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likely to survive and to perpetuate dark forms. Mr. parthenogenetically it would produce no offspring like Porritt did not believe that birds fed to any great extent itself. An experiment for testing this theory in an inon moths, and when they did they took them on the wing dividual case was described. at night, when their colour similarity to trees would be of no service. Moreover, many melanic species do not

Mr. J. T. Cunningham spoke on the evolution of the affect tree trunks, e.g. Larentia multistrigaria, in which cock's comb; Mr. H. M. Bernard, on a periodic law in melanism has rapidly developed for no apparent reason.

organic evolution, with a re-estimation of the cell ; and The theory that smoke and humidity in the manufacturing Dr. H. J. Fleure and Miss Galloway gave a detailed paper districts have caused melanism, although offering in many

on the habits of the Galatheidæ in relation to their struccases a likely explanation, seems to be rendered untenable

ture; but these and a few other papers do not lend themby numerous exceptions. Mr. Doncaster remarked that selves to the purposes of a summary. inelanism could not be explained as due to natural selec

J. H. Ashworth. tion or as the result of external conditions, as the black forms in some cases arose suddenly, and quickly became numerous. The black form is dominant, that is, the off

THE ROYAL PHOTOGRAPHIC SOCIETY'S spring of a pair, one black and one pale, have a tendency

ANNUAL EXHIBITION. to be dark. Dr. Dixey pointed out that in Pierines dark This exhibition at the New Gallery in Regent Street pigment is often substituted for light, the female being will remain open until October 27. The three rooms, usually darker. There may even be two grades of colour the central court, and the balcony, indicate its five main in the females, a darker in the individuals found in the divisions. The last of these is devoted to scientific and wet season, and a lighter in those found in the dry season. technical photography and its application to processes of He considered that locality, altitude, and other conditions reproduction, and the exhibits here naturally fall into three may have an influence in darkening the pigment.

sections, namely, the ordinary exhibits, those contributed

by special invitation of the council of the society, and a Pineal Eye of Geotria and Sphenodon.

small collection of photographs that have no other interest Prof. Dendy described the structure of the pineal eye

than that they are good technical work, and represent of the New Zealand lamprey (Geotria), which agrees in

subjects of or less interest, chiefly architectural. most respects with that of Petromyzon, but the former is

We hope to see this kind of work more fully represented more complex in histological structure, its pigment cells

in future exhibitions, for between the more strictly techbeing divided into inner and outer segments. The pineal nical and the ultra-pictorial it has been almost squeezed nerve is connected both with the right habenular ganglion

out of existence. and the posterior commissure, and in all probability with

A series of beautifully made models of light-pencils, Reissner's fibre, whereby it would become linked with the

which show the various effects of aberrations that paroptic reflex apparatus described by Sargent. Prof. Dendy ticularly concern photographic lenses, is shown by Mr. also directed attention to some newly observed details of

C. Welborne Piper, and has been awarded a medal. The structure in the adult pineal eye of Sphenodon. The rods of

three dozen models illustrate very clearly a subject that the retina project into the cavity of the eye, and are con

must always be a somewhat difficult one. Immediately nected with a network of fibres, which is also connected following this are a large number of photographs of living with the " lens." The lens contains a large central things, but chiefly birds, which appear to be receiving å cell which resembles a unipolar ganglion cell. Prof. Dendy very undue share of attention just now. Of these, we concluded that, in both Geotria and Sphenodon, the pineal notice particularly a series of twenty-four photographs of pye is a functional organ.

the stone curlew in different stages of its existence, by Mr.

W. Farren. Of the other subjects, “A Study of Wych Formation of Nucleoli.

Elms,” by Mr. Alfred W. Dennis, is among the more novel. Prof. Havet (Louvain) traced the formation of true

It is a series of seven photographs that show the same nucleoli or plasmosomes in the nerve cells and blood cells pair of trees, leafless and in leaf, and on larger scales the

details of the trunk, blossom, fruit, leaves, and winter of Rana and Alytes. The central part of each is formed

buds. Dr. Vaughan Cornish sends a further series of from a small, clear area situated in the centre of the

waves; Mr. J. Č. Burrow two coal-mine subjects, excelfelophasic figure, while the peripheral part is derived from the internal extremities of the chromosomes which remain lently rendered as usual ; and Mr. Bagot Molesworth a

telephotograph of Vesuvius in eruption, taken from when the rest of the chromosomes form the nuclear net

distance of eight miles. work. Occasionally chromosomes also become included in

In the invitation section, Mr. Douglas English shows the central area, giving rise there to one or two chromatic

some examples of mimicry in British insects, and a parstructures.

