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vector, which can have no scalar part. Again, in the formulæ of Rankine and Weyrauch. In a series Exercise (13) we have by definition
of three tables the author gives the values of the earth a? a3
pressure against walls of different heights as deduced ca=1 +8+ 1.2.3
by these three formulæ, and the results agree so well where
that it is evident that any one of the three methods is a=a.a, a’=aa.a, a:=a.aa a,
equally trustworthy from the practical point of view. and we are to prove that
The results obtained in the preceding chapters are Cd = cos a +a, sin a,
applied in chapter iv. to the design of various types where a is the length of a, and a, is the unit vector
of retaining walls; and the important problem of the
determination of the necessary thickness at the base of along a. Now according to Gibbs a.a= +a, so that all the terms of the assumed expansion must be posi- earth pressure is fully discussed for each type of wall.
a retaining wall in order that it may be stable under tive. How then can they give the sine and cosine? The statements are true only if we use the Hamil
The last chapter of the book is devoted to masonry tonian vector whose square is minus the square of its
dams, which, as the author points out, are simply length. The linear vector function is introduced for
a particular case of retaining wall, with the material the discussion of the kinetics of a rigid body. This is
sustained practically frictionless; it is shown that the
most economical profile, theoretically, is a triangular purely Hamiltonian, and is very good so far as it goes. The investigation, however, seems to lack here
one, but in practice this is an impossible section.
The modification needed in order that the dam may and there the strength and spontaneity of Tait's classical discussion.
have a certain thickness at the top is then discussed, and the pentagonal profile deduced. It is shown that
this theoretical profile is the basal form of all modern RETAINING WALLS AND ROAD BRIDGES.
high dams. The book should prove especially useful (1) Graphical Determination of Earth Slopes, Retain- to civil engineering students during their final college ing Walls, and Dams. By Prof. C. Prelini. Pp. ix+
year. 129. (London : A. Constable and Co., Ltd., 1908.) (2) While many text-books have been devoted to the Price Ss. net.
design of railway bridges, but little attention has (2) The Design of Highway Bridges, and the Calcula- been hitherto given to the equally important question
tion of Stresses in Bridge Trusses. By Prof. M. S. of the design of road bridges, and, although the work Ketchum. Pp. xxi+ 544. (New York: The Engin- of calculating the stresses in the different members eering News Publishing Co.; London : A. Constable
is the same for both types, there are, owing to the and Co., Ltd., 1908.) Price 16s. net.
very different requirements to be met, radical differHIS book brings together for the use of the ences in the design of the two classes of bridge. This
engineering student in a handy form for book, therefore, meets a distinct want, and it will be reference the various graphical methods due to Cul- especially useful to the young designer, in view of mann, Rebhann, and others, for solving problems the fact that the author has given special attention connected with earth pressures.
to the problem of the design of the substructure, which The first chapter treats of the stability of earth is usually quite neglected in books on bridge design, slopes; the cohesive force in a bank of earth is deter- An entire chapter has been devoted to the design of mined by graphical methods, and hence is deduced the floor beams, floors, shoes, and pedestals, and other most probable plane of sliding; by means of the similar details, and it is in regard to such matters parabola of cohesion the various slopes of equilibrium that the young engineer most commonly finds the for various heights of bank are determined, and its need of help and guidance. application to practice is then discussed; the consider- The ninth chapter will prove of considerable use, not able economy in excavating deep trenches with slopes only to the student, but also to the teacher; as the correctly designed is proved by worked out examples. author points out, in order to obtain a thorough
In the second chapter the design of retaining walls knowledge of the calculation of stresses in bridge is taken up; the author points out that all the various trusses, it is essential that the student should work theories which have been employed can be divided through numerous problems—altogether twenty-four into two groups, (a) those depending on the theory problems are worked out in detail in this section of the of the sliding prism, (b) those depending on analytical book, and a second similar one has been added to theory. A graphical solution, due to Rebhann, of the each of the twenty-four problems as a further exercise sliding prism type is then given ; this method is then for the student to solve with the help afforded by the applied to a series of practical cases, both for retaining worked-out example; some of the solutions are obwalls when surcharged, and when free of surcharge. tained graphically, others by algebraic methods. The variation of pressure with height of wall, and Another valuable section is that devoted to influence position of the centre of pressure are dealt with, and diagrams, or influence lines, which are required in also the effect of cohesion on the pressure against studying the variation of the effect of a moving load retaining walls, and the pressure of passive resistance or system of loads, on a truss. of the earth in the case of abutments which are pushed Special attention has been given to the design of outwards by arches.
