was used to fix the date at which sun worship went on there. Fig. 19.- Reprint of Ordnance Map showing that the Cursus at Stonehenge is nearly parallel to That avenue, unlike the Dartmoor

the Merrivale Avenue. The azimuth is 82 and not 84' as shown in the figure. ones, was built of earth, and it is not alone. There is another rearly two miles long called stones in the avenue are longer than the rest. This the Cursus. So far, I have found no solstitial worship may help us to determine the true direction of the on Dartmoor, so there are no avenues parallel to the sight-lines in other avenues, and, indeed, I shall one at Stonehenge leading N.E. from the temple. show in the sequel that it affords a criterion which But how about the other? It is roughly parallel to the in some cases is entirely in harmony with other avenues at Merrivale, and I think, therefore, was, like considerations.

NORMAN LOCKYER.

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that solar observatories have been established in many SOLAR AND TERRESTRIAL CHANGES.

countries, and a continuous record of the solar THI HE problem of the relations between sun-spots changes, so far as they are indicated by present

and other solar phenomena and weather has methods of observation, is now possible by combining engaged the attention of men of science for many the data furnished by all the observatories. The work years past. The results of their investigations have of correlating the three classes of observation has, hownot, perhaps, been so satisfactory or conclusive as ever, not yet been commenced in a systematic manner, were at first anticipated, but this, fortunately, has although the necessity is now fully recognised. not diminished the enthusiasm of those interested in

It is now generally, if not universally, admitted the solution of the problem. The ordinary public who that the sun is practically the sole source of the energy were attracted by the apparent simplicity and prob- which maintains the movements of the earth's atmoability of the relations suggested have undoubtedly sphere. It is the centre of a continuous outflow of been disappointed with the results. There has hence radiant energy, a very small portion of which is interbeen a tendency for some time past to depreciate in- cepted and appropriated by the earth, where it is vestigation in this field of science. On the other converted into other forms of energy. The investihand, the experience of the recent droughts and gation of the rate of this flow of energy and its famines in India, Australia, and South Africa has time variations, the analysis of the total energy into directed attention strongly to the probable relation its elements as that of a series of oscillatory movebetween variations of solar activity and the larger ments of different periods and amplitudes or wavevariations of rainfall over the earth's surface. The lengths, and the problem of its distribution in its aqueous vapour precipitated as rain over large land passage through the atmosphere and at the earth's surareas such as India is produced by evaporation over face are each in little more than the initial stages. In distant oceanic areas, and is thence carried to the departments of the investigation, as, for areas of discharge by the larger atmospheric currents, example, the laws of the absorption of the solar These actions are the direct results of the conversion of energy during its passage through the earth's atmosolar energy, and any large variation in the supply sphere, much work has been done, but with comof that energy must be accompanied with, and paratively little result. followed by, corresponding changes in the amount The appropriation of solar energy by the earth of evaporation and atmospheric movement, and affects it mainly in two ways, first, as a whole, hence, ‘also, of amount and distribution of rain. determining or modifying its magnetic condition, and The determination of the relations thus indicated is secondly, partially, affecting the atmosphere and a not merely of value from the scientific standpoint, but thin surface layer of the solid or liquid mass. Any has important practical bearings, as it may lead to a variation in the flow of solar energy, periodic or satisfactory method of long-period weather forecasting irregular, will theoretically give rise to correspond-a question which is largely engaging the attention of ing changes in the earth's magnetic condition and its meteorologists at the present time.

atmospheric movements. The determination of the Three lines of observation (and hence also of in- relations between the three classes of variation is vestigation) carried on at the present time furnish data on the whole the most important problem in this for the solution of the problem. These are the observa- | field of inquiry into the solar energy and its variations tions of terrestrial magnetism, of terrestrial atmo- and effects. spheric meteorology, and of solar phenomena.

The first part of the problem, that is, the relation A large number of magnetic observatories, of the variations of solar energy (as manifested and furnished with the most delicate and sensitive instru- measured by the observable changes in the number ments, provide a continuous record of the changes of and extent of the sun-spots, prominences, &c.) to those the earth's magnetic state by its action on magnetised of the magnetic condition of the earth shown by its needles at the earth's surface.

action on a magnetised needle suitably suspended, is The work of meteorological observation has comparatively simple, as the earth appears to be made great progress during the past twenty-five similarly affected as a whole and throughout its whole years.