ticularly realistic effect is obtained in some of them by Milk Dentition of the Primitive Elephant.

making the original carbon print with a green tissue, and

staining the insects with dyes to represent their natural Dr. C. W. Andrews, in the course of a paper on the colours. The Royal Observatory, Greenwich, has conmilk dentition of the primitive elephant, pointed out that tributed several of its recent results, including some of in recent elephants, owing to the large size of the molars

last year's solar eclipse. Mr. F. E. Baxandall (for Sir and the shortening of the jaws, the teeth have an almost Norman Lockyer) also illustrates the eclipse, and sends horizontal succession, their manner of replacement differing photographs of two British stone circles that were erected widely from the vertical succession found in other mammals.

some four thousand years ago as astronomical obseryBut as the earlier relatives of the elephant are followed

atories. Series of cloud photographs are shown by Dr. back through the various Tertiary horizons a gradual W. J. S. Lockyer and Captain D. Wilson-Barker. Photoapproximation to the ordinary mammalian type of tooth graphs illustrating the investigation of crimes, such as replacement is observed, until in the recently discovered | forgery and burglary, and the detection of the criminals, Eocene Palæomastodon a form is reached in which the by Prof. R. A. Reiss, of Lausanne, will be of very milk molars are replaced in the normal way by premolars, general interest. Mr. K. J. Tarrant shows a series of which, along with the permanent olars, remain in use

thirty photographs of high-tension electrical discharges. throughout the life of the animal.

Mr. Edgar Senior has continued his study of the Lipp

mann method of colour photography, and although the A New Conception of Segregation.

image generally shows no grain under the microscope, he Mr. A. D. Darbishire directed attention to some essential has by special illumination got the surface to appear but usually unrecognised features of the Mendelian theory. covered with discs of light, though what these indicate is He pointed out that although half the total number of not very clear. children born to hybrids were unlike their parents, the There are a few photographs in “ natural colours,” but hybrids, according to that theory, bore no single germ nothing better than, if quite so good as, has already been cell containing an element representing an animal like shown. Messrs. Sanger-Shepherd and Co., by preparing a themselves, and that if a hybrid could be made to multiply more rapid and red-sensitive plate and special colour filters,

a not

have made it possible to take the three negatives necessary was each 80 feet, but two others of 160 feet and 320 feet for their method of colour photography in three seconds, in respectively were used in crossing streams and gulleys. cluding the time required for changing the plates and Another form of the same apparatus, occasionally used, light filters, when the light is only moderate and the lens consisted of a wire of “invar" nickel-steel and a wire of aperture f/ 16. In the central court, besides a great deal another alloy having a coefficient of expansion about the of apparatus and several demonstrations of processes, the same as that of brass. The absolute length of each of Adhesive Dry Mounting Co. shows its method of mount- these pairs was determined by repeated comparisons with ing by warm pressure. The Ozotype Co. shows in the a base line 80 feet in length, measured with a standard north room several examples of " ozobrome prints. These bar apparatus ; but even the length of this base could not are quite a new departure, a carbon print being produced be assumed to be constant. The partially decomposed by means of a bromide print without exposure to light, quartzose slate beneath the piers which carried the fiduciai the silver image in the bromide print reducing the marks appeared to change slightly in position, especialis bichromate in the carbon tissue by mere contact. The after rain, and the length of this base as measured in the original bromide prints and the carbon copies are shown wet and dry seasons differed by half a millimetre. Constant side by side.

C. J.

measurement with the bars removed any source of error from this cause, since the change of length between the

beginning and end of a set of wire comparisons was GEODETIC OPERATIONS IN SOUTH AFRICA.. practically insensible.

