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are free to follow the bent of this or that special inmates, is apt to be found in marshy situations where

In the long run, their united work is immensely these enemies cannot reach it. Most of the trees in profitable. Here is commercial rivalry, and more ; here Paraguay are subject to the attacks of the leaf-cutting

a better understanding of the right conditions of Atta, but, nevertheless, though unprotected by the presence applied science."

of Azteca, they continue to maintain their existence, even Lord Cromer, president of the society, took as a signal if belonging to introduced, and not native, species. instance of the necessity for experiments on animalso the Cecropia itself is not tenanted by ants until it is some recent discovery of a serum treatment in cases of epidemic years old. The presence of colonies of Azteca does not cerebro-spinal meningitis, that ghastly disease which goes prevent Cecropia from receiving much damage from the by the foolish name of 'spotted fever." It is an acute attacks of other insect enemies, and Fiebrig is of opinion septic inflammation of the membranes of the brain and that the constant loss suffered by the tree from the dethe spinal cord. By experiments on animals it was proved predations of Azteca itself involves a more serious drain to be due to special germs of the order of diplococci. upon its vitality than the occasional raids of the leafFlexner and Jobling, working at the Rockefeller Institute, cutters. Finally, the occupation of Cecropia by these ants discovered a way of preparing, from immunised horses, a not only fails to afford protection against enemies other serum containing a direct antidote, and this serum than the leaf-cutters, but even encourages the assaults of first used in the spring of 1907. Before that time there such formidable foes as woodpeckers and internally feedwas no special treatment of the disease, and the mortality ing lepidopterous larvæ. ranged from' 68.4 per cent. to 80.5 per cent.

The children With regard to the association between Acacia cavena -it was mostly children-suffered terribly, and died in a and Pseudomyrma fiebrigi, the author points out that this few days; and of those who survived many were left, tree, in common with other species of Acacia, is profrom the intensity of the inflammation, imbecile, paralysed, tected against the ground-haunting Atta by the fact that or blind. By the use of the serum the mortality has been it grows only in situations which are constantly liable to reduced to 36.7 per cent. In Belfast, of 275 cases treated inundation. The thorns in which the ants take up their before the use of the serum, 72.3 per cent. died, and of abode have frequently been already hollowed out and ninety-eight cases treated with the serum 29.6 per cent. furnished with apertures of access by lepidopterous larvæ ; died.

moreover, the spaces tenanted by the ants are not conThe Research Defence Society exists to keep the public fined to the thorns, but extend also to the stem. In neither informed of such facts as these, and we hope that it will situation do they occur naturally, but in both they are have a long record of such victories over disease.

cxcavated, as in Cecropia, whether by ants or caterpillars, at the expense of the living tissues of the tree.

On these grounds Ficbrig concludes that, at any rate

so far as the species observed by him are concerned, the IS THE ASSOCIATION OF ANTS WITH

benefits of the association between trees and ants are not TREES A TRUE SYMBIOSIS?

mutual, but are enjoyed by the ants alone. There is no THE fact has long been known that some species of

doubt that the reasons for his view adduced by Fiebrig ants occur in constant association with certain kinds

are of great weight. At the same time, it cannot be said of trees. Thus members of the dolichoderid genus Azteca

that these observations are sufficient of themselves to disare often found inhabiting the interior of the stems of

prove altogether the existence of ant-plant symbiosis,

F. A. D. Cecropia pe!tata, and among the Pseudomyrmini P. bicolor forms its nests within the spines of the “bull's-horn" acacia. The view has been held by many naturalists, amongst others by Fritz Müller and Bates, that in these

UNIVERSITY AND EDUCATIONAL cases the benefit is mutual, the tree affording both shelter

INTELLIGENCE. and sustenance to its occupants, and receiving in return protection from the attacks of the formidable leaf-cutting

OXFORD.--The following is the text of the speech ants of the genus Atta and of other enemies. Doubts on

delivered by Prof. Love in presenting Dr. G. E. Hale for this point have been expressed by several authorities,

the degree of D.Sc., honoris causa, at the Encænia on among them by Dr. David Sharp, in whose opinion " therć June 24 S is reason to suppose that a critical view of the subject

Inter Astronomos qui ea quæ in æthere solem circumwill not support the idea of the association being of supreme

fuso geruntur investigant nemini cedit Georgius Ellery importance to the trees.