It has not only been extended and im- mass. The variations are indicated as clearly and proved, but is carried on much more systematically satisfactorily by an observatory in India or Australia than hitherto. l'nfortunately its record is very im- as at Kew in England. There are undoubtedly local perfect, as it is probably not too much to say that variations which may require to be eliminated in over at least five-sixths of the earth's surface, order to obtain the general variation. It has, howincluding the greater part of the interior of ever, been conclusively established by observations in Asia and Africa, and over the larger oceanic areas different regions that there is a general parallelism and the Polar regions, the amount of observation is between the amount and extent of the magnetic variexceedingly small and of little value for the solution ation or disturbance and the number and magnitude of the problem. There is hence a continuous record of the sun-spots and prominences. The rule is, the of the meteorological changes of the earth's atmo- larger the number of sun-spots the greater the amount sphere over barely one-sixth of its surface. There is, of the magnetic variation and disturbance. The remoreover, no general collection and publication of lation can, however, at the present stage only be the meteorological data in such a form as to give a considered as statistical, as it has not been estabcontinuous history of the larger atmospheric vari- lished for single sun-spots. In other words, the ations and changes in progress over even that sixth observed outburst or sudden appearance of a single part of the earth's surface.

spot or prominence is not invariably accompanied by The third branch of observation, that of solar a terrestrial magnetic disturbance. Various reasons phenomena, has made wonderful progress during the have been given for the failure of parallelism in past fifty years. Previously the telescopic examination detail. Hence all that can be inferred at the present of the sun's surface had disclosed the eleven-vear time is that definite relations (of a statistical kind) periodicity of the sun-spots. Latterly the combination of great importance have been obtained which more of the spectroscopic and telescopic observation of the than justify the continuance of this branch of the sun has revealed the complexity of the changes in pro- inquiry, and make it desirable that the work of gress throughout the depth of its atmosphere, and of terrestrial magnetic observation and investigation, which the sun-spots are only one and a very partial ex- and of comparison with solar phenomena, should be pression. This field of investigation is so promising maintained and if possible extended.

.

Numerous attempts, only very partially successful, perhaps a first approximate solution. This opinion have been made to establish similar definite relations found expression fully at the meeting of the British between solar and terrestrial atmospheric variations. Association at Southport in 1903. Sir Norman The South Kensington observatory has done much Lockyer, director of the Solar Physics Observatory, valuable work in this direction. It is, however, South Kensington, read a report giving a summary doubtful whether the results obtained by any of the of the results of previous investigations in “ Simulinvestigators in this branch are generally accepted. taneous Solar and Terrestrial Changes " to Section 1

The reasons for this very partial success are almost of the British Association. The members of the self-evident, and are due to the complexity of the International Meteorological Committee present at the problems presented by the movements of the atmo- meeting joined in the discussion, and it was decided sphere, more especially as modified by the presence that the time had arrived for joint and concerted of very varying amounts of aqueous vapour, the action. A commission to act as a subcommittee of the result of the processes of evaporation and conden- | International Meteorological Committee was formed sation. The effects of the solar variation on the to discuss meteorological observations from the point earth's atmosphere are, in fact, distributed and mani- of view of their connection with magnetism and solar fested in very varying proportion between the physics. The commission held several meetings at different elements of observation, and the direct effect Cambridge in 1904. during the British Association of a solar variation on one element may be followed week. Several additional members were added to the by an opposite effect due to variation of another commission, which now includes the names of the leadelement, so that the final result may be opposite in ing authorities in the three associated branches of character to the initial effect. Thus an increase of science. solar radiant energy would, if there were no increase The chief work of the commission at Cambridge of aqueous vapour amount, cloud or air movement, was to lay down principles for the selection of the undoubtedly increase pressure and temperature. If data required for comparison, and to arrange for the these changes, however, give rise to increased vertical choice of stations and observatories from which it and horizontal movement, it is possible that as a

would be desirable to obtain data prior to entering later result pressure probably, and temperature into communication with the various organisations possibly, might both be decreased below their original that it would be necessary to ask for assistance in or normal level, and hence that the observed change the collection of data. might be the opposite to that of the direct effect of It has been arranged that a meeting of the comthe original variation. Also there is another source mission shall be held in connection with the meeting of difficulty in this branch of the inquiry, due to the of the International Meteorological Committee at fact that in the case of some of the elements of Innsbruck in September. A number of important observation a positive variation over a considerable matters will there be considered. Amongst these are area of the earth's surface must necessarily be accom- the final selection of magnetic and meteorological panied with a negative variation of corresponding observatories from which data are to be collected, the amount in some other region as part and parcel of mode of publication of the data received by the comthe total change. The changes in these elements, mission, and probably, also, of the methods to be taken over the earth's surface, must either be com-employed in the work of comparison and discussion pletely compensatory, as is probably the case for of the data. Hofrath Prof. Julius Hann has pressure, partially compensatory,

is suggested for consideration a method of determining doubtedly the case for rainfall.

