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THE GREAT TYPHOON IN THE PHILIPPINE parative lull in the wind for three or four minutes, and ISLANDS IN SEPTEMBER, 1905.

then it blew more fiercely than ever, with a rapid chang,

of direction from north-by-west to west, and drove the THE Bulletin of the Manila Observatory for September, ship ashore; in a few minutes the wind shifted to south,

1905, prepared under the direction of the Rev. J. and by midnight the barometer had again risen in Algué, š.p. affords a striking example of the way in 29.61 inches. Immense damage was caused by sea anr which any abnormal features of the weather are completely land, especially at the eastern stations. We reproduce au masked in monthly, or even shorter, mean values. An illustration of the destruction of the observatory inspection of the latter would lead to the conclusion that Legaspi (lat. 13° 9', long. 123° 45'); the sea, which had the month of September was quite normal notwithstanding not risen so high for thirty years, rushed into the town the occurrence of the terrible typhoon on September 25-26, with extraordinary force, some parts being submerged 10 which was probably the most violent of any yet experi- a depth of 2 feet to 5 feet. At many other places not a enced, not even excepting that of November 5, 1882, the single building was left uninjured, and some of the large worst previously on record. We gave a brief note of the trees, which had withstood all previous storms, were storm soon after its occurrence, taken from newspaper re- uprooted. ports, but the following further particulars from a discussion by the Rev. M. S. Mata, S.J., assistant director, may be of interest. The disturbance appears to have originated in long.

THE NEW BUILDINGS OF ARMSTRONG 142° E. and between lat. 11° and 12° N. on September 22,

COLLEGE, NEWCASTLE-ON-TYNE. and its path over the Pacific was approximately from east THE new buildings of Armstrong College, to be opened to west ; it reached the land on the evening of September 25, by the King on Wednesday next, July 11, consist of and swept across the archipelago in a south-easterly to the front wing of the college, together with the large public north-westerly direction, reaching Hainan, in the China hall immediately behind the front. The imposing front Sea, on the evening of September 28. The breadth of the block of buildings, about 100 yards in length, faces nearly was about 100 miles, the centre passing about west, and is on the border of the open space known as the

Castle Leazes. In the middle of the college front, rising to a height of feet,

is the handsome Sir Lowthian Bell tower. The chief entrance is at the base of the tower and gives access to a spacious vesti bule which communicates with the north-east and south-west wings, the principal staircase, and the large public hall to be used for lectures meetings, and examinations.

The front wing consists of four floors. On the ground floor to the north of the entrance are the principal's room, the council room, the staff common room, and a larg common room for men students. To the south of the entrance are the secretary's office, the college oftic with strong room, and the electrical engineering department. This last consists of a lecture room, and . spacious laboratory with wide gallery on one side. On this gallery is the main electrical distribution board, to

which leads are brought from every Fig. 1.- Meteorological Station of Legaspi, after the typhoon of September 25-26, 1905.

part of the building. There is a second laboratory of the same size

in the basement beneath. Our twenty-four miles south of Manila ; the average velocity of side the college, on the basement level, is built a house translation was 13.5 miles an hour. The first indication for storage cells. Over the ground-Noor corridor, 10 of its approach at Manila

the morning of connection with this department, is a large photoSeptember 25, when the barometer registered a notable fall metric room fitted up with suitable appliances for carrof pressure. On the previous day the readings were very ing out tests in a complete manner. Access to this high ; an anticyclone so well defined had rarely been room is obtained from the gallery of the ground-fivir observed the Philippines. On the morning of laboratory. September 26 (at which time telegraphic communication to On the first floor is the library, with a photography the south-eastward was already interrupted) the fall became dark-room adjoining, which is used for lantern-slide and alarming, and continued until 2h. p.m., at which time the other photographic work. Accommodation is also provided minimum (29.21 inches) was reached, the mercury having on this floor for the mathematics, the naval architecture fallen about 0.7 inch since gh. p.m. of the previous even- the literature, and the education departments, with their ing; after a short pause the mercury rose again very several lecture and private rooms. On the second floor rapidly. Between noon and 3h. p.m. the gusts of wind there is provision for the botanical department, consisting attained a rate of about 103 miles an hour. The rainfall of an elementary laboratory, an advanced laboratory, in twenty-four hours amounted to 41 inches, of which a research laboratory, lecture and preparation rooms with 2.3 inches fell between 3h. and 5h. p.m., after the passage dark-room, and the professor's private room, There are of the vortex, the wind changing from east-north-east to also on this floor lecture rooms for philosophy. modern south-east, with rapidly rising barometer.