high truss steel bridges, and to plate girder bridges, In the next chapter there is an analytical demon- and this section of the book is well illustrated with stration of Rebhann's theory, and brief statements of reproductions of working drawings, which, in spite
of the necessary small scale, are perfectly clear and Das Seelenleben der Tiere. By Dr. P. Ohm. Pp. 117. distinct in all the essential details. The stresses in, (Stuttgart: Neue Weltanschauung, 1909.) and the design of, solid masonry arches and culverts This little book is the fourth of a series called form the subject of two chapters, and, though there
“ Weltanschauungs-Fragen," and apparently intended is nothing specially novel in the treatment adopted, of Haeckel. Consequently, Dr. Ohm brings forward
to include contributions to the monistic philosophy these sections of the book will be welcome to the the two principal theories of animal intelligence—one draughtsman who is engaged in this branch of bridge that it is totally different in kind from human, and design, especially as the author has given some useful the other that it is the product of evolution, and notes on the theory of reinforced concrete.
differs only in degree, but is essentially of the same In part iii. of the book there is a full critical investi- subject
, and noticing the opinions held by various
nature. After a brief historical introduction to the gation of an existing structure—the weights, costs. authors from Plato to Wasmann, Darwin, and and efficiencies of the members of a Pratt highway Harold Höfding, Dr. Ohm speaks of the dawning bridge of 160 feet span are fully worked out, and intelligence indicated in Protista, sponges, Medusa, the errors in design pointed out, and the modifications Hydra, molluscs, &c., and then inserts à chapter on which would improve the design are suggested. There
instinct to controvert the view advocated by Wasis no doubt that such an investigation is bound to
mann that it is a perfect and divine inspiration, quite
different from reason. Here he deals especially with make students familiar with bridge details, and we the manifestations and imperfections of the intelliwould commend this method to the notice of engineer- gence of insects, especially ants and bees. ing teachers.
T. H. B. Another chapter is devoted to the “Seelenleben"
(“' soul-life," or, more correctly, intelligence) of OUR BOOK SHELF.
insects and spiders, with special reference to their Die Strahlen der positiven Elektrizität. By Prof. E. is given of the Indian tree-ant (@cophylla smarag
eyes, antennæ, sense of direction, &c., and a figure Gehrcke. Pp. xi+124. (Leipzig : S. Hirzel, 1909.) | dina) using one of its own larvæ to spin threads. Price 4.50 marks.
An illustration is also given of the large garden At a moment when scientific thought is being con- diadem spider and its web. Another chapter follows, centrated on the consideration of the nature of posi- on the senses, habits, and intelligence of vertebrate tive electricity, we can only welcome the appearance of animals, and the book concludes with a comparison a book which aims at bringing together, in the short between human and animal intelligence; and the compass of a hundred pages, all the principal facts author regards the faculty of speech as the essential bearing on the subject. "This Prof. Gehrcke has done, difference between them. A short bibliography is and he has done it well, for, with the exception of appended. a few slight omissions, he has put before his reader Dr. Ohm has written a thoughtful little book, and all that is essential with regard to positive rays. has dealt with a difficult subject fairly and moderBut we could wish that more than this had been ately. His work will be read with interest by done, for it is a little disappointing to find the results students interested in the important questions with of experiments given, often with little, if anything, to which it deals; but everyone is so much influenced indicate the theoretical deductions which can be drawn by preconceived ideas, on one side or another, that from them.. Indeed, not infrequently the opinions it is almost impossible to form an unbiassed opinion of different investigators as to the interpretation of about them.
