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Prof. EWING'S MODEL.

BIBLIOTHECA CHEMICO-MATHEMATICA

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Being No. 650 of Sotheran's Price Current of Literature, Consisting of early and important Works on Mathematics, Astronomy, Physics, and Chemistry, with a Collection of more recent Works, Publications of Learned Societies, and Sets of Periodicals on the Exact Sciences ; and an Appendix

of Standard Works, English and Foreign. A large portion of the above Catalogue consists of an interesting Scientific Library formed in the early Eighteenth Century, and the Books in nearly all instances bear the fine armorial Book plate of the original noble owner. The other portion, chiefly Chemical, formed the Library of the late PROF. ALEXANDER WILLIAM WILLIAMSON, F.R.S.

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order in terms of initial values, and Prof. L. Wayland theory of corresponding states, and Dr. Onnes points out Dowling discusses the conformal representation of triangles, that further researches at low temperatures are required for with special reference to cases in which the solution can be the problems of the mechanism of the atom that have been represented by hyperelliptic integrals of given deficiency. forced upon us by recent discoveries. Dr. Onnes emphaIn a contribution to the Berlin Sitzungsberichte (1904,

sises the very important work done by Dewar in rendering

such low temperature observations possible. lii.), read December 8, Prof. Leo Koenigsberger discusses the extension of the principle of energy to a system having “ MATHEMATICAL Progress in America ” forms the subject a kinetic potential of any order, and any number of vari- of Prof. Thomas B. Fiske's address to the American ables dependent and independent. The paper forms a con- Mathematical Society published in the Bulletin of the tinuation of Prof. Koenigsberger's researches the society for February. Prof. Fiske divides the history of dynamics of systems in which time, instead of being one pure mathematics in America into three periods, the first dimensional, may be of two or more dimensions.

extending up to the foundation of the Johns Hopkins Uni

versity in 1876, the second extending from 1876 to 1891, PROF. GARBASSO has published a short note (Genoa,

when the New York Mathematical Society was converted Angelo Ciminago, 1904) in which he proposes a new theory into the present American Mathematical Society and began to account for the duplication of lines in the spectra of to issue the Bulletin, and the third covering recent times. variable stars. According to this theory, it is assumed that The Bulletin contains, further, the continuation of the rethe phenomena are due to the presence of an element the

port on last summer's congress at Heidelberg by Dr. E. B. atoms of which are formed of two separate conductors, and

Wilson, and a report of the meeting of the Deutsche Mathethat these atoms are mostly in a state of dissociation. The

matiker Vereinigung by Mr. R. E. Wilson. The Bulletin paper consists of a mathematical investigation of the

thus furnishes a summary of mathematical progress of a periods of a system of electric oscillators forming a model

cosmopolitan character such as does not exist in this of the supposed atoms.

country. IN 1890 a paper was presented to the Lincei Academy by Of the increasing attention which is being devoted on Prof. Filippo Keller entitled “ An itinerary guide to the the Continent to the history of the sciences, and in particular principal magnetic rocks of Latium," of which only an to that of mathematics, abundant proof is afforded by vol. abstract was printed. Since Prof. Keller's death in 1903 xii. of the Atti of the International Congress of Historical the complete paper has been brought out by Dr. G. Fol. Sciences, which met in Rome in April, 1903. This volume gheraiter as No. 11 of his series of Frammenti dealing is devoted entirely to the proceedings of the section which with the geophysics of the environs of Rome. It is ac- dealt with the history of mathematical, physical, natural, companied by a map of the district and a portrait and bio- and medical sciences, and it occupies 330 pages. It includes graphical notice of Keller, the latter by Prof. S. Günther. general discussions by Prof. Elia Millosevich on the iconIt is printed by Panetto and Petrelli, of Spoleto,

ography of solar eclipses, by M. Paul Tannery dealing with THE Revue générale des Sciences for February 28 con

proposals for advancing the history of science, some remarks tains a reprint of the paper read at Breslau by Dr. A.

