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problems of world-wide interest as relate to the magnetic 
and electric condition of the earth and its atmosphere, not | 
specifically the subject of inquiry of any one country, but | 
of international concern and benefit.’’ ‘he prime purpose, 
therefore, of this department is not to supplant any exist- 
ing organisation, but rather to supplement, in the most 
effective manner possible, the work now being done, and 
to enter only upon such investigations as lie beyond the 
powers and scope of the countries and persons actively 
interested in terrestrial magnetisni and atmospheric 
electricity. 
At first principal stress will be laid upon the complete | 
reduction, discussion and correlation of the existing observ- | 
ational data, and upon early publication of the results in 
suitable form, in order to exhibit the present state of our 
knowledge. In this way will be revealed the gaps to be | 
filed, and the direction of future and supplementary investi- 
gations will be suggested. While, however, this will 
constitute at first the chief work of the department, it is 
likewise proposed to embrace favourable opportunities for 
supplementing, by observation, the existing data and to co- | 
operate with others in the observing of such of the earth’s | 
magnetic and electric phenomena as are of momentary 
occurrence, and the investigation of which is of great im- 
portance. 
Details as to the method of work to be followed by the 
department and the investigations undertaken will be made 
known later. It is proposed that, whenever feasible, those 
having certain pieces of work already in hand shall be invited 
to associate themselves with the department. 
A word of explanation as to the ‘‘ international ’’ character 
of the undertaking. As all the funds are supplied by 
the Carnegie Institution, it will not be possible to organise 
this department in accordance with the customs governing 
organisations the funds of which are contributed by various 
nations in concert, such as, for example, the International 
Geodetic Association, the ‘‘ International Catalogue of 
Scientific Literature,’’ &c. While, however, the basis of 
organisation cannot be *‘ international ’’ in the sense usually 
defined by such bodies, it is the intention to conduct the 
work with the counsel of an advisory board composed of 
representative persons, irrespective of country. The work 
itself, as already stated, is not confined to any one country, 
and in this sense the department is to be truly ** inter- 
national.”’ 
That an important step has been taken by the Carnegie 
Institution will be patent to all who are interested in the 
development of our knowledge of the earth’s magnetism 
and electricity. Prof. Neumayer, one of the representative 
investigators who endorsed the undertaking and promised 
support, expressed himself thus when this project was sub- 
mitted to the Carnegie Institution :— . 
“IT am of opinion that if this plan reaches its fulfilment 
it is the most important step ever taken for the develop- 
ment of our knowledge of the earth’s magnetism. The 
thought which underlies it must appeal to everyone who 
has ever been engaged in geomagnetic investigations. In 
no other branch of geophysics is it more essential to extend 
the inquiries over the entire earth. Magnetic research, to 
be successful, requires the cooperation of the most competent 
investigators of all countries.’’ 
All communications intended for the department should be 
addressed as below. L. A. Bauer. 
Department of Terrestrial Magnetism, Carnegie 
Institution, Washington, D.C. 
| 
The general aim of the work is *' to investigate such | 
| 
The Formation of Coral Reefs. 
In Nature for February 18 there is a paper by Mr. J. S. 
Gardiner giving a concise account of his theory of coral 
reefs. A more extended paper by him on the same subject 
appeared in the Geographical Journal for 1902, and was 
followed last year by one by Mr. Giinther on erosion on 
the west coast of Italy; the latter author proves, on a coast 
with a very strong sand scour and with loose calcareous 
rocks on the fore-shore, that below ‘‘ wind and water ”’ 
mark no erosion to any appreciable extent goes on. Mr. 