history, classics, and modern languages, as well as prival The s.s. Pathfinder was overtaken by the storm in San rooms for the several heads of departments in these subBonifacio (lat. 12° 10' N., long. 125° 30' E.), and recorded jects. On the third oor is the zoological department, some notable oscillations of the barometer ; at 8h. a.m. on which contains a large room more than 70 feet long. on September 25 the reading was 29.78 inches, and the half of which, towards the front, is used as a zoological mercury fell rapidly until 7h. 37m. p.m., when the mini- museum, and the other half as an elementary laborator mum of 27.17 inches was registered. There was a and also advanced and research laboratories, lecture room.









and professor's private room. In addition, this department

INTERNATIONAL SCIENCE.1 has the use of the fiat roof over a portion of the floor below. This open space will be utilised for maceration THE pursuit of science has always joined in sympathy und similar purposes. Associated with the zoological de- men of different nationalities, and, even before the partment is the marine laboratory which is about to be day of rapid letter-post and quick travelling, intercourse, Terted at Cullercoats, on the coast just north of Tyne- especially by correspondence, exercised a considerable inmouth (see p. 228).

fluence on scientific activity. Such intercourse was, howThe ventilation of the front wing is provided for by two electrically-driven fans in the tower, which exhaust only quite exceptionally was there any direct attempt to

ever, of a personal and purely stimulating character, and from the rooms on the several floors. The heating is by organise investigations which required a combination of means of steam on the new so-called atmospheric system, workers in different localities. Within the last century, and the lighting is by 240-volt electric lamps, which can however, many problems became urgent which could not either be supplied from the college central station or from be solved without some international agreement, and special the town supply. Electric arc lanterns are provided in organisations came into life which have rendered a service several of the lecture rooms.

the importance of which cannot be exaggerated. The large public hall, in which the chief portion of the At present we are confronted with a new difficulty. pening ceremony is to take place, will accommodate, with International combination has become so necessary, and the gallery at the south-west end, an audience of about organisations have in consequence increased to such an 800.

extent, that they begin to overlap, and there has been The foundation-stone of the new buildings was laid by some danger of mutual interference. Fear has also been Mr. T. G. Gibson, a member of council and the most expressed that any attempt to advance knowledge by an generous supporter of the college, on May 2, 1904, and the organised combination of workers might discourage private

efforts, and therefore do mischief rather than good. It must be acknowledged


this danger exists. The proper function of combination must be clearly separated from that of private enterprise, and some general regulating control is therefore called for. The time seeing ripe for a general review of the situation.

We may distinguish between three types of international organisations. The first aims simply at collecting information, the second is intended

fix fundamental units initiate agreements on matters in which uniformity is desirable, while by the third type of organisation a more direct advance of knowledge is aimed at, and research is carried out according to a combined scheme. Generally, an international associ. ation does not entirely fall within any single one of these divisions, but it is useful to draw the distinction and classify the associations

according to the main object which F16. 1.-Xew front wing (facing west) of Armstrong College, to be opened by the King on July 11.

they are intended to serve. In the centre is the Sir Lowthian Bell tower.