by Messrs. D. Barduzzi, P. Giacosa, and Gino Loria on Kohler (Jena) on photomicrography by ultra-violet-light. It is

the introduction of university courses on history of sciences, illustrated by figures showing the arrangement of the micro

and proposals by Prof. Gino Loria for the publication of scope and camera, and the illuminating apparatus. It is Torricelli's works, and by Prof. Pietro Giacosa for a catapointed out that, independently of the increase of resolving logue of the scientific manuscripts in Italian libraries and power, ultra-violet light often affords a method of differ- archives. Among the papers read, the two mathematicians entiating between organic tissues in virtue of their different

associated with the solution of the cubic, Tartaglia and degrees of transparency to the rays, and, further, it in Cardan, receive mention at the hands of Mr. Tonni-Bazza some cases can be used to excite interesting phenomena of life of Bolyai ; Prof. A. von Braunmühl contributes an

and Prof. Moritz Cantor; Prof. M. Darvai deals with the Aluorescence in microscopic objects.

interesting paper on the history of the integral calculus; The Atli dei Lincei, xiv. (1) 3, contains a short account Prof. R. Amalgià writes on early theories of the tides; of some experiments by Mr. Alessandro Artom on wireless Prof. Icilio Guareschi on the alleged plagiarisms of telegraphy with the use of circular or elliptically polarised Lavoisier. Altogether the volume contains no less than waves. The experiments were divided into four groups, thirty-four papers. and in every case established the predicted property that it

ATTENTION has already been directed to the important would be possible to send methods in definite directions by the use of these waves. Thus, in the last series of experi

series of papers on applied mathematics now being issued ments, signals were sent from Monte Mario (Rome) to the by Prof. Karl Pearson, F.R.S., under the title “ Drapers' island of Maddalena without any effects being noticed at

Company Research Memoirs." Two further numbers have

now reached us. One of them is the fourteenth of Prof. the island of Ponza, which is situated some way off the line

Pearson's mathematical contributions to the theory of evojoining the first two stations. Further, it appears that with

lution, and deals with skew correlation and non-linear rethe use of circular waves the height of the aërial conductors can be reduced.

gression. The highly specialised character of the work may

be inferred by quoting one of four conclusions on p. 53 : The ninth supplement to the present series of Communi-“ The correlation between auricular height of head and age cation: from the Physical Laboratory of the University of in girls is cubical, of nomic heteroscedasticity and of Leyden contains an address delivered in commemoration of anomic heteroclisy. It is probably really a case of isocurthe 329th anniversary of the University of Leyden by Dr. tosis." The other paper is by Mr. L. W. Atcherley and H. Kamerlingh Onnes, Rector Magnificus of the university. Prof. Pearson, and deals with the graphics of metal arches. It deals with the importance of accurate measurements at

In it the authors point out the impossibility of applying very low temperatures, a need which, it is pointed out, was purely graphical constructions with any degree of accuracy first appreciated by Boyle. An important application of such to the very flat metal arches used in modern bridges, and observations has arisen in connection with van der Waals's I they propose a kind of “ semi-graphical" method, depend

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now

ing partly on analysis and partly on graphics. Some in- shortened. The appendices have been considerably altered teresting conclusions are drawn as to the relative merits of In the preface to the new edition Prof. Schlich directs doubly pivoted, three pivoted, and doubly built in arches. attention to the fact that the most urgent need of British These memoirs are rendered more accessible by being issued forestry is the collection of statistics, which will enable with their pages cut. They show what a lot of good work the proprietor and his forester to gauge the economic value may be done by the expenditure by a public body of a very of forest operations. He insists that the fully equipped moderate sum on the endowment of mathematical research. forester must have a good knowledge of mathematics if he We have another example of the same fact in the Cam- is to secure the best results. bridge Smith's prizes and the large number of former

A new encyclopædia, prepared and printed by Messrs. winners of these prizes who are now Fellows of the Royal

