260 
NATURE 
[JANUARY 10, 1907 
tion of each calculated. A 
atives of all the sciences, 
ral list, including represent- 
also compiled by interpola- 
tion, but neither this nor .... separate lists are published. 
An interesting table is given showing the divergences 
between the ten judges in the case of psychology, as an 
illustration. The order of merit given by one of the judges 
is very much more accordant with the average order than 
those of the others, and they differ considerably inter se, 
though more, if we understand the table rightly, in the 
case of those at the bottom of the list than of those 
towards the top. Of the first hundred scientific men on 
the list who are eligible, sixty-one are included among 
the ninety-seven members of the National Academy - of 
Sciences. The discussion of the grades and probable errors 
is continued in ,Science for November 30, and in a third 
and concluding article in the issue for December 7 Prof. 
Cattell investigates the geographical distribution of 
American men of science, according to place of birth and 
place of residence. The figures as regards the former are 
extremely striking. The production or “‘ birth-rate’’ of 
men of science per million of the population ranges from 
about 109 in Massachusetts—which stands far above the 
other States—and eighty-seven in Connecticut down to 
rates of only one.or two in several of the southern States. 
It is argued that differences in stock can scarcely be great 
enough to account for this, and that accordingly the pro- 
duction of scientific men must be largely a matter of 
circumstance. As regards the place of residence, interest- 
ing tables are given showing the institutions with which 
the men of science taken into account are connected. The 
work forms part of an extended investigation which Prof. 
Cattell has now been conducting for some ten years, and 
on which he has published several previous memoirs. 
WAVE ACTION IN RELATION TO 
ENGINEERING STRUCTURES. 
A PAPER on wave action in relation to engineering 
structures, by Major D. D. Gaillard, issued as a pro- 
fessional paper (No. 31) of the Corps of Engineers of the 
United States Army, contains a great deal of information 
useful to engineers engaged in designing and constructing 
sea defences and other works subject to wave action. 
The first part of the book is devoted to a general con- 
sideration of the theory of the formation of waves, and 
to a notice of the information that already exists as to 
this. This, as the author remarks, is embraced in so 
many volumes that the work of comparing theoretical and 
observed wave characteristics is rendered very tedious. 
The investigations that have previously been made into 
wave action, and of which the results have been pub- 
lished, relate principally to deep-water waves, whereas 
there is very little recorded information as to the action 
of waves in comparatively still water to which engineering 
structures are exposed. 
Major Gaillard, the author of this book, was for several 
years engaged upon works of harbour improvement on the 
South Atlantic coast and the Great Lakes of America. 
Although the waves to be dealt with in Lake Superior 
are not of the magnitude of those in the open sea, yet 
the author’s observations cover waves of various dimen- 
sions extending up to 300 feet in length and 23 feet in 
height, and the results are recorded of several hundred 
observations of their length, height, period, and depth in 
which they broke and to which their effect extended. 
Numerous examples are also given of the effect of waves 
in moving large masses of stone and other material. The 
force of the waves breaking on piers, and other marine 
structures, was measured both by the marine dynamometer 
of the class used by Mr. Thomas Stevenson more than 
half a century ago and also by dynamometers of special 
construction made under the author’s directions. The 
general type of the Stevenson dynamometer used had discs 
of from 3 inches to 9 inches, with springs varying in 
strength from ro Ib. to 50 lb. for every inch of elongation. 
The greatest dynamical force recorded with these when 
used at Dunbar, in Scotland, was 7840 Ib. per square foot 
with waves about 20 feet high. These dynamometers only 
measure the dynamic, and not the static, pressure, and 
give only a maximum reading for a storm observation, and 
NO. 1941, VOL. 75 
are affected in their working when ‘there is much sand in 
the water. 
The instruments invented and used by the author, besides 
the Stevenson type, consisted, in one case, of a steel 
plate, having an area of one square foot, attached to two 
elliptical springs similar to those used for carriages, the 
distance between their centres being 6 inches, the read- 
ing of the amount of compression due to the action of 
the wave being recorded by a rod attached to an index 
which acted on a paraffin surface. The instrument, before 
being fixed, was rated by having weights placed on the 
plates and noting the corresponding compressions. The 
other dynamometer used by Major Gaillard consisted of a 
plate covering a square foot attached to a horizontal 
cylinder filled with water; over the flange of this cylinder 
was placed a diaphragm of india-rubber 3-inch in thick- 
ness, having a face of one square foot. A 3-inch pipe 
led from the cylinder to a tank located in the observing 
station on the pier. From this pipe there was a com- 
munication to a modified form of Bourdon gauge fixed 
19 feet above the centre of the diaphragm, and which 
registered pressures up to 30 lb. per square inch. Com- 
munication with the tank having been shut off, any 
pressure applied to the diaphragm was transmitted by the 
confined hydrostatic column to the gauge. More than a 
thousand readings of wave action were taken with this 
class of dynamometer while the author was in charge of 
the works, but only two storms of consequence were 
encountered. So far as the observations went, the instru- 
ment appears to have given satisfactory results. 
The text is accompanied by a number of illustrations 
taken from photographs of waves. 
SCIENCE IN EXAMINATIONS FOR THE 
HIGHER CIVIL SERVICE, ; 
THE kind of education received and the subjects studied 
by future civil servants must have a great and far- 
reaching effect upon the influence exerted by the public 
departments which administer the multitudinous and diverse 
affairs of our scattered Empire. The methods adopted for 
the selection of such officers must, therefore, be wisely 
chosen, and, in any examinations designed to facilitate the 
process of discrimination between men offering themselves 
for these positions, the subjects in which candidates are 
tested must be those appropriately related to the work of 
the department in which successful candidates will be 
employed, and, at the same time, those most likely to 
test essential fitness for public work. These and similar 
principles have been widely canvassed recently both in 
public addresses and in the Press. Certain changes in the 
examinations for the selection of Foreign Office clerks 
and attachés in the Diplomatic Service are to be intro+ 
duced, and the new regulations have not met with universal 
approval. It will assist clearness of thought first to com- 
pare briefly the existing regulations for the appointments 
concerned with those shortly to come into force. 
Candidates for clerkships on the establishment of the 
Foreign Office and for attachéships in the Diplomatic 
Service will, after July 1, instead of being examined 
according to special regulations which have governed these 
appointments hitherto, be required to take the combined 
examination for open competitions for the Home Civil 
Service (class i.), India Civil Service, and Eastern Cadet- 
ships. This decision profoundly modifies the conditions 
of selection for service in the Foreign Office and the 
Diplomatic Service. In the past there have been nine 
obligatory subjects—arithmetic, handwriting and ortho- 
graphy, English composition, précis writing, French, 
German, general intelligence, geography, and the history 
of Europe from 1789 to 1880 inclusive. In addition, candi- 
dates have been able to offer any two of the following 
languages, viz., Latin, Italian, Spanish, Portuguese, Russian, 
modern Greek, and Arabic. In the examination which 
such candidates will have to take after July 1 next, papers — 
will be set in thirty-two different subjects, from which a 
selection must be made by the candidate. French and 
German will be the only obligatory subjects, and candi- 
dates will have to reach a high qualifying standard in 
translation, composition, and oral examination in be** 
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