Giinther’s observations coincide with those of every day 
experience, and should no one have already protested against 
Mr. Gardiner’s views, will you let me record my most 
NO. 1799, VOL. 69] 
| a general sinking local elevations must occur. 
vigorous dissent? The principles of geology are so little 
understood, and it requires such a level head in sorting out 
the true from the false from among the apparently con- 
flicting evidences that one has to deal with, that I think 
when such a glaring misconception of the processes of 
nature as that of Mr. Gardiner’s is repeated in scientific 
journals some stand should be made before more mischief 
is done. It is a disadvantage on my part not to have 
worked on coral reefs myself, but 1 have been working for 
ten years on a coast which is fringed with coral reefs only 
a short way from where I have seen it, and | have there- 
fore been able to study the base of the reefs without the 
disguising covering of coral limestone. I have seen beaches 
crowded with the shells of animals still living in the adjoin- 
ing sea, raised two and three hundred feet above sea- 
level, and a short distance away I have seen consolidated 
sand-dunes going far below sea-level; while from the 
submerged plateau the edge of which is called the Agulhas 
Bank, Dr. Gilchrist has dredged large water-worn boulders 
far out to sea. South Africa generally.is a rising area, but in 
a sinking area the exact converse is true, namely, that with 
This last is 
not a new statement of fact, but a well established experi- 
ence, and one that has been treated of again and again, for 
instance, by Suess, in his ‘‘ Antlitz der Erde,’’ vol. ii. 
chapter i., and is one which I believe can be proved on any 
coast—it is well brought out in Mr. Giinther’s paper, and 
in many descriptions of coral islands; with such a state- 
ment before one, I am at a loss to understand where the 
room comes in for Mr. Gardiner’s theory, or where are the 
difficulties which led to the manufacture of the hypotheses of 
Messrs. Murray and Agassiz. The one fundamental idea 
that dominates the whole conception of the earth’s struc- 
ture is that the crust is never at rest, but is incessantly 
rising and falling; and a corollary is that each great rise 
or fall is never continuous, but is the result of the surplus 
of a series of + and — movements. If we are to adopt 
Mr. Gardiner’s view that submarine erosion can cut down 
solid rock to 200 fathoms below the surface of the water, 
geology must be deposed from its pedestal as a science, and 
relegated to the class which includes gnostic theology and 
such like. Ernest H. L. Scnwarz. 
South African Museum, Cape Town, March 9- 
Mr. Scuwarz, as far as I understand him, questions the 
effects, if any, of submarine erosion and the necessity for 
any view except that of subsidence to explain the formation 
of coral reefs. I fail to see the parallel between the west 
coast of Italy and the Maldives, but it is obvious that 
wherever submarine currents exist there must be erosion, 
its extent depending on their force, &c. I would refer Mr. 
Schwarz to the detailed work on currents and the effects 
of organisms in my full paper on the Maldive and Lacca- 
dive Archipelagoes in the ‘‘ Fauna and Geography of the 
Maldives and Laccadives.’’ He will find there certain refer- 
ences, but in the same connection he should read Prof. 
Agassiz’s numerous papers issued from the Museum of 
Comparative Zoology at Harvard, and Prof. Max Weber’s 
and Captain Tydeman’s reports on the Siboga Expedition. 
In common with most recent workers on the subject I 
have treated of my difficulties in respect to the acceptance 
of the subsidence theory in the paper already cited and in 
my report on Fiji, and Mr. Schwarz will pardon me if I 
do not feel disposed to re-state them. The gentlemen he 
refers to have probably stated theirs. We are doubtless well 
aware of the general facts mentioned by Mr. Schwarz, and 
I feel sure that we shall be only too happy if he will explain 
our difficulties and assist us in arriving at the truth on 
this important question. 
[ may take this opportunity of pointing out that, accord- 
ing to the report of the Coral Reef Committee, Funafuti 
has probably been largely formed by subsidence, and hence 
may be an example of the fourth mode of formation 
mentioned in my article. J. StanLey GARDINER. 
Zoological Laboratory, Cambridge, March 31. 
Demonstration of Magnetostriction. 
In a recent number of Nature (March 24) Prof. H. 
Nagaoka describes a method for demonstrating the change 
of length of an iron wire by magnetisation. I have for 
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