the variation of temperature during a sun-spot period. It is also necessary to bear in mind that the instru- This will, it is hoped, lead to an interesting dis. mental appliances for magnetical and meteorological cussion on the methods of investigation most suited observations are of very different orders of exact- and appropriate for the determination of the relations ness. Magnetic instruments, more especially those between solar and terrestrial phenomena. for continuous autographic registration, are of great delicacy. Meteorological instruments are, the other hand, much less delicate, and the most important of all from certain points of view, viz. the

THE PROPOSED COLLEGE OF APPLIED instruments for registering the direction and rate

SCIENCE. of diair movement, are especially coarseife and their T HE appearance of the preliminary report coflebe large errors.

of Science and Royal School of Mines, which was pub. The problem of the relations between solar and lished in our issue of last week, brings us an important terrestrial meteorological variations is hence com- step nearer the realisation of an object after which plicated and difficult. It evidently requires for its men of science have long striven; the provision, that complete solution the collection and coordination of is, of a great metropolitan college-liberally endowed, data for the whole of the earth's surface, and the handsomely housed, adequately equipped, and genercareful employment of statistical methods regulated ously staffed-designed amply to supply that higher by thorough knowledge of the physics of the atmo- technical instruction for which there has been little sphere.

provision hitherto, but upon which our well-being as a a The difficulties of the problem are great, and commercial and manufacturing nation ultimately explain the comparative want of success of investi- depends. gators hitherto. It is, however, certain from The report shows that the committee has been en. theoretical considerations that there are definite re- gaged wisely in determining what precisely the existlations, and that their determination is of great ing facilities for instruction in applied science are, and importance, equally from the scientific and the in gathering the information necessary to decide what utilitarian point of view.

the new college should supply in addition to these, The observational data for

systematic so as to place London, as the centre of the Empire, investigation are now considered by many to be in a condition to compare educationally with Berlin, sufficient, if collected, compared, and discussed as a for example, or with many great American cities. It whole, to promise more satisfactory and valid con- is unnecessary here to recapitulate the recommendaclusions than have hitherto been obtained, and tions of the committee, but the special wisdom of

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one or two of its conclusions cannot be insisted upon | long have at South Kensington a college of applied too earnestly or too often,

science which will be as much admired as the similar The new institution must be in no sense parochial, institution at Charlottenburg, and prove as useful to nor must it be allowed to become merely metro- the industries of this country as the Berlin college has politan. From the beginning the design must be to to those of Germany. give the college an Imperial character, and every means must be taken to encourage young men pos

NOTES. sessed of the necessary qualifications, in whatever part of the Empire they may be, to attend its courses As the new buildings of the University of Sheffield and avail themselves of the means offered by it of were opened by the King at the time the present issue becoming familiar with recent advances in technology of Nature was being prepared for press, we cannot do and with any branch of applied science in its highest more than record the fact, reserving a description of the form.

The new institution must not be allowed to become buildings and an account of the opening ceremony for a merely another technical college on a larger scale of subsequent number. technical institutes we have many already. The “duly The annual meeting of the Imperial Cancer Research qualified students " referred to by the committee

Fund was held on July 5 at Marlborough House, the should have already received collegiate training, and have taken a degree. To quote the report :

Prince of Wales presiding. Sir William Church moved ** Admission to these higher courses should be re

the adoption of the secretary's, superintendent's, and stricted to duly qualified students who, it is hoped, treasurer's reports, which was seconded by Mr. Tweedy. would be attracted from all parts of the Empire. Mr. Henry Morris moved that the best thanks of the The public must be taught to estimate the success meeting be given to His Royal Highness for presiding, of the new institution, not by the number of its which carried with acclamation. The Prince of roll-call, but by the number of expert engineers of Wales in reply alluded to the researches which had been all kinds, of original technical chemists, of machine carried out in the laboratories of the fund, and expressed designers, and so on, who are trained within its his satisfaction that the committee had again secured the portals.