The best example of an organisation formed for the purpose of col

lecting information is furnished by buildings have been erected to the designs and under the the great undertaking initiated by our Royal Society, and supervision of Mr. W. H. Knowles, of Newcastle.

having for its object the systematic cataloguing of the scienThe cost of the new buildings, together with the fittings, tific literature of the world, both according to subjects has been nearly 80,000l. The funds have been provided by and authors. Twenty-nine countries (counting the four public subscription, and since the buildings are intended Australian colonies separately) are actively participating as a memorial to the first Lord Armstrong, one of New- in this work by furnishing slips containing the entries castle's most distinguished citizens and benefactors, the which form the basis of the catalogue. A still larger name of the college was in 1904 changed from the Durham number of countries assist by subscribing to the annual College of Science to Armstrong College in the University volumes. of Durham. The area of the grounds within which the The subjects included in the catalogue are classified college stands is between five and six acres. The present according to seventeen branches of science as follows:buildings occupy about two acres, and more than two acres, A Mathematics G Mineralogy

N Zoology excluding roads, &c., are available for the extensions B Mechanics H Geology

O Ana omy that are being projected. The accompanying photograph C Physics

I Geography P Anthropology shows the front of the college, which forms the west D Chemistry K Palæontology Q Physiology wing.

E Astronomy
L Biology

Ř Bacteriology The number of day students attending the college last F Meteorology M Bo'any session was 539, and in addition about 1100 students Subscribers may either obtain complete sets or any of the attended the evening and special Saturday classes. The separate volumes. The relative popularity of the different college forms an important part of the University of the subjects is illustrated by the following table, which gives North of England. The degrees of Durham in science and in the different columns for each science the volumes letters, and its diplomas in agriculture, engineering, and approximately required by each country. The figures are, mining are open to students of the college. The Warden of course, subject to variations from year to year. The of the University (the Dean of Durham) is the president first column shows the number of complete sets subscribed of Armstrong College, Sir Isambard Owen is the principal,

i Discourse delivered at the Royal Institution on Friday, May 18, by and Mr. F. H. Pruen is the secretary.

Prof. Arthur Schuster, F.R.S.

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CDEFGHJKL M N O P Q R countries send in their slips rather earlier than others, so







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for, in addition to the separate volumes; these presumably The total number up to March, 1906, has increased tu find their way into the university or public libraries.


begins 'Sets

that the time interval covered by the investigations to Russia 14 2 2 11 6 18 15 19 20 20 11 8 38 30 514 8 8

which the table refers is not quite the same fur all France 27 4 51117 4 3 10 7 5 615 13 12 7 31816 Nevertheless, the numbers shown in the table possess » Switzerland. 7

certain interest. I have given in the last two columns Canada 7

the number of journals which different countries take Holland.. 5 1 2 1 3 I 2 1 2 3 1 4 3 3 I 1 2 3

into account, and the ratio of the number of slips to the Greece 2

number of publications. Here again it is difficult to Hungary 4

estimate accurately how much value is to be attachrd to Norway 3 I I

2 4 1 India

the figures, as there is no uniformity of selection as in 29 5 4 7 5 2 5 2 3 4 2 5 14 5 2 4 6

what should and what should not be included in the catan United States 62 11 14 17 14 10 11 8 12 10 7 9 12 10 3 3 7 9 logue. Great Britain 29 5 7 18 17 6 8 8 8 5 4,

Journals which may only very seldom contain 6 6 5 6 6 7.13

any paper which is be included Austria

may unduly 4 T 4 2 I 4 3 5 6 2 4 4 5 1 3 1

diminish the numbers in the last column, which are also Cape of Good Hope 6

affected by the interpretation given as to what is purely 2 2

technical, and therefore to be excluded. Nevertheless, the Denmark 6

comparison between the United Kingdom and France gives Egypt I

the somewhat striking result that, while France is slightly Fioland I 1 2 2 2 1 1 2 3 1

2 2

2 I

ahead in the number of separate entries it contributes to Germany 44 6 8 14 18 2 5 3 4 5 1 13 9

5 2 18 7

the catalogue, it takes account of nearly double the Italy 27

number of journals, and the ratio showing the number Japan.. 15

of entries per journal is therefore very small. Mexico 5

the case of Belgium and Canada, find also a New South

large number of publications as compared with the slips Wales

received. Regard must, however, be had to the fact that Nova Scotia 1

in the subject catalogue the same paper may furnish Orange Riv.