But the real source of error in the use of the Jäderin IT T will be admitted that the Administration of Southern Rhodesia acted wisely in accepting the timely counsel

wires lies in the fact that the ordinary steel and brass which Sir David Gill brought under its consideration.

wires are liable to change of length, due to re-arrangement Some ten years ago His Majesty's Astronomer at the Cape independent of temperature after these molecules have been

of the molecules of the constituent metals which takes place pointed out to Lord Grey, who then administered the government of the colony, the desirability of basing the

violently disturbed. The tendency in all new drawn wire land tenure on a properly established system of survey.

is to shorten, very markedly at first, and to diminish in The adoption of such a course would not only afford the

amount as a more stable arrangement of the molecules in means of supplying a sound and incontrovertible evidence

established. In a postscript, however, it is stated that, as of title to the possessor, but would protect the Government

the result of experiments conducted at the International against the perpetration of fraud and tend to diminish

Bureau of Weights and Measures, it is found possible buv future litigation. Sir David Gill does not hesitate to say

careful annealing and special mechanical treatment that in Cape Colony large tracts of land have been stolen

render the arrangement of the constituent molecules as from the Government, either through the wilful shifting of

“invar" wires practically stable, and that such wires can beacon marks or from carelessness due to inadequate

be used as standards. Such wires, however, are surveying. Sir David Gill did not lay any great stress

examined here. As an evidence of the change of length in upon the scientific value that necessarily attaches to accurate

the wires actually used, we may quote the following: measurement conducted on a large scale ; but this point

The length of a standard pair, at a temperature when both was not neglected, and the work was planned so as to components were of equal length, was found to be in give the greatest assistance to economic requirements, and

April and May, 1898

24382-07 mm. at the same time to forward scientific interests. The one

October and November, 1898 24381.84 purpose was effected by carrying a chain of triangles east

Two base lines were measured in the course of the work, wards from Bulawayo, covering the most thickly populated

one of us miles and the other of 133 miles. The first, and important parts of the country, the other by extending

known as the Inseza base, was measured in three sections, the chain north and south along the thirtieth meridian, so

the second in seven, each section being measured in opp that it might form part of the great arc of meridian which

site directions. As an indication of the accuracy attained it is proposed to extend from the south of Natal to the

we give the repeated measures in the shorter base :Mediterranean. The actual district surveyed extends from about 16° to 20° south latitude and from 28° to 31° east


Reverse Discordance longitude.

Sir David Gill sketches the history of the work accomplished in successive years, from which can be gathered Length of Section 1. 4,509.571 88 4,509,554-47 i in 259.000 something of the difficulties which Mr. Simms and his

II. 6.200, 765.86 6,200,732181,. 184.000 assistants encountered and

Abnormally wet

III. 8,196,927 19 8.196,928.28 1., 4.746,000 seasons, illness among the staff, the necessary burning of the grass and the rising of the smoke preventing the measure


18,907,264 '93 18,907,214'93 1 in 378,000 ment of horizontal angles, loss of cattle, and in one instance the destruction of the theodolite, are a few of the troubles that beset those who attempted geodetic operations in an

We have not space to quote the results in the case of

the Gwibi or longer base, but the results there are even unsettled country; but, notwithstanding these drawbacks, there remained only three stations south of the Zambezi

more accordant, the average discrepancy amounting to onis one in a million and a half.

W. E. P. which were not fully connected with the scheme of triangulation proposed. As the work is extended northwards these stations will be occupied, and thus form a useful link in


INTELLIGENCE. A matter of great interest in the report from a scientific point of view consists in the critical examination of the

The celebration of the four hundredth anniversary of Jäderin wires used in the measurement of the base lines.

the foundation of the University of Aberdeen began on This apparently convenient form of measurement was, it is Tuesday, and will continue for several days. The cor believed, adopted by the Russian geodesists in the work

memoration has been planned on a magnificent scale, and connected with the Spitsbergen base, but in this country

the arrangements have been perfectly organised. Thr the apparatus has not been submitted to any very thorough

formal proceedings opened on Tuesday morning with test, and figures for the first time on a large scale in the

service at King's College in commemoration of the found. geodetic survey of South Africa. Two wires, one of steeling of the University by Bishop Elphinstone. In the afras. and the other of brass, constitute a

noon, at pair,” and, as a rule,

a reception given by the Chancellor (L484 were used in this form. Each wire is about 1.65 mm. in Strathcona) and other high officers of the University, the diameter, and is stretched by an accurate spring balance delegates of the British, colonial, and foreign universities with a tension of 10 kilograms. The length of three pairs

were presented to the Chancellor and delivered their

addresses. In the evening a banquet was given by the 1 Report of the Geodetic Survey of part of Southern Rhodesia executed

Lord Provost and the corporation. Among the distin. by Mr Alexander Simms, Government Surveyor, under the direction of Sir David Gill, KCB, F.R.S., His Majesty's Astronomer at the Cape.

guished foreigners who are taking part in the celebratings Pp. xiv + 146. (Cape Town, 1905.)