services of Sir William Church chairman of the But besides being able to supply the future manu

executive committee. facturer with the very latest results from the research laboratories of workers outside its walls, the new in- The summer show of the Royal Horticultural Society stitution, if it is to be really successful, must itself be was opened on Tuesday last, and will remain open until this an active centre of research. As the report says :-" It evening. It is being held for the first time in the grounds is of the first importance that there should be no divorce between teaching and research in technology of Chelsea Hospital. The society appears to be in a very on the one hand and in pure science on the other,” and Aourishing condition, more than 1000 new fellows having the new college must be as notable for its success in been added within the last few months. research in technology as for the ability possessed by

The Albert medal of the Society of Arts for 1905 was, its staff to acquaint the student with the findings of recent scientific work. Unless from the beginning

on Wednesday, July 5, at Marlborough House, presented by the student feels he is under the influence of professors the Prince of Wales, as president of the society, to Lord who are not only familiar with all the conditions of Rayleigh in recognition of the influence which his reactual manufacture in its most successful form, but searches, directed to the increase of scientific knowledge, who are responsible also for the improvements in have had upon industrial progress, by facilitating, amongst technical processes which win success, the institution other scientific applications, the provision of accurate will neither do the work expected of it nor win the electrical standards, the production of improved lenses, and confidence of our manufacturing magnates and mer- the development of apparatus for sound signalling at sea. chant princes. Only that science—whether pure or applied—really lives which grows continually, and The French Association for the Advancement of Science such growth without patient research is impossible. will this year meet at Cherbourg. The session will extend The new institution must above all things be the from August 3 to 10. growing point of our national system of technical instruction.

The summer meeting of the Institution of Naval ArchiTo fulfil these two functions-on which the report

tects will take place on July 19, 20, and 21 in the hall rightly lays very great emphasis—the staff of the of the Society of Arts. The following papers will be Imperial college must be both numerous and the best read and discussed :-“ Tactics and Strategy at the Time available. In other words, the institution must of of Trafalgar," by Admiral Sir Cyprian Bridge, G.C.B. ; necessity be a costly one, judged, that is, from the “ The Ships of the Royal Navy as they Existed at the standard adopted previously in this country for estim, Time of Trafalgar,” by Sir Philip Watts, K.C.B., F.R.S., ating educational expenses. But if properly selected vice-president ; " The Classification of Merchant Shipping, plished, that generous expenditure on higher educa- illustrated by a Short History of Lloyd's Register," by tion is a remunerative form of national expenditure. H. J. Cornish; “ Experiments with Models of Constant It is gratifying to find from the report that there is Length and Form of Cross Sections, but with varying every prospect that a sufficient revenue will be eventu- Breadths and Draughts,” by Lieut.-Col. B. Rota ; “ Exally forthcoming, in the provision of which funds the periments on the Effect of Depth of Water on Speed, State will take its part. We learn from the Times having Special Reference to Destroyers recently Built,' that the Government has decided to allocate 20,000l, a by H. Yarrow; “ Deductions from Recent and Former vear to the college out of the Treasury subsidy for the

Experiments on the Influence of the Depth of Water on maintenance of the Royal College of Science and the Speed," by W. W. Marriner ; “ The Failure of some large Royal School of Mines, and that an intimation to this efíect has been made by the Chancellor of the Ex

Boiler Plates," by J. T. Milton; and “A Comparison of chequer to Mr. Haldane, the chairman of the Depart. the Performances of Turbines and Reciprocating Engines mental Committee.

in the Midland Railway Company's Steamers," by W. There is every reason to hope that London will ere Gray.

The London congress of the Royal Institute of Public years, visiting England, Ireland, North America, Central Health will be held from Wednesday next, July 19, to America, and Colombia. Returning to his native country Tuesday, July 25, under the presidency of Sir James in 1857, he contributed numerous articles on his travels Crichton Browne. The meetings will take place at King's to periodical literature, and published a small volume College, Strand, and at the Polytechnic, Regent Street. entitled "

Voyage à la Sierra Nevada de Sainte Marthe." In connection with the congress there will be an exhibition Later he wrote two books dealing respectively with the of sanitary and educational appliances at the Regent Street

earth and the ocean. He began at Clarens, on the Lake Polytechnic, and this will remain open until July 28. of Geneva, the work of his life—the “ Nouvelle Géographie

Universelle," the first volume of which appeared in 1876. The British Medical Journal announces that a tuber- The work was issued in parts, and was completed in 1894. culosis exhibition, arranged under the auspices of the

the whole occupying nineteen volumes. On the conclusion National Association for the Study and Prevention of

of this great task Reclus began another work dealing Tuberculosis, and of the Committee on the Prevention of

with the historical side of human development, i.e. with Tuberculosis of the Charity Organisation Society, will be held in New York in November next.