several entries. Especially is this the case in the biological Colony I

subjects, where several species may be described, for Poland

each of which a separate slip must be written out. Hence Portugal

in any country active chiefly in the discovery of new Queensland

species the ratio given in the last column of the table S. Australia

would be abnormally large. This is probably the explanSweden 5

ation of the figures given for New Zealand. In the opinion Victoria I

of the director of the Central Bureau, the standards adopted W, Australia 1

by different countries are drawing nearer together as the

work proceeds, and before long we may therefore expect to Total 315 36 46 86 86 45 55 58 66 59 3965 103 85 32 34 68 64 obtain valuable statistical information on the scientific The popularity of the special botanical catalogue is

activity in different countries. But this is only an in

cidental result of the undertaking. It may reasonably be remarkable. We may obtain a rough idea of the scientific activity begins a research, to trouble too much about what may

argued that the scientific investigator ought not, before he of different countries by comparing the number of slips received from them during a certain interval. The

have been done by others in the same direction, but there

is no doubt that before publication he should have made numbers given in the report published by the International Convention held in London last summer, and referring to

himself acquainted with the literature of his subject. A all slips received, are shown in the following table :

well-arranged catalogue then becomes a necessity, though its value as a means of helping students differs considerable

in different subjects.

Average Slips Number of number of The governing body of the catalogue is an Intrrnational journals slips per Council composed of one representative from each of the


countries taking part in the scheme. This council has

appointed an executive committee, of which Prof. Army Austria



25 strong is the chairman. Belgium



The Central Bureau for the publication of the catalogue Canada


is in London, under the direction of Dr. Henry Forster Denmark



Morley, who has a staff of thirteen workers under him, Finland



There are, in addition, nineteen experts or referees reFrance 60,401 930

presenting the different sciences. The annual office expenses, Germany

213.545 1,397 153 including salaries, amount to about 22001. ; while the exHolland


70 141 penditure on printing, binding, and publication in the year Hungary

2,605 35

75 ending March 1, 1905, amounted to nearly 49001. The two India and Ceylon



87 items are just covered by the guarantees of the different Italy

21,238 300

71 countries, which, as already mentioned, take the form of Japan


72 subscriptions for copies of the catalogue, so that it may be New South Wales



said that the central office is self-supporting. After New Zealand 440

short a time of working, this success must be a source of Norway


considerable satisfaction to Prof. Armstrong and those who Poland 5,830 65

have helped to initiate the work ; but the expenses incurred Russia

25 741 457


in London only represent a fraction of the total cost of the South Africa



125 work. Most of the countries establish regional bureaui, South Australia


26 which prepare the slips and forward them to London. Sweden



31 This really constitutes the most serious part of the work Swiizerland

5,140 126

41 In Germany, for instance, the Regional Bureau is under United Kingdom


116 the direction of Prof. Uhlworm, .one of the university United States of America


librarians, who is helped by six assistants, and devotes tris Victoria (Australia)


I 24

whole time to the work.

I pass on to an undertaking of a very different kind, but Total... 504 297

still one which must be included in the class whik 90

primarily aims at cataloguing. The accurate determination



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of the positions of the stars for a particular period is a I now pass on to those undertakings which are intended work which must precede all exact investigations of their to fix standards of measurement, or to establish a general proper motions. Hence it constitutes a fundamental

agreement on matters in which uniformity is desirable. problem of astronomy. The multitude of stars seen The foremost place in this division must be given to the bright night is bewildering to the casual observer. They Bureau International des Poids et Mesures, which was are described in poetical writings as innumerable, but when established in the year 1873 at Sèvres, near Paris. This an actual count is made, it is found that their number is bureau was the outcome of an International Commission really moderate, and it is doubtful if more than two constituted in 1869, which had for its object the scientific thousand stars have ever been visible to the naked eye construction of a series of international metric standards. at the same time. The use of the telescope consider- By a convention entered into by the different countries at ably increases this number, according to the size of a diplomatic conference held at Paris in March and April, the object-glass or reflecting mirror used. Thus Argelander 1875, means were created for carrying out the work of in his great star catalogue included nearly 324,200 stars verifying standards under a new International Metric Comwhich he observed through his telescope of four inches mittee, and for the purpose of enabling the committee to aperture.