are :-Prof. H. Becquerel, Prof. Behring, Dr. C. Der



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Candolle, Prof. Deissmann, Prof. Yves Delage, Dr. Anton days, an industry that does not repose on a scientific basis Dohrn, Prof. A. Giard, Prof. H. Höffding, Prof. F. is one which has no proper knowledge of itself, science Hueppe, Prof. Jensen, Prof. Lombroso, Prof. Matsumura, being nothing more than organised systematic knowledge. Prof. Mendeléeff, Prof. Menschutkin, Prof. Hugo Münster- Scientific training, training in method, is required by all. berg, Prof. W. Ostwald, Prof. Giuseppe Veronese, Prof. Scientific knowledge, true knowledge, be public Paul Vinogradoff, Prof. J. W. Wijhe, and Prof. Weichselpossession. The feeling is becoming general that somebaum. The lecture-rooms, laboratories, and other buildings thing must be done to make our schools more effective which will be opened by the King to-day have cost than they are. In a recent report of the Consultative Commore than 200,000l. to erect and equip. The new block mittee, the Board of Education is advised that the schools completes the quadrangle, and includes new class-rooms have failed, in the past, to develop both the moral and and laboratories for physiology, geology, and agriculture ; mental qualities which are desirable, and that we must new rooms for education, medicine, modern languages, and now strive to make the teaching far more practical, manual other subjects ; a new library for scientific literature, and training being openly and strongly advocated. We read, new offices. We hope to give in our next number a de- moreover, It would seem clear to the committee that the scription of this extension of the University, and an account thing needed is not only knowledge, but a right attitude of the brilliant ceremonies with which it has been of mind, a mind confident in its own power to observe and inaugurated.

think, and in the habit of observing and thinking-a mind The next session of the South-Eastern Agricultural

in which interest makes for intelligence and intelligence College, Wye, will commence

". The course,

for interest.” October 1, and the

it is stated, “ should consist

of three threads inaugural address will be delivered by Dr. H. E. Arm

strands, roughly to be termed strong, F.R.S., on October 2. A conference of fruit

humanistic, scientific, and manual, and, in the case of growers will be held at the college on October 22, when

girls, domestic; all higher elementary schools should give discussions on methods of planting, fungus diseases, insect

this threefold instruction." Though these views have been attacks, strawberry culture, will be opened by Messrs. S. U.

urged by many educational reformers for thirty years or Pickering. F.R.S., E. C. Salmon, F. V. Theobald, and

more, the doctrine they involve is really quite revoluW. P. Wright. The chair will be taken by Mr. Laurence tionary, coming from such a quarter, especially as it is Hardy, M.P. Those wishing to attend the conference

directed to the Board of Education, which treats manual should send their names to the principal of the college.

training as a special subject for the select few. On October 11 Sir William Anson will distribute the prizes awarded to students in the evening classes of the Royal Technical Institute, Salford. The calendar of the

SOCIETIES AND ACADEMIES. institute for the session 1906–7 contains the announcement that all intending students under sixteen years of age will,

LONDON. before admission to the evening classes, be required to pass Royal Society, December 14, 1905. -"Observations on an entrance examination in elementary mathematics and the Development of Ornithorhynchus." By Prof. J. T. English, or to satisfy the principal that they possess the Wilson and Dr. J. P. Hill. Communicated by Sir William requisite preliminary knowledge. Those who do not

Turner, K.C.B., F.R.S. possess the knowledge necessary to pass the entrance The paper treats of certain stages in the intra-uterine examination are recommended to join one of the evening development of the egg of Ornithorhynchus. The following schools which have been instituted in various parts of are points of more special interest among those set forth Salford, and at which the required preparation is provided. in the extended paper :It is intended that next year all under seventeen years of (a) The very early differentiation of the layer of yolk. age shall furnish evidence of the possession of the requisite entoderm surrounding the yolk-mass of the monotreme preliminary knowledge.

egg. In the early days of the movement for the higher educa

(6) The original entire independence of the primitive tion of women, one of its most active workers was Mrs.

streak from the primitive knot and its gastrulationWilliam Grey, whose death on September 19

at the cavity." advanced age of ninety years was announced in the Times

(c) The subsequent intimate approximation of these strucof September 21. Mrs. Grey's name was from the first tures. well known among those who advocated and carried to a (d) The early appearance of an area of special differentisuccessful result the foundation of high schools for girls ation in the vicinity of the primitive streak in the early by, combined private effort; and the Girls' Public Day blastoderm, and the later conversion of this “ primitiveSchool Company (Ltd.) was the outcome of this move

streak-area " into an embryonic area

proper, by the ment. Springing out of the needs presently revealed by

annexation of the region surrounding the primitive ” or the high schools came the establishment of a system of