Hale. Qui vir duodeviginti abhinc annos primus omnium A careful investigation of the relations subsisting fabricatus est instrumentum illud, ad lucis e solis puncto between the arboreal species of Azteca and Pseudomyrma quovis cmisse naturam cognoscendam aptissimum, quo and the trees which they inhabit has lately been conducted

hodie utuntur omnes fere solis observatores. Hoc subin Paraguay by Karl Fiebrig, who has published his

sidio fretus potuit Aammas illas excurrentes, quæ solis results, illustrated by numerous photographic reproduc- defectu plerumque cernuntur, sole pleno quasi in pictura tions, in the current volume of the Biologisches Central- cxprimere : mox plagas lucidissimo candore fulgentes, quas blatt.' His conclusions may be summarised as follows :

faculas vocant, eodem modo repræsentare. Idem nuper

vexantibus tenuissimas Azteca not only makes use of internodal cavities already docuit procellis hunc æthera existing in the stem of Cecropia peltata. but cxcavates

materiæ particulas quasi turbine quodam agitatas vim fresh spaces or enlarges existing ones at the expense of magnetica in miro modo gignere : quæ omnia nemo deliving tissues of the tree. Fritz Müller described certain

monstrare potuit nisi excogitandi peritissi:mus, in obserpits in the stem of Cecropia where the wall is much vando patientissimus, in causis cognoscendis sagacissimus. thinner. These spots, he says, are selected by the female Neque ei satis erat Naturæ arcana reserare, sed Obserant for the purpose of gaining access to the interior of vatoria duo in orbe terræ maxima fere et instructissima the stem. But, according to Fiebrig, the ants effect their condidit atque ornavit : idem Ephemeridem, in qua reentrance into new internodal spaces by perforating the centissima de siderum natura ubique reperta pervulgantur, partitions in the stem before they have gnawed through conscribendam curavit. Sodalicium denique maximum inthe thin bottoms of the pits; moreover, openings to the stituit quo omnes omnibus ex terris huius militiæ cælestis exterior are often made irrespective of the situation of the contubernales congregarentur. pits, and when the latter are perforated the boring is, in ST. ANDREWS.-Dr. William Nicoll, who has for some certain cases, effected from within, and not from without. years carried out important researches on the parasites Neither the internodal spaces nor the pits can therefore of birds, fishes, and other forms at the Gatty Marine reasonably be considered as myrmecophilous adaptations. Laboratory, has just been elected to the Ernest Hart Again, the alleged protection against leaf-cutting ants memorial scholarship. must often be superfluous, since the Cecropia, with its Dr. J. C. Irvine, lecturer on organic chemistry in the

liniversity, has been appointed by the University court to 1. "Cecropia peliata und ihr Verhältnis zu Azteca Alfari, zu Atta sexdens und anderen Insekten. Ein kritischer Reitrag zur Ameisenpflanzen-Hypo

the chair of chemistry in St. Andrews, vacant by the these." By Karl Fiebrig (San Bernardino, Paraguay).

iesignation of Prof. Purdie.

on

more

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The Viscountess Falmouth will present the prizes at the

consists of a president (Mr. S. S. Young), four EngliHorticultural College, Swanley, Kent, Thursday, professors in mechanical engineering, civil engineering. July 15. Sir John Cockburn will take the chair at mining, and physical faculties respectively, two Chine 4 p.m.

literati, and a clerical staff. A four years' course wa А DISTINGUISHED American physicist, Prof. E. F.

prescribed, and there are now more than 200 students ir Nichols, of Columbia University, has been elected presi- regular attendance from various parts of the country dent of Dartmouth College, a leading New England

Residential accommodation is provided for 160 students. institution with more than 1200 students. Dr. Nichols

together with houses for the staff, dining hall, and thre is a graduate of Cornell, and held chairs at Colgate and

educational buildings. All technical lectures are delivere. Dartmouth before being appointed to his present post at

in English. While the equipment is as yet far from: Columbia.

being complete, it is indisputable that the existence of

such an institution is a factor which cannot be disregarded The issue of The Record, the magazine of the South- when considering the future position of the Empire. Western Polytechnic Institute, Chelsea, London, for May, contains an account of this year's prize distribution, when of Toronto, had the degree of LL.D. of the University 61

Mr. David BOYLE, the curator of the Provincial Museum Dr. H. A. Miers, F.R.S., the principal of the University Toronto conferred on him on June 12, for his eminent of London, delivered an address. The report of the prin services in the cause of archæology and ethnology. Dr. cipal of the institute, an abstract of which is printed in the magazine, shows that there were 2573 students under Boyle has been incapacitated for some time, and as hi

was too ill to attend the regular Convocation, the authorhis supervision during 1907-8.