W. F. K. the results of experiments are recorded without any comment as to the relative merits of rival theories. Comment Former un Esprit. By Dr. Toulouse. No doubt it was the intention of the author to keep
Deuxième Édition. Pp.. X+260. (Paris : Librairie the work within definite limits, but it seems that
Hachette et Cie., 1908.) much has been sacrificed merely for the sake of | This book is the reply to a request for ten lessons brevity. In no part of the book is this more appar- to professional teachers and parents which should ement than in the portion devoted to radio-activity and body what Dr. Toulouse's experience as a psychologist the nature of the a rays. Here descriptions are often and a medical man has taught him to think essential so short that it is questionable whether anyone not to “ the cultivation of an intelligence.” He starts already fully acquainted with the subject will be able from a position with which critics of educational into follow the reasoning.
stitutions on this side of the Channel have made us In the part dealing with radio-activity there are a familiar; “ we teach everything in school to-day few inaccuracies which call for comment. On p. 90 except how to think and how to act.” His remedy is the author states that it is usually supposed that also familiar-education should aim at teaching us one a particle is given off from each atom during any not so much to know as how to apply knowledge to radio-active process involving the emission of such the regulation of the important affairs of life. To particles. In view of the work of Bronson, who achieve this end it must train us, in accordance with showed, for example, that atom of thorium sound principles of "method" (in the Cartesian emanation, in breaking up, gives off four times as sense), to observe, to judge, to feel, to act. The many a particles as an atom of thorium B or C, this author's discussion of these methodical principles is is clearly not the case. Again, the table on p. 89 broad-minded and suggestive, but it is too brief and contains some mistakes. The volatilisation point of schematic to be of much direct service to the teacher radium A, given as 1000° C., is too high, and that in the class-room or the parent in the home. His of radium C, as 1100° C., is too low. The volatilisa- recommendations have much more value when they tion point of radium B is given as 20° C., instead either express the practical wisdom of a man who has of 600° C. That radium B can escape, at ordinary managed his life successfully or deal with specific temperatures, from a surface coated with active topics on which his experience as a medical psychodeposit is correct, but the phenomenon is not due to logist gives him authority. Under the latter heading any true volatility of the substance at ordinary tem- attention may be directed to a vigorous argument for peratures, and has been explained on quite different the frank instruction of boys and girls in "the lines.
phenomena of life.”
LETTERS TO THE EDITOR.
The (The Editor does not hold himself responsible for opinions
the properties of hæmoglobin but not the others. expressed by his correspondents. Neither can he undertake
matter being in this unsatisfactory state, it is very to return, or to correspond with the writers of, rejected should re-investigate the blood of Lernanthropus.
desirable that someone, to whom the opportunity is offered, manuscripis intended for this or any other part of NATURE. No notice is taken of anonymous communications.]
New College, Oxford.
GEOFFREY Smith, Visibility of Halley's Comet. The discovery of Halley's comet at a time so far pre
MAGNETIC STORM OF SEPTEMBER 25. ceding the date of perihelion passage adds another proof of the great capacity of the photographic method. The
R. CHREE, F.R.S., has sent us the following DR.
communication on the above :interesting point to many observers is as to when the comet will become visible to them as a telescopic object. rapid oscillatory movements that are usually associated
The magnetic storm of September 25 exhibited the This must, of course, depend in a large measure upon the diameter of their glasses and on their powers of vision.
with the appearance of aurora. As recorded at Kew, After the present moon has left the sky, say during the
the storm commenced suddenly at about 11.43 a.m. second week in October, the comet ought to have increased During the next nine hours there was an almost unin. in light sufficiently for it to be observed in a 12-inch terrupted succession of large oscillatory movements in telescope. The calculated magnitude of the comet will be the magnetic curves, especially those of declination 14) on October 15, and its distance from the earth about and horizontal force. The storm was of comparatively 230 millions of miles. Its apparent position will then be short duration, no movements of any great size being five degrees west of y Geminorum, and near 72 Orionis. recorded after 8.30 p.m. on September 25, and by On October 16 the comet will be just two degrees south of 71 Orionis (mag. 5:5), and ought to be visible as a very left. When the storm was at its height the oscillatory
I a.m. on September 26 little trace of disturbance was faint nebulosity, especially if the night is good. The transparency of the air has an important influence on the
mr.ovements were so rapid that the record left on the perception and aspect of faint comets and nebulæ, for a
photographic paper was frequently too faint to show really suitable sky will enable objects to be glimpsed which minute details, and the limits of registration were at are utterly invisible on bad nights when there is diffused times exceeded. light, thin cloud, mist, or fog prevalent. The comet will At the commencement there would appear to have be visible in an excellent position nearly all night during been an exceedingly rapid oscillatory movement of the most of the winter, but will continue small and faint until declination needle, after which the needle moved to it blazes out next April.