T. Nelson and Sons, is to be published in forty fortnigbtly Society.

parts under the title of the Harmsworth Encyclopædia." The widely extended use of the freezing point and boil- Three of these parts, each of 160 pages, have been re ing point methods of molecular weight determination has ceived, and judging from these we do not hesitate to say been to a large extent rendered possible by the manufac- that the complete work should be a useful aid to students

of sensitive thermometers of the familiar and a responsive friend to general readers. So far as we Beckmann type. In the current number of the Zeitschrift have tested the parts received, we have found the informfür physikalische Chemie is a very interesting paper by

ation accurate and confined to essential points. Of course, Mr. Ernst Beckmann giving a complete history of the

it must be understood that within the limited space allotted differential mercury thermometer, with especial reference to any subject only bare outlines can be described ; but as to the modifications it has undergone since its first use in references are in many cases given to authoritative works, freezing point work. He mentions the fact that the inquiring readers may be led to pursue their search for original Beckmann thermometer was due to an accident. information, inspired by what they find in this encyclo A costly instrument, divided into 1/100ths of a degree, was pædia. The work is liberally illustrated, and as a conbeing carried in the hand down a corridor when it was venient guide to information which men and women often broken in half by the sudden opening of a door. In order seek to know it will be of service. still to be able to use the thermometer, a small bulb was blown on above the capillary, and from this the present

OUR ASTRONOMICAL COLUMN. type was evolved through a series of instruments illustrated

ASTRONOMICAL OCCURRENCES IN APRIL:in the present paper. Some of the thermometers figured April 4. 2h. Mercury at greatest elongation (199 'E. are masterpieces of glass-blowing, notably one combining

5 23h. Mercury in conjunction with the Moon. a Beckmann and ordinary thermometer on one instrument.

(Mercury 7° 28' N.).

6. 6h. Jupiter in conjunction with Moon. (Jupiter Messrs. JOHN WHELDON AND Co. have sent us their

3° 35' N.). latest catalogue of scientific books they have for sale. The 9.

h. 4m.

Minimum of Algol (B Persei). catalogue includes many sets of Journals and

7h. 53m.

Minimum of Algol (B Persei) Transactions, as well as selections from the libraries of

15. Venus.

Illuminated poriion of disc =0'049 : of

Mars=0*975. the late Prof. Everett, Dr. C. W. Siemens, and others.

17.

Sh. 18m. to gh. 12m. Moon occults Virginis

(mag. 4'0). The most recent addition to the report being issued by 20-22. Epuch ol Lyrid meteors (Radiant 271° +33°). the Engineering Standards Committee is the “ British

DiscoveRY OF A New COMET, 1905 a.--A telegram from Standard Specification and Sections of Flat-bottomed Rail- the Kiel Centralstelle announces the discovery of another way Rails.” Copies of the publication may be obtained new comet by M. Giacobini. at Nice on March 26. from Messrs. Crosby Lockwood and Son. The price is The position of the comet at Sh. 11.8m. (M.T. Vice ros. 6d. net.

was R.A. = 5h. 44m. 148., dec. + 10° 56' 36", and its

daily movement in R.A. = + 3m., in dec. – 1° 15'. We have received from Mr. Nasarvanji J. Readymoney, This shows the object to be in the constellation Orion. of Bombay, a copy of a publication he has prepared en

about 6m. W. and 3° 34' N. of Betelgeuse, or a little titled An Outline of Descriptive, Defining Nature-History S Geminorum, along a straight line joining the two

more than one-fourth the distance from Betelgeuse tu Tables, Illustrated; or Nature-History Research Thinking Apparently the comet passed very near to Betelgeuse en Tables; or Work of Genesis Minutely Tabulated." The

March 29. object of the tables is to enable the student to summarise

COMET 1904 e (BORRELLY).-A continuation of the daily and classify all events in nature or creation ” in a philo- ephemeris for comet 1904 e is given by Dr. E. Strömgren sophical manner.

in No. 4004 of the Astronomische Nachrichten.