The advent of photography and the manu- execute its duties effectually, as well as of securing the facture of suitable lenses to be used in connection with future custody and preservation of new metric prototypes photography increased the astronomical output of a fine and instruments, the Permanent Metric Bureau right to such extent that it became possible to founded. The original cost of the bureau was 20,000l., make a further and very substantial advance. The Inter- and the annual budget was fixed at goool, for the period national Star Catalogue which is at present being con- during which the prototypes were being prepared, after structed owes its origin chiefly to the hard work of which time it was expected that the expenditure could be Admiral Mouchez, who was at the time director of the reduced to 2000l. In 1901, however, it reached 40001., Paris Observatory, and who became converted to the the maximum to which, by the terms of the convention, feasibility of the plan by the excellent results obtained the annual budget could be raised. Great Britain did not by the Brothers Henry, the pioneers in star photography. join the convention until 1884, when it declared its He was assisted by the energetic support of Sir David adhesion. A first payment of 17871. was made as entrance Gill, to whom the first suggestion was due. The pro

fee, and the annual contribution now ranges between 2001. gramme of work was determined upon at an International and 300l. Major MacMahon, to whom I owe the above Conterence which met at Paris in the year 1887. Eighteen details, is at present the British representative on the observatories were to take part in the work, the telescopes International Committee. to be used were to have an aperture of thirteen inches, and

The work carried out at Sèvres is not confined to the such a focal length that a millimetre on the plate corre- reproduction of metric standards, but measurements of presponded to one minute of arc. Each observatory had a

cision in various directions have been made with contprtain region of the sky assigned to it, and undertook to spicuous success. Scientific thermometry owes much to cover this region four times, twice with plates of short

the International Bureau, and in some respects it may be pxposure, twice with plates of long exposure, and said that exact thermometry was created there. Prof. Pasure all the stars appearing on the short-exposure photo- Michelson's work, in which the length of the metre was graphs. The long exposures were intended for reproduc- compared directly with the length of a wave of red light, tion in the form of charts, and are only taken by some

is another classical investigation carried on in the laborof the observatories. As there are about 400 stars on each

atories of the International Bureau. More recently Mr. plate, and it takes about 600 plates to cover the share of | Guillaume examined the physical properties of alloys,

ne observatory once, this means that each observatory notably those of nickel steel, and proved the possibility has to measure nearly half a million star places, and that of manufacturing a material which shows no sensible the complete catalogue will give the positions of nearly expansion with rise of temperature. The importance of 41 million stars. This includes all stars down to the metallic rods the length of which does not depend on eleventh magnitude.

temperature is obvious, provided they prove to be of The following is a list of observatories taking part in

sufficient permanence. the work :-For the northern hemisphere, Greenwich,

Time does not allow me to give an account of the conOxford, Paris, Bordeaux, Toulouse, Potsdam, Helsingfors,

ference and conventions which have led to a general agreeRome, Catania, Algiers. For the southern hemisphere,

ment on the standards of electric measurements, but it is San Fernando, Tacubaya, Santiago de Chile, Cordoba,

a satisfaction to know that these standards are essentially Cape of Good Hope, Perth (W. Australia), Sydney,

those proposed and first constructed by the British AssociVelbourne.

ation. The old British Association ohm no doubt was The work connected with the ultimate completion of the found to be wrong by more than i per cent., but it has Catalogue, and especially the reproduction of the star maps,

remained the prototype of the present international unit, feuuires a considerable expenditure. Each country has to

and in principle the old ohm, volt, and unit of current take its own arrangements, which in the British Empire Stand as they were given to us by the original committee." usually means that each body concerned has to pay its own

While in the case of scientific units complete agreement There was, however, in this case some official is absolutely essential, uniformity is desirable in other cases. trip. The Astronomer Royal obtained a contribution of