W. F. DENNING. the east continuously for about 15 minutes. After
the first 12 minutes, during which a movement of The Presence of Hæmoglobin in Invertebrate Blood.72' was recorded, the trace got off the sheet, so that May I make use of your columns to correct a statement
the full extent of the easterly drift is not shown. in my article on Crustacea in vol. iv. of the “.Cambridge but, after some oscillatory movements of the needle,
After a few minutes' absence the trace reappeared, Natural History," which I am afraid may seriously mislead the reader? Referring to the alleged presence of
the trace got off the sheet again on the same side as hæmoglobin in the blood of Branchipus and Daphnia, I
before at about 12.12 p.m., and remained off on this have stated in a footnote on p. 30 that the fact that the occasion for nearly 40 minutes. During the whole of red blood of Lernanthropus has been proved not to con- this time the needle pointed at least 70'-at times, tain hæmnoglobin throws doubt on the reality of its presence probably, a good deal more—t the east of its normal in the other two animals. At the time of writing I was position. After coming on the sheet about 12.52, the not aware that the authority on which the presence of trace exhibited some minor oscillations superposed on a hæmoglobin in Branchipus and Daphnia rested, and rapid drift across the sheet. The entire width, repreI was inclined to impugn, was Sir Ray Lankester, who, in senting 207', was crossed in less than half an hour, the late 'sixties and early 'seventies, published a series of researches which laid the foundation of a comparative the opposite side. The needle then pointed about 10 to
and the trace at about 1.20 p.m. got off the sheet on knowledge of the distribution of hæmoglobin and similar respiratory pigments in the animal kingdom (see especially
the west of its normal position. Between 1.20 p.m. and Proc. Roy. Soc., vol. xxi., December, 1872, P. 70). After 8.30 p.m. there were a number of large oscillations, reading these articles it is clear to me that Sir Ray
movements of 40', 60', or more, now east, now west, Lankester's statement as to the presence of hæmoglobin taking place in the course of a few minutes. The in the blood of Branchipus and Daphnia, resting as it largest of the rapid oscillations clearly shown took place does on careful microspectroscopic examination, is quite between about 8.7 and 8.22 p.m., a westerly moveunaffected by what may
not be the case in ment of 98' being followed by an easterly movement Lernanthropus, so that I can only withdraw my footnote of 84'. The disturbance shown by the horizontal-force with many apologies to him and to readers of the
no less remarkable. The commencing bridge Natural History." With regard to Lernanthropus
movement at 11.43 a.m. went beyond the lower limit and its allies, small crustacca parasitic on fish and mussels,
of registration, a fall of 430 y taking place in about which possess a closed vascular system containing a red
10 minutes. At this time the trace was off the sheet Muid, there is still some doubt. Van Beneden, who discovered Lernanthropus in 1880,
for only about 5 minutes. After reappearing it showed Anzeiger, Bd. iii., p. 35) that he examined the blood large oscillations. By 12.53 p.m. it had crossed the spectroscopically, and found the oxyhæmoglobin lines.