The ephemeris extends from March 29 to May 4, and The February number of the Journal of the Straits from it we see that on the first named date the conut Branch of the Royal Asiatic Society has reached us from will apparently be situated very near to Auriga, and Singapore. Among other important papers we notice con

will have a brightness of 0-24. Travelling thence in an tributions by Dr. Charles Hose on various methods of

E.N.E. direction it will enter the constellation Lynx, its computing the time for planting among the races of

computed position on May 4 being R.A. = 7h. Och...

dec. = + 45° 17', whilst its brightness on that date will be Borneo, by Mr. P. Cameron on descriptions of new species The brightness at time of discovery (about mag. toi of Iphiaulax and Chaolta (Braconidae) from Sarawak,

is taken as unity. Borneo, and by Mr. H. W. Firmstone on Chinese names OBSERVATIONS OF THE RECENT ECLIPSE OF THE Moos.of streets and places in Singapore and the Malay Peninsula. In No. 9 (1905) of the Comptes rendus is published a paper

by M. Puiseux wherein he discusses a series of twelve A New and revised edition of the volume of Prof. W. photographs taken between 7h. 32m. and Sh. 12m. on the Schlich's “Manual of Forestry " dealing with forest occasion of the partial lunar eclipse which occurred ca

February 19. management has been published by Messrs. Bradbury,

Amongst other conclusions he states that the apparent Agnew and Co., Ltd. The mathematical problems have changes in the aspects of the circles Messier and Messier A been simplified, and some of the calculations have been | are simply due to differences of illumination and not to

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actual variations, and that, whilst the recent observations

THE U.S. COAST AND GEODETIC SURVEY. of these two circles and of Linné are not in accordance with the records obtained prior to 1866. thereasures subh The report of the Coast, and Geodetic Survey, for which as have been announced by several selenographers. M. have for their theatre of action an area practically coterPuiseux believes that many of the circles are undoubtedly minous with that of the United States and all its island of later origin than certain systems of divergent streaks possessions. The main body of the report contains a seen on the lunar surface.

detailed account of the wide range of duties devolving

upon this bureau, and in the appendices we have a preNew VARIABLE STARS IN THE REGION ABOUT 8 AQUILÆ.- sentation of discussions and results which must prove of In No. 4005 of the Astronomische Nachrichten Prof. Wolf great economic value and interest to surveyors, engineers, publishes a list of thirty-six newly discovered variable stars navigators, and physicists. in the region about 8 Aquilæ. Their variability was de- The re-surveys and developments imperatively required tected by the comparison of two plates taken with the to show the changes in harbours and approaches due to Bruce telescope on July 12, 1902, and July 6, 1904, re- works of improvement or the ceaseless action of natural spectively. The positions (1875.0) of the new variables are causes along the Atlantic, Pacific, and Gulf coasts of the given in the catalogue, and, together with the positions United States, and to meet the ever-increasing demands of of four others which are also probably variable, are shown commerce and the Navy for up-to-date charts, particularly on thirty-two circular charts accompanying the paper, each of the waters of Alaska, Porto Rico, Hawaii, and the chart including a field twenty-one minutes of arc in

Philippines, gave constant employment to the eleven vessels diameter. In a second table the magnitudes of the stars available for these duties. on the two plates mentioned above are compared with the In Alaska the work included the continuation of the magnitudes as shown on a third plate taken on August ii, survey of Prince William Sound, the survey of Con1898.

troller Bay, and a deep-sea examination from the Strait

of Juan de Fuca to Prince William Sound, preliminary to ORBIT OF THE BINARY STAR CETI 82.–The orbit of the

the laying of a deep-sea cable from Seattle to Valdez. The binary star Ceti 82 (designated 395 in Prof. Burnham's Porto Rico work was continued in certain bays and catalogue) is discussed by Prof. Aitken in Bulletin No.

harbours as well as in the development of the conditions 71 of the Lick Observatory.

in the off-shore waters. In the Philippine Archipelago The Lick observations confirmed the rapid orbital

the Survey has secured the cooperation of the Insular motion, but have also indicated a very different orbit from Government, and a detailed résumé shows a most satisthat previously · published by Prof. See (Astronomische Nachrichten, vol. cxliv., p. 359, 1897).

factory progress of the triangulation, hydrographic, topoThe elements obtained by Prof. Aitken show a period of

graphic, magnetic, and astronomical operations.