ties paid him the unique compliment of holding a specia: The King has consented to lay the foundation-stone of Convocation at his residence, and of conferring the degret the new buildings of the Imperial College of Science and while he was lying in bed. Dr. Boyle was presented by Technology, South Kensington, on July 8. The building Prof. Galbraith, and in the absence of the president, who is to accommodate the departments of mining and metal had sailed for England, the degree was conferred by the lurgy of the Royal School of Mines, geology of the Royal vice-president, Prof. Ramsay Wright. Dr. Boyle went 19 College of Science, and the extension of the engineering Canada in 1856, and in the face of great difficulties has department (City and Guilds College), and will be built up the fine archæological and ethnological collections situated on the land in Prince Consort Road lying to the in the Provincial Museum of Toronto. He is best known east of the Royal College of Music, and extending so far to students as the editor of, and chief contributor to, the as Exhibition Road.

annual archæological reports of the museum. They wert The fourth annual issue of the “Girls' School Year begun in 1898, and form a valuable record of Canadiar Book (Public Schools)” has now appeared. The book archæology and ethnology. The later reports have been becomes year by year complete, and certainly duly noticed in Nature. We congratulate Dr. Boyle on provides a useful directory for those interested in the this academic honour, which

life of selfeducation of girls. It is, however, still difficult to under- sacrificing and poorly remunerated toil for the subjects h: stand the editors' method of selection of schools for de

has so much at heart. tailed treatment. Among new features this year are The proceedings at the inauguration of Mr. R. C. articles on domestic science, teachers' registration, the Maclaurin as president of the Massachusetts Institute of teaching of music in public secondary schools, and a list Technology have been reported at considerable length in of lecturers suitable for schools. The volume is published the American Press. One of the chief speakers was Mr. by the Year Book Press, c/o Messrs. Swan Sonnenschein Bryce, who greeted the new president as a fellow-Briton, and Co., Ltd., and its price is 2s. 6d. net.

a fellow-Scotsman, and a fellow-member of Lincoln's Inn. A FULLY illustrated description of the college of engineer

Mr. Bryce said that Englishmen and Scotsmen would ing of the University of Illinois is contained in the issue naturally be sorry that Mr. Maclaurin was not serving of the University of Illinois Bulletin for March 8.

their country “in one of the new institutions which we Descriptions are provided of the work and equipment of

have lately founded to try to make up for lost time in the eight departments of the college, as well as those of

the promotion of scientific instruction. Still, "a scienthe engineering experiment station and the school of

tific inquirer and teacher helps the whole world by the railway engineering and administration. The college has

work which he does anywhere in it." In his own inbeen organised to give such training to young men as

augural address, President Maclaurin emphasised the will enable them to do efficient work in the branch of following articles in his creed as an educator :-(1) that engineering or architecture they may select, to meet the

the end of education is to fit men to deal with the affairs demand for highiy specialised instruction and research,

of life honestly, intelligently, and efficiently; (2) that in and to conduct investigations of value to the industrial

the higher education of a large and increasing section enterprises of Illinois and distribute the knowledge gained.

of the community science should play a very prominent,

if not a leading, part; (3) that science and culture must In the course of his recent presidential address to the

go hand in hand, science being studied and taught in Society of Chemical Industry, of which a short abstract

such a way as to make for that broad and liberal outlook appeared in NATURE of June 3, Prof. Meldola made the

on the world that is the mark of the really cultured man; following appreciative remarks on the modern methods of laboratory instruction in chemistry :-“ It is unnecessary

and (4) that " above all we must preserve in our students here to dwell at too great a length upon the general prac

the freshness and vigour of youth, and see to it with

all care that their natural powers of initiative are improved tical training, although I should like to add that if the level has been raised,' and if our teaching has become more

and not checked by our training." philosophical, we are mainly indebted to a former occupant

In recent years there has grown up in connection with of this chair, Prof. Emerson Reynolds, who is unquestion

local education authorities in all parts of the country ably the pioneer reformer in the laboratory teaching of

systems of scholarships providing for the education of chemistry: I am glad of this opportunity of acknowledg-boys and girls of varying ages and attending schools of ing the indebtedness of teachers to Prof. Reynolds, be

different grades, and also for young men and women cause, amidst the later clamour, his share in the develop

anxious to continue their education after school days are ment of chemical teaching has been overlooked." This

The report of the higher education subcommittee address is published in full in the current number of the

on the scholarship scheme of the London County Council, journal of the society.

recently adopted by the Council, provides an exhaustive

account of the educational facilities offered in London to EVIDENCE of the rapid development of the Chinese the sons and daughters of parents of limited incomes who Empire will be found in an article in Engineering for have sufficient ability, as tested by examinations, to profit June 18 dealing with the engineering and mining college by continued attendance at school and college. The report at Tang Shan, North China. This college was founded indicates that in London, as elsewhere, there has been a in 1906 for the education of Chinese students, and is in disposition to multiply unduly the number of scholarships connection with the Imperial Railways of North China, offered for competition, with the result that in certain both being under imperial administration. The staff districts there has had to be a marked lowering of standard

over.

a

far

mercurous

of efficiency so that the scholarships might be filled up. This danger, with others, has been under the considera

SOCIETIES AND ACADEMIES. tion of the committee, and steps have been taken in the

LONDON. case of certain classes of scholarship to reduce the number available, so that an efficient standard may be maintained.