history as influenced by geographical conditions. He left The object of the

this book, it is said, in a complete state, ready for exhibition is the education of the people. In addition to

publication. exhibits illustrating different phases of the tuberculosis problem, and especially the treatment of the disease,

The death of Prof. Hermann Northnagel, of Vienna, popular lectures will be delivered by specialists.

in his sixty-fifth year, is announced. He made many The Long Fox memorial lecture for this year will, says

contributions to medical literature, and by these and the Lancet, be delivered in November by Dr. E. Markham

his discoveries in regard to heart action he was well Skerritt.

known in the medical profession. Prof. Northnagel was

a corresponding member of the Royal Medical Society of M. Curie was last week elected a member of the Paris

this country.. Academy of Sciences.

MANY of our readers will be glad to learn that steps The Mary Kingsley medal of the Liverpool School of

are being taken to raise a memorial to the late Prof. Tropical Medicine has been awarded to Dr. Laveran, of

G. B. Howes, F.R.S. In the circular letter on the subject the Pasteur Institute, Sir Patrick Manson, K.C.M.G.,

which has reached us it is pointed out that his death was F.R.S., and Col. Sir D. Bruce, K.C.B., F.R.S.

probably due most of all to overstrain occasioned by his LORD KELVIN AND Sir William CHRISTIE, Astronomer

unsparing zeal in the acquisition of full and accurate Royal, were at the final meeting of the present session

knowledge and the undeviating readiness with which he of the Optical Society made honorary members of the

imparted the fruits of his genius and learning, not only society.

to his regular pupils, but to every association which asked

for his assistance. It is proposed that the memorial shall It is stated in Science that Prof. William Osler has take the form of an endowment fund for his widow and been made honorary professor of medicine at the Johns daughter. Subscriptions should be sent as soon as possible Hopkins University.

to the honorary treasurer, Mr. Frank Crisp, 17 Throg. The president of the Board of Agriculture (the Right

morton Avenue, E.C., marked on the cover ' Howes Hon. Ailwyn E. Fellowes) will distribute the diplomas and

Memorial Fund." We trust there will be a generous prizes at the South-eastern Agricultural College, Wye, on

response to the appeal. Friday, July 21.

A MEETING of members of the Essex Field Club took We learn from the Royal Society that as an adjunct to

place, by invitation of Lady Warwick, at Easton Lodge the International Laboratory of Physiology on Monte Rosa,

on Saturday last to inaugurate a photographic and pica lower laboratory, with a hostel, has been established

torial survey and record of Essex. The object of the at Col d'Olen. This lower laboratory is mainly intended

scheme is to make a permanent collection of photographs for biological research, but it is understood that provision

and other pictures of objects of interest, also maps, plans, has also been made for the study of terrestrial physics

and other documents, in order to give a comprehensive and meteorology. The Royal Society has the permanent

survey and record of all that is valuable and representative nomination to two posts, each of which includes a living placed on view in the museum of the Essex Field Club at

of Essex. The pictures, plans, &c., will be deposited and room in the hostel, a bench in the laboratory, and the use of apparatus; but the expenses of living and of special

West Ham, and it is hoped that all the photographic researches must be borne by the investigators. The labor

societies and unattached photographers of the country will atory is especially connected with the University of Turin,

assist the committee in its work that its object may but is under the immediate direction of a committee.

be attained. Applications for nominations to the two posts referred to We are indebted to a correspondent for a copy of a above may be addressed to the secretaries of the Royal supplement to the Selangor Government Gasette, dated Society, Burlington House, London, W.

April 28, containing a report from the district surgeon A REUTER telegram from Florence states that the in

of Klang on the progress of anti-malarial measures struments of the Delle Quercie Observatory of that place

carried out at Klang and Port Swettenham," in the recorded on Sunday last severe earthquake shocks

Federated Malay States, during the past four years, from taking place in a distant country.

which we learn that in 1901 malaria was very prevalent

both at Klang and Port Swettenham, there being much The death is announced from Belgium of M. Elisée swampy ground in which, as well as in wells, ditches, Reclus, the French geographer, in his seventy-sixth year. and pools, Anopheles were found breeding. Active work At the University of Berlin he studied under the great was undertaken in the shape of tree felling, the clearing geographer Karl Ritter. Having in 1851, because of his of undergrowth, the filling up of abandoned drains, the political opinions, to leave France, he travelled for six inauguration of a system of drains to carry oft and prevent

as

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