The reconnaissance for the primary triangulation along 24.0 years, and give the G.M.T. of periastron passage (T) the 98th meridian was completed to the Canadian border, as 1899-7. The elliptical orbit is graphically presented, and and a scheme was extended eastward connecting this work shows the differences between the observed and computed

with the triangulation of the Mississippi River Commission. places. The eccentricity of the ellipse is 0.15, and the The execution of the primary triangulation in the Dakotas apparent length of its semi-major axis 0".66 of arc. Prof. Aitken also gives an ephemeris extending from 1905-7 to

and Texas was prosecuted at a rate which surpassed even

the notable record which had already secured an enviable 1910.7.

reputation for the geodetic operations along the 98th RADIAL VELOCITIES OF CERTAIN STARs.-In No. 70 of the

meridian, the total extension amounting to 300 miles Lick Observatory Bulletins Prof. Campbell and Dr. H. D.

(500 kilometres). An equal distinction must be accredited Curtis discuss the radial velocities of Polaris, m Piscium,

to similar work in California and Oregon, whereon remark

able progress has been made in connecting the Trans€ Aurigæ, and Rigel from the spectrograms obtained at

continental Arc work with Puget Sound. Lick during the last eight years.

The progress of the magnetic work shown in detail In the case of Polaris, the measurement of groups of in Appendix No. 3, which includes a table of results of the plates taken during the last four years indicated that the velocity of the centre of mass of the rapid pair in this

magnetic declinations, dip and intensity of force observed

on land and sea during the year, this being supplemented triple system is changing very regularly with a period of with full descriptions of the magnetic stations occupied at least eleven or twelve years, but the period may be and meridian lines observed. (This report has been noticed found to be much longer when further observations are

separately, NATURE, March 9, p. 449.) completed.

The determination of the longitude of Manila from San The radial velocity of 7 Piscium was suspected by Prof. Lord to be variable with a long period, but as no spectro

Francisco, thus completing the first longitude circuit of

the earth, was one of the astronomical events of the year, grams of this star were secured at Lick during the period and in Appendix No. 4 is a comprehensive illustrated report covered by him, the Lick observations do not settle the

on the various instruments and operations used in the question, although the values obtained only range from

undertaking, with a comparative résumé of the various + 16.6 to 13:3 km. per second, whilst Prof. Lord's range links and results from which the longitude of Manila had was from +9.5 to 25.4 km.

been determined from the westward. The generous coThe spectrograms obtained of € Auriga fully confirm operation of the Commercial Cable Company, through the Prof. Vogel's conclusion that this star is a spectroscopic patriotic enterprise of which the work was made feasible, is binary with a period of several years. Prof. Vogel's view that Rigel has a variable radial

gratefully acknowledged. The results of the determinations

from the eastward and westward differ only by 0.006s., or velocity is not confirmed by the Lick observers, who rather about 8.8 feet. The other results of this expedition are favour the conclusion arrived at by Profs. Frost and the determinations by the telegraph method of the longiAdams that the apparent variation is only a function of the tudes of Honolulu and Midway and Guam Islands. difficulty experienced in measuring the wide lines.

The third attempt at representing the tide for the world

at large, the first having been made by Whewell and STAR PLACES IN THE VULPECULA CLUSTER.-In No. 4004 Airy and the second by Berghaus, is described in Appendix of the Astronomische Nachrichten Dr. H. Meyer gives a No. 5. The advancement in recent years of the general catalogue of the positions of thirty-five stars in the use of the harmonic analysis, and the greatly improved Vulpecula cluster. The catalogue contains the B.D. tidal data that are now obtainable for such a great part number, the magnitude, and the positions, the latter re- of the globe, coordinate to make a new presentation of this ferred to the equinox of 1900 o for the epoch of observ- subject very opportune. The theoretical discussion of the ation 1901.6. The precession and the secular variation in problems involved, the wide range of data and authorities each coordinate are also given for each star, and in the consulted and referred to, the graphic presentation of the case of fourteen of the brighter ones the proper motion, cotidal lines, the results presented, and the conclusions as determined from the discussion of previous catalogues, deduced, make a most suggestive paper, and one which is likewise given.

will be highly interesting to all students of the subject.