sheet to the other side, the change of force during More recently Dr. Steuer (Arbeiten Zool. Inst. Wien, one period of 13 minutes being no less than 625 y. vol. xv., p. 14. 1903) sent numerous specimens of an The trace was off the sheet continuously from 3.55 to allied form, Mytilicola, to Prof. R. von Zeynek in Vienna, 5.10 p.m., the horizontal force during the whole of who came to the conclusion that the blood did not contain this time exceeding its normal value by more than hæmoglobin, since (1) with glacial acetic acid and sodium
300 y. Except when off the sheet, the trace showed chloride no hæmin crystals were obtained ; (2) after reduc
continuous large oscillatory movements during the tion with potassium cyanide and ammonium sulphide, the
whole afternoon. The largest clearly shown was characteristic reduced hæmoglobin lines were not formed; partly synchronous with the large declination oscilla(3) there was no hæmochromogen reaction. Curiously enough, we are not told whether the simple
tion near 8 p.m. already described; it consisted of a examination of the blood gives the oxyhæmoglobin lines,
rise of 520 y and fall of 710 y, all in the course of as Van Beneden stated, or not, so that we are left in doubt
17 minutes. whether Van Beneden was altogether in error or the red
The declination range, 20 7', and the horizontal-force
The display on
range, 740 y, actually recorded, represent merely the time thereafter. It is possible, of course, that the full width of the photographic paper. How much external currents have partly demagnetised the earth, these ranges were exceeded it is impossible to say, or at least modified its distribution of magnetism, but, judging by the look of the curves, the excess was and that there are recuperative tendencies tending to probably considerable. The vertical-force trace got off cause reversion to what is for the time being a more the sheet only on one side, and this element would stable distribution; but if this be the true explanation. appear to have been less disturbed than the other two. the demagnetising action and the recuperative terStill, as the trace was off the sheet continuously for dencies are presumably in action during the cour ** nearly an hour after 3.35 p.m., the chances are of the storm, and profoundly modify the magnetic that the true range exceeded somewhat largely the phenomena. To many minds subscription to some range 530 y actually recorded. The duration of the theory may be a necessity for intellectual comfort. storm was comparatively short, but whilst it lasted it but in the case of magnetic storms reservation of exhibited an energy which has been very seldom judgment appears at present the
scientific rivalled at Kew. The oscillatory movements were attitude. quite as rapid as those of October 31, 1903, and the
to range of the elements has probably not been exceeded
In addition the foregoing we have during the last twenty years, not even during the great
ceived the following communication from Prot. storm of February 13, 1892.
A. Fowler, of the Imperial College of Sciene Magnetic storms such as the present inevitably sible occurrence of a magnetic storm and aurora!
and Technology, South Kensington :-The poss create an interest in the explanations that have been advanced to account for the phenomenon.
September 24 25
suggested theories of Arrhenius and of Nordmann, the theories by observations of the 'large spot which and researches of Birkeland, and the deductions made
then on the sun's disc. On September 24 the spot was by Maunder from the Greenwich disturbances all point be the most favourable position in relation to magnetic
a little west of the central meridian- which appears to to the sun as the ultimate source, and to some form of discharge--ions, electrons, or such like carriers of disturbances and spectroscopic observations showed electricity-as the immediate vehicle. The electrical
that it was of the same disturbed type as the spot nature of aurora is difficult to dispute, and the associated with the great magnetic storm of October fact that storms like the present appear to be in-31, 1903. (NATURE, vol. Ixix., p. 6). variably associated with aurora visible far outside
On Friday evening (September 24) the sky was overthe polar regions unquestionably supports in some
cast, and it did not then occur to me to test the ways theories such those of Birkeland
possible presence of aurora by the spectroscope. On Arrhenius.