“ archenteric knot. training for secondary teachers. The idea was then com- (e) The precise mode of disappearance of the ventral paratively new in England, and public opinion on the

wall or floor of the archenteric- or invagination-cavity. subject had to be formed and fostered, as it was largely

) The occurrence of peculiar segmental cell-masses in through the work of Mrs. Grey. In recognition of her

the substance of the “ primitive knot,” where that conlabours the well-known Maria Grey Training College for

stitutes the parietes of an archenteric canal or its repreWomen, now situated at Brondesbury, was named after


(g) The diagrammatically clear demonstration of various

features of neural development, including the well-marked An inspiring address on educational methods and their neuromeric segmentation of the cephalic region of the relation to science and industry, with particular reference flattened medullary plate, the differentiation of early plateto pottery, was delivered by Prof. H. E. Armstrong in the like ganglionic expansions of the neural crest in the Town Hall, Longton, on September 19. In the course of cephalic region, the presence of various cellular connections his remarks, he said that workers in science have evolved between the cephalic ganglionic plates and certain of the & method, the scientific method, involving the gradual and neuromeric segments of the medullary plate. cautious passage from the known the unknown.

(h) The relative insignificance of the “ archencephalic" Workers in politics have no such method at their disposal. subdivision of the cephalic portion of the medullary plate, Too often they are more or less ignorant of the real nature from which the fore-brain and most, if not all, of the midand extent of the problems which they deal with and seek brain are derived. to solve ; sentiment masters their actions. The application of scientific method to public affairs is, consequently, be- June 28.-" Vote the Production of Secondary coming a matter of paramount importance. In all manu- Rays by a Rays from Polonium." By W. H. Logeman. facturing districts science and industry must be brought Communicated by Prof. J. J. Thomson, F.R.S. into an effective alliance. On no other basis are prosperity The author describes results which were obtained in the and happiness possible, for the simple reason that, in these course of some experiments on the slowly-moving negative





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or 8 rays emitted by polonium, and which indicate that re-calculation.-The action of fluorine on chlorine, and on negatively charged secondary rays are produced when an new method of formation of hypochlorous acid : Paul aluminium or copper plate is bombarded by a stream of Lebeau. Attempts were made to combine fluorine with a rays.

chlorine, under varying conditions, at temperatures ranging The method used may be briefly described as follows :- from 0° C. to –80° C. It was found that fluorine ani A polonium-coated copper disc was placed in a glass tube chlorine do not combine directly. Liquid chlorine diswith its active side facing, and parallel to,

highly in

solves fluorine, but this fluorine is given off at the solidifysulated metal disc of the same size, which could be con- ing point of the chlorine. In presence of water, fluorine nected to one pair of quadrants of a sensitive Dolezalek oxidises chlorine, the latter being completely converted into electrometer. The distance between the discs could be hypochlorous acid, thus giving a new method for the preadjusted. The polonium disc could be raised to any paration of this acid.-Syntheses in the quinoline group required potential by connecting it to a battery of small phenylnaphthoquinoline dicarboxylic acid and its deri. secondary cells. The glass tube was evacuated by means vatives : L. J. Simon and Ch. Mauguin.-The action of of a mercury pump down to a pressure of about 0.001 mm. mixed organomagnesium compounds upon amides : Conand then sealed off, and the vacuum was then rendered stantin Béis. To secure a reaction in all cases it is neces. as high as possible by the use of Dewar's method. The

sary to prepare the organomagnesium compound in the apparatus was placed between the poles of an electro

presence of the imide, the alkyl halide being added to a magnet in such a manner that a magnetic field could be mixture of the imide, magnesium, and ether. Iso applied in a direction at right angles to the straight line indolinones, isomeric with arylamidoketones, are obtained joining the centres of the discs. The charge acquired in a —The hæmopoietic activity of the different organs in th given time by the insulated disc, when different strengths course of the regeneration of the blood : Paul Carnot and of magnetic field were applied, and when the electric field Mlle. CI. Deflandre.---The experimental infection of between the discs had different values, was measured.

trypanosomiasis by naturally infected Glossina palpalis Tables of results are given, and these are also plotted in L. Cazalbou. Two out of seven specimens of Glossina the form of curves, showing the variation of the current

palpalis, captured on the banks of the river Bani, a large between the discs with varying magnetic and electric fields.

tributary of the Niger, have infected dogs with trypano From the results obtained the author arrives at the follow

somiasis. A cat was similarly infected. The movement of ing conclusions :

the pole at the surface of the earth : Marcel Brillouin. (1) That under ordinary conditions, i.e. when not acted

A discussion of the curves published by M. Albrecht since upon by an electric or magnetic field, the polonium gives 1890. of a larger amount of negative than of positive rays.