The results of the precise levelling operations for the especially amongst the Lepidoptera and Orthoptera, to year are published in Appendices Nos. 6 and 7, which leaves, twigs, moss, &c.; and a number of illustrations are submit them in a detail that makes them immediately given of resemblance to natural surroundings, three of available for the requirements of surveyors and engineers. which we select as examples. These extend the precise level net, as previously published, six hundred miles to the westward, from Red Desert, Wyoming, to Owyhee, in eastern Idaho, and from Holland, Texas, two hundred miles south-west, to Seguin, Texas. An interesting feature is an account of the change in the manner of support for the levelling rods, with the comparative discussion of the old and the new methods, and the consequent confirmation of the importance of the new system.

The account of operations submitted by the assistant in charge gives the story of the work of the various computing, drawing, engraving, and chart divisions of the office in which the results of the field work are discussed or prepared for the publications and charts wherein they are placed at the service of the public.

A full account of the first recording transit micrometer devised for use in the telegraphic longitude determinations of the Coast and Geodetic Survey is submitted in Appendix No. 8, with an account of the exhaustive tests it was subjected to, and a recapitulation of the results of experience with this form of instrument, mainly in Europe, during the last thirteen years. The results of these experiments indicate that with the transit micrometer the accuracy of telegraphic longitudes may be considerably increased if desirable, or the present standard of accuracy may be maintained at much less cost than formerly.

The results of all triangulation in California south of the latitude of Menterey Bay are printed in the concluding appendix in full,' including descriptions of stations as well as their latitudes and longitudes and the lengths and azimuths of the lines joining them. In compact and

Fig. 1.-Embusa gongylodes (Ceylon) at rest on iwi convenient form there is given all the information in regard to this triangulation that is needed by an engineer or surveyor who wishes to utilise the results in controlling

Among the many curious and interesting insects which and checking surveys or in constructing maps or charts.

are found in Ceylon, Empusa gongylodes is one of the most The locations of more than 1300 points are accurately

singular. It is a brown insect. The thorax is like a long fixed by this triangulation.

The report, in addition to the details of the foregoing operations and results, contains a record of a wide range of important work for which the aid of the Survey was sought because of the special training of its officers.

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PROTECTIVE RESEMBLANCE.
AN interesting paper on Protective Resemblance in the

Insecta," by Mr. Mark L. Sykes, is published in the Proceedings of the Manchester Field Club (vol. i., part ii). After briefly describing the law of natural selection, as propounded by Darwin, the evolution of new species through variations, and the elimination of the least fit during long periods of time, reference is made to the colours of insects, to the advantage of conspicuous adornment, and the consequent easy identification of those of them which possess some feature repellent to the insecteating animals. The absence in young animals of an intuitive faculty of discrimination between edible and inedible material in the selection of food is emphasised, and reference is made to authors who have experimented on the subject.

Müller's theory of mutual protection, through similarity of colours and patterns, amongst inedible Lepidoptera, and Bates's explanation of the “ mimicry " or simulation of distasteful species by edible species, are described, and the superficial resemblances between entirely different species and genera are attributed to the influence of natural selection and elimination, and the transmission and accumulation of variations. The method by which many of these likenesses are produced is shown by a number of camera lucida drawings of the wing scales of many of the butterflies and moths referred to and illustrated in the article ;

Fig. 2.- Eurybrachis Westwoodit (Ceylon) with the wings expanded, 250 and the scale variations, in colour, size, pattern and ar

at rest upon a piece of bark. rangement, which produce a common resemblance in the thin twig, with a wide leaf-like expansion immediately insects, are described. Another branch of the subject, behind the head. The wings are broad, veined and treated in some detail, is protective resemblance of environ. crumpled, like dried leaves, and the long legs, which are ment, as seen in the striking similarity of many insects, spread out in any direction as the animal is at rest, har

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