Saturday evening, however, although the sky was at When We come, however, to details, difficulties first completely clouded over, the spectroscope gave present themselves. If magnetic storms are directly unmistakable evidence that an auroral display was in due to the electrical currents which render the upper progress. From 6.40 to about 7.30 (the sun set at atinosphere luminous, how comes it to pass that the 5-52), the whole sky was filled with a feeble light, with visual phenomena of aurora are so constantly chang- brighter patches here and there, and the characteristic ing, whilst even in the most conspicuously variable of green line of the auroral spectrum was seen in every magnetic storms the larger movements of the magnets direction. The greatest intensity was at first near the take usually 5,
zenith, but the line was easily visible over the entire plish, the force appearing to alter at a nearly sky, and was even seen in the light reflected by a uniform rate for minutes on end? The relatively pocket handkerchief. This condition continued with gradual nature of the magnetic change is a true pheno- diminished brightness until near 8 p.m. , Between 8 menon-as clearly indicated by the short period and 9 o'clock the display was very feeble, but shortly magnets of thc Eschenhagen pattern, as in the larger after 9 the auroral line was again fairly distinct in a Kew magnets with periods of 10 seconds or more. faintly luminous belt about 100 above the northern There is, again, the very remarkable fact that when horizon. After 9.30 no
evidence of aurora
was we go to high latitudes, where aurora and magnetic obtained, although the sky was then partially clear. disturbance are both almost daily occurrences, the
The general distribution of the green line over the association of the two phenomena becomes much heavens in clearer skies has been occasionally noted more difficult, if not impossible, to recognise. The by Angström and others, but I have not yet found any
ence of visible aurora during active magnetic dis- previous record of such a wide diffusion of the auroral turbances may be reasonably accounted for during light when the sky was completely clouded. If wholly the Arctic summer, when the sun is above the horizon, above the clouds, the aurora must have been of but it is a different matter when we find the magnets extraordinary brightness in order to produce this rather quieter than usual during the occurrence of a effect. bright aurora. Unless we are to assume a funda- Besides the green line, there were three fainter mental difference of type between auroras presenting nebulous lines or bands in the green and blue, which the same spectroscopic lines, or a variety of sources have been frequently mentioned by previous observers. for different magnetic storms, there is a difficulty | A careful search was made for the red line which which is not easily surmounted. The only explanation
appears in “crimson
auroræ, but its presence was that has occurred to me is the possibility that the visual not even suspected. phenomena may represent merely intense local con- As
to the sun-spot, there
brilliant recentration of electrical current, and that the main versal of the Cline of hydrogen over portion of the discharge frequently makes no appeal the umbræ when I observed it at
p.m. to the eye, and is of a much more steady and persistent September 24, and on opening the slit it character. Another difficulty in regarding the pheno- was clear that this appearance was produced by mena of magnetic storms as entirely and directly due a very bright overlying prominence. Reversals of to the action of electrical currents associated with the chromospheric lines b, and 1474 K were also susaurora is that it is a frequent occurrence-as on the pected, but the observations were stopped by clouds. present occasion—for the horizontal force to be con- | According to Tacchini and Lockyer, it is the promin. siderably depressed below the normal value when the ence, rather than the spot, which should be considered storm has apparently ceased and for some considerable as related to the magnetic disturbance.
August 21 in connection with the Rheims meeting of
the following week. A useful feature is the series of THE successful aviation week recently concluded illustrations, each showing in one figure a collection
do tion, if that subject is not sufficiently popular already. much the same way that the early history of the subThe large number of newspapers and periodicals ject is summarised in the interesting old “ Tableau devoted to aërial navigation is, however, sufficient d'Aviation ” of fame. Of these we reproduce the two evidence of the amount of public interest which illustrations of the most recent aëroplanes. The article centres round the new form of locomotion. At a concludes with a calendar of “ the great dates of railway bookstall at Tarbes, in the Pyrenees, a few aviation,” which is here given, with addition of the weeks back, the present writer saw no fewer than | Rheims records :five different papers devoted to flying machines. Possibly the number of such journals is equal to, even
Distance and Duration greater than, or at any rate comparable with, the number of successful flights that have been per
Satory Flight of 300 metres. formed; it certainly appears as if the frequency with
Sept. & Oct. which a new journal comes out is not small in pro
Wright Bros. Kitty Hawk Flights of 17 to 38 km. portion to the frequency of aeronautical successes.
Nov. 12, 1906 Santos Du.
Bagatelle 220 m. in a straight line. Indeed, at the present rate, the assigning of new Tan. 13, 1908
Kilometre in closed circuit, titles to these journals will soon take the form of a July 6, 1908
Prize for hour.
Fort Meyer. 63.975 km. in ih. 3m. 155. problem in permutations and combinations.
Oct. 10, 1908
ih. gm. 455., two persons. When it is attempted to draw scientific conclusions Oct. 30, 1908
Bouy to from these successful flights there is not, after all,
First actual journey, 27 km. Oct. 31, 1908
Blériot Toury to so very much to be said. The difference between a
Artenay & machine that will fly one mile and a machine that
First circular trip.