There are matters of nomenclature in which confusion nl. from the Government for the reproduction of charts,

has arisen purely from want of general agreement. Thus ind in the case of the Cape of Good Hope the necessary

the great recent improvement in the optical power of "panses have been met from Imperial funds. Prof. Turner,

telescopes has led to the discovery of many details on the of Oxford, has obtained a grant of 1000l. from the Govern

surface of the moon. Small craters or other distinctive tient grant of the Roval Society, and a further sum of

features named by one observer were not correctly identified 26wwd for publication from the Treasury and the University by another, so that at the present time the same name is it Otford jointly; but the Australian colonies are much applied to quite different things by different observers. It hampired by the want of funds, and their work will be is quite clear that an international agreement in lunar Irlased in consequence. The four French observatories, nomenclature is called for. on the other hand, are well supported. Each of them has There are other deficiencies of uniformity which erhaps ravived a Government contribution of 25,700l., making a

appear trivial, but which yet lead to the waste of a good 100,000l. More than half this goes deal of time. Such, for instance, is the position of the index towards the reproductions of the long-exposure photographs in scientific books. The index is placed sometimes at the as a series of charts, which, however, have proved to, be

beginning, sometimes at the end, and sometimes neither at s costly that they will probably never be completed. the beginning nor at the end. Some books have no index, Tendeed, if completed, their 'utility may to some extent be 1 The original committee was appointed in 1861. and consisted of impaired by the difficulty of storing them in an accessible Profs. A. Williamson, C. Wheatstone, W. Thomson (Lord Kelvin), W. H. annet. Prof. Turner calculates that the series of maps


total of well over

Miller, Dr. A. Matthiessen, and Mr. F. Jenkins. In the fo'lowing year, still form a pile of paper 30 feet high, weighing about

Messrs. C. Varley. Balfour Stewart, C. W. (Sir William) Siemens, Prof.
Clerk Maxwell, Dr. Joule, Dr. Esselbach, and Sir Charles Bright were

added to the committee.

190 tons.



some have two, one for the subject-matter and one for distinguished direction of Prof. Helmert, who acts as names of authors. The loss of time which arises from

secretary to the association. one's ignorance as to where to look for the index cannot The question of measuring the size of the earth depends be estimated simply by what is spent on the search, but to a great extent on the measurement of arcs of meridiar. must include the time necessary to regain the placidity of So long as we were confined to Europe for the measurethought which is essential to scientific work.

ments of these ares they remained necessarily short, bui It is time we turned to the more serious aspect of larger and larger portions of our globe have become those international associations which directly aim at an accessible to the theodolite, and there is especially on advance of knowledge. Mathematicians have drawn arc which is distinguished by the fact that it is the longes interesting conclusions from the contemplation of ideal possible which can be traced along the land covering the beings who are confined to live on a surface and have no earth's surface. It runs about 30° east of Greenwich, aru knowledge of anything that goes on outside that surface. a large portion of it passes through Africa. Owing to the Our Euclidean geometry would be unknown to them, and great energy and enterprise of Sir David Gill, the work : spiritualistic tricks could be performed by anyone possess- measuring this arc is well in hand, though at the prern ing, even to a minute extent, the power of controlling a moment want of funds threatens to endanger its completius. third dimension. It is, I think, worth while investigating The Egyptian Survey entrusted to Captain Lyons will fiu the extent of the direct knowledge of a third dimension, doubt receive continued support, and by an arrangerteni which makes us so infinitely superior to the two-dimensional entered into between representatives of the German Govern beings. We are able, no doubt, through our eyes, to ment and Sir David Gill at a conference held in Berlin penetrate the depths of space, but we should be unable to in 1896, Germany undertook to carry out the triangulation interpret the impressions of our sight if we had not some through her territory in South-West Africa. I unda. tangible knowledge of three dimensions, and had not stand this work has been done, and the triangulation learned to bring the sense of sight and the sense of touch the Transvaal and the Orange River Colony is also con into harmony. But our sense of touch is confined to a plete. There is still a gap in the southern part of very small distance from the ground on which we stand, Rhodesia, but there is every hope that this will soon to and independently of artificial means of raising ourselves bridged over. The British South African Company haabove the surface of the earth, a layer 6 feet or 7 feet spent 36,000l. on the work and thus has very materiai thick represents the extent of our three-dimensional know