(2) Under the influence of a gradually increasing electric field more and more of the slowly-moving negative rays are stopped, and the charge carried by the a rays becomes


PAGE more and more predominant.

Some Recent Works on Philosophy

533 (3) A potential difference of about 10 volts between the plates is sufficient to stop the last of the 8 rays.

Sea Fisheries Administration and Research

535 (4) The slowly-moving negative rays can also be pre

An Encyclopædia of Physics vented from striking the insulated plate by curling them Garden-Botany ...

537 up in a magnetic field. When they are stopped in this Our Book Shelf :latter way, however, the quantity of positive electricity

Meldrum : “Avogadro and Dalton. The Standing received by the insulated plate is only about one-fifth of

in Chemistry of their Hypotheses.”—A. S. that received when an electric field is used to stop the


Gruner: “Die radioaktiven Substanzen und die ô rays. The author explains this last fact as follows :

Theorie des Atomzerfalles.”—F. S. When the potential difference between the two plates is

Moulton : “ Introduction to Astronomy.”—W. E. R. 53% 10 volts or more (the polonium being positive), the positive

Letters to the Editor :current from the polonium to the other plate consists of two parts, viz. a stream of positive a particles in the direc- The Recent Radium Controversy.-Lord Kelvin, tion of the current, and a stream of negative particles in

O.M., F.R.S.

530 the opposite direction given off by the insulated plate. A

Stress in Magnetised Iron. -Dr. c. Chree, F.R S.

530 magnetic field curls up this latter stream of negative rays, The Rusting of Iron.-J. Newton Friend as well as the 5 rays given off by the polonium.

The Mixed Transformation of Lagrange's Equations. The author also points out that his results showing the

-A. B. Basset, F.R.S. magnetic and electric deflection of the 8 rays are not in

Suspended Germination of Seeds.-H. B. P. agreement with those obtained by Ewers with another Optical Illusions on Electric Fan.-T. Terada sample of polonium.

Aquatic-dwelling Weevils.-E. E. Lowe

Remarkable Rainbow Phenomena.-George C. Paris.

Simpson; Rev. C. S. Taylor Academy of Sciences, September 17.-M. Troost in the Some Scientific Centres.-IX. The Metallurgical chair.-The International Congress for the Study of the Department of the Sheffield University. (discia Polar Regions : G. Bigourdan. The congress was held trated.) at Brussels on September 7, and was attended by delegates Earth-Eaters in India. By N. W. T.

545 representing fifteen countries and eighiy learned societies.

Notes Seven standing committees were formed, each concerning Our Astronomical Column :itself with a special group of sciences. The formation of

Astronomical Occurrences in October an International Polar Commission was decided upon, and

The Total Solar Eclipse of January, 1907 bye-laws drawn up.--The deviations from the vertical in the region of the Sahel, Algeria : R. Bourgeois. In the

Observations of Phoebe in May and June, 1906

The Colours of Sun-spots triangulation of Algeria, the summit of the Voirol column was taken as the junction of the network of triangles.

Colours and Magnitudes of Double Stars The national observatory, founded some years later, is

Rotation Period of Jupiter's Equatorial Region about 5 kilometres in a direct line from this column. If Geology at the British Association. By J. L.

$49 the astronomical latitude of the observatory is compared | Zoology at the British Association. By Dr. J. H with the geodesic latitude of the same point, the calcula- Ashworth tion being made starting with the fundamental coordinates The Royal Photographic Society's Annual Exhibi of Voirol, a relatively considerable discrepancy is found, tion. By C. J..... indicating a strong deviation from the vertical at one or

Geodetic Operations in South Africa. By W. E. P. 554 other of these two points. In the present paper it is

University and Educational Intelligence .

554 shown that it is the Voirol station which is at fault, and hence all the data built on this as a starting point require Societies and Academies .



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