123 km. in 2h. 18m. 33.6s. will fly a hundred miles is mainly that the latter
June 5, 19-9
Camp de must be able to carry a heavier load in the form of
ih. 7m. 355. on monoplane. July 18, 1909 Paulhan
150 metres altitude on bipetrol or other fuel than the former. In the case of
July 25, 1909
Sangatte to plane. high flights the same remarks apply, though the
Channel flight, 37 m. construction of a machine which is capable of ascend
Aug. 4, 1909
C. de Châlons 2h. tom. on biplane.
2h. 27m., time rerord ing or safely descending at a considerable angle to Aug. 23, 1909
10 km. in 8m. 37.6s. (speed). the horizon presents many points of scientific interest
10 km. in 8m. 4'45. which, no doubt, will receive the attention they de.
Aug. 25, 1909
131 km. in 2h. 43m. 24*8s. Aug. 26, 1909
154'5 km. in 2h. 13m. 9'6s. serve sooner or later, unbeknown to the average
180 km. in 3h. 4m. 56' 45. newspaper reader. In saying that when aviation Aug. 28, 1909
Altitude 120-130 m. takes the form of record-breaking it ceases to be a science and becomes a sport, we are, of course, not taking into account all the work of an experimental When the newspapers state that one portion of the character in the construction and perfection of motors, course has come to be called “the valley of death," propellers, and aëroplanes which has to be gone from the numerous wrecks that every day strew its through behind the scenes before the sport can be in- fields, and when we refer to the accidents to Paulhan, dulged in. We have, however, failed to find that any Fournier, Blériot, and still later to the death of very definite and striking new result has been proved Lefèbvre and the accidents to Lieut. Calderara, to by the recent triumphs.
Bossi, and to Le Blanc, it will be seen that aëroplane It would seem, in fact, as if writers on the subject triumphs are being bought at the expense of many were directing their attention to the early history of thousands of pounds spent in rebuilding completely aërial navigation to make up for the fact that there smashed-up machines, not to mention the risk to is very little to write about in a mere statement of life and limb. records. Under the title of lla, a weekly journal is Of course, a considerable proportion of these acciappearing in connection with the International Aëro- dents are undoubtedly accidents in the true sense of nautical Exhibition at Frankfurt, of which the his- the word, but when we read, as we have done over torical section is an important feature. It is interesting and over again, that machines have suddenly stonned to revive acquaintance with the early, and in many dead from no explicable cause, and then suddenly cases fantastic, devices of Barthélemy Lourenço de plunged to the ground, the idea of longitudinal inGrisman, Besnier, Jacob Degen, Blanchard, the stability at once suggests itself, and the obvious Minerva of Robertson, with its suspended ship and remedy is that aviators should wait until this subject cabins, and an old cartoon of an omnibus and horses has at least been thrashed out mathematically, or hanging from a balloon. As for Lourenço, a special should devote a fraction of the sum they spend on number (Illustrierte Aëronautische Mitteilungen xiii. repairs of broken parts to furnishing the assistance 17, Ila iii.) contains references to his exploits in view of which would enable the theoretical investigations to August 8 of this vear being the 200th anniversary be pushed forward without delay instead of being of his supposed flight. The article by Mr. B. Wilhelm hung up for months at a time owing to pressure of is prefaced by short editorial note by Capt. other work. H. W. L. Moedebeck, and seems to support the view Such a course would have been by far the shortest, that Lourenço actually went so far as to make a small cheapest, and best way of disposing of one of the model of a fire-balloon rise in the air in presence important difficulties connected with aviation. But of the King of Portugal. Of pictures of Lourenço's what chance of success would a mathematician have protesque and fantastic design we have two in the if he made an appeal of this kind? The world is full number in question, but in No. 10 of Ila it is pointed of people who have made, or imagine they have out that if Gusman really did Ay, his ship must cer- made, epoch-making discoveries, and who only retainly have looked quite different.
quire funds for their development. Their effusions Another article dealing with the general history of find their way into every journal that does not adopt aërial navigation, both past and present, forms the the most strict censorship over the scientific value subject of a special number of La Nature, issued on of its contributions. The time has passed when any