assisted an important enterprise. When the African ar ledge. Compared with the radius of the earth, the thick

is complete it will be connected with the Russian aru ness of such a layer is small enough, for it would represent Roumanian arcs

to form a continuous chain only the thickness of a sheet of paper on a sphere having 105° extending from 70° north to 350 south latitud. a radius of 250 metres; compared with the solar system, I have to point out, however, that, in the opinion and even more so with stellar distance, a thickness of

those best able to judge, the completion of the Soullo layer of 8 feet seems infinitesimal. Yet the infinitesimal African arc is not the only undertaking to which this is essentially different from the zero, and even were our country is called upon to pay attention. The triangu. bodies much smaller than they are we should continue to lation of our own island, excellent as it was when pins have the power to interpret three dimensions. These con- made, has fallen below the accuracy required in modes.. siderations show how important it is for us to increase geodetic work. Until our fundamental triangulation has our knowledge of the earth itself, and to extend it so far

been repeated, the sums which at present are being sperit as possible to the depth below our feet and the height on the detailed survey might find a better use. above our heads.

The main result of the recent work has been that, In passing from the arbitrary units to which we refer far as present measurements allow to judge, the our terrestrial measurements of length, to the scale on

surface of the ocean can be well represented by a surfar which we measure the dimensions of the solar system, and of revolution, and it is not necessary to assume a truir from them to stellar distances, the magnitude of the earth's complicated shape. The mean radius of the earth is or radius or circumference forms an all-important intermediate termined to about 100 metres, which means a possibility quantity. One of the first acts of the French Academy of

of doubt amounting to about i part in 60,000. Sciences, founded in 1666, consisted in organising the work Geodetic work is, however, not confined to measurementof accurately measuring the dimensions of the earth, and of length, for important information may be derived frora this at once enabled Newton to confirm his celebrated theory

an exact knowledge of the acceleration of gravity over its of universal gravitation. As improvements in the methods surface. The introduction of the pendulum of short lengi of measuring kept pace with the work actually accom- intended for relative and not for absolute measurement plished our knowledge steadily increased, but we are still has greatly facilitated this work, and it is hoped that there improving on it. New problems have arisen requiring | pendulum observations may be carried out over still mura more minute study, and the measurements of the shape extended regions. India is setting a good example. It has and size of the earth still remain a question of the first measured two arcs of meridian, and the gravitational work importance. The actual surveys and triangulation required carried out by Captain Burrard, and recently published by for the purpose are of necessity left to the initiative of in- the Royal Society, is of primary importance.' But other dividual States or to the combination of the States primarily wise English colonies require encouragement to do muri concerned, but the general discussion of results, so far as I am assured that measurements of the gravitational cost they apply to the earth as a whole, is entrusted to an stant in Canada would be of the greatest importance. International Geodetic Association, which at present con- The bearing of such work on our knowledge of them sists of twenty-one States. These, together with their earth may perhaps be illustrated by one example. It hrs annual contributions to the general fund, are entered in often been a matter of wonder how mountain chains surt the following table :

as the Himalayas could rest on the lower strata of the

£ earth without crushing them and forcing them in by the Belgium 80 Austria ...

300 Denmark

pure power of their weight, and the most plausible theits 40 ! Portugal


to account for this was found in the idea first suggested Germany 300 Roumania


by Pratt, that the mountain chains must not be chien France 300 Russia

300 pared with a large weight resting on an under-structure Greece

! Sweden ..


but rather with a lighter body partially inmersed in : Great Britain


heavier one.

Mountains, according to this theory, fost in Italy 300 Servia

40 Tapan

the body of the earth very much like icebergs float in | Spain

300 Mexico

water. The truth of this theory can only be tested be 150 Hungary

accurate measurement of the gravitational force, from white The Colonies of the United States of Ame

information may be derived on the distribution of densite Netherlands


300 in the earth's strata near the surface. On the whole, *t: Norway ... 40

far available have confirmed Prar's The Central Bureau of this association is attached to the hypothesis. Royal Geodetic Institute of Potsdam, which is under the More recently another problem has occupied the atten



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