Royal Society, May 27.-Sir Archibald Geikie, K.C.B., In framing the regulations which will

govern the award president, in the chair. -Notes concerning tidal oscilla

tions of scholarships and exhibitions during the next academic

upon rotating globe : Lord Rayleigh.—The year, the committee has endeavoured to arrange that, so

absolute value of the mechanical equivalent of heat in as possible, “no child or young person shall be

terms of the international electrical units : Prof. H. T. debarred' by poverty from obtaining the kind of education

Barnes. It is pointed out that the Clark cells used by which will prepare him for the career for which his

the author in his determinations of the mechanical equitalents and character best fit him, and that the pecuniary pared according to the old specifications. The absolute

valent of heat in terms of the electrical units were preemoluments attaching to the scholarships shall be sufficient to enable students to obtain the kind of education, whether

measurements of the Clark cell now being carried on industrial, scientific, or literary, which is best suited to

with such precision in the various standardising laboratheir needs and capacities, but not sufficient to induce

tories are expressed in terms of the new form of cell with

specially prepared them to undertake a particular course of study with the

sulphate. There is an object of securing the pecuniary advantages attaching to

important difference between the cells, which Wolff and the scholarship.”

Waters have shown amounts to 0.03 millivolts. The author

has compared a set of modern cells with cells set up As indicating the wide scope of the London County according to the old specifications, and finds the same Council scholarship scheme, which has recently been constant difference. Taking 1.4330 international volts at amended, it may be said that in 1905 the Council awarded

15° C. as representing the modern cells, then the cells (a) 2600 junior county scholarships to children between the made by the old specifications must be taken as 1.4333 ages of eleven and twelve, and that the annual cost of international volts at 15° C. The author's measurements awarding one of these scholarships annually was 851.; of the mechanical equivalent at different temperatures (6) 390 probationer scholarships, each costing 561., to were calculated on the basis of a value for the Clark cell children of thirteen to fourteen years of age ; (c) 100 inter- equal to 1.4342 international volts at 15° C. Re-calculating mediate county scholarships, each costing 1291., to boys on the new basis, the value of the mean calorie is found and girls of from fifteen to seventeen years of age; to be 4.1849 joules. This agrees with Reynolds and (d) fifty senior county scholarships, each costing some Moorby's directly determined mean, which, expressed 200l., to students more than eighteen years of age; and accurately for an interval of temperature between o° C. (e) various scholarships in science, art, and technology, at und 100° C., comes to 4.1836 joules. Rowland's mean an expenditure of more than 18,000l. To state the scholar- value between 5° C. and 35° C. is 4.185 joules, while the ships which are to be offered for competition this year author's value between the same limits of temperature is will indicate some of the changes which have been made 4:1826 joules. Thus, assuming the variation of the specific as the result of four years' experience. There are to be heat of water to be correctly determined, the value of the (a) 1800 junior county scholarships, costing each the same Clark cell, equal to 1.4330 international volts, brings the as in 1905, and 300 supplementary junior scholarships of clectrically determined mechanical equivalent into excellent lower value : (b) 300 intermediate county scholarships, but agreement with the same constant measured by mechanical the value of each, for sufficient reasons, has been reduced means.-An approximate determination of the boiling to 721. ; and (c) 150 senior county scholarships, each as points of metals : H. C. Greenwood. Although high in 1905, costing 200l. But, whereas the total expenditure temperatures can now be easily attained by means of in 1905 was 283,940l., the amount in 1909 has, notwith clectric heating, no general investigation of the boiling standing the greater wisdom of the conditions of award points of metals has yet been carried out. Moreover, in the scheme, been reduced to 263,08ol. The report of such values as are available have in most cases been the Education Committee gives very satisfactory evidence deduced indirectly, and are very discordant. In the preto show that the object the education authorities in London scnt investigation apparatus

devised for directly have in view is to secure a high quality in the results measuring the temperatures of ebullition under atmospheric they obtain, rather than to spread an incomplete and rudi- pressure of a considerable number of metals, allowing of mentary education far and wide.

use up to 2700° C. Heating was effected electrically, and A NUMBER of people interested in the teaching of house- the metal, when unaffected by carbon, was contained in craft and domestic science visited Battersea Polytechnic a thin-walled graphite crucible on the outside of which on June 29 to see the domestic economy training depart- the temperature was estimated by means of a Wanner

Since the department was opened in 1894 more optical pyrometer. The difference in temperature between than 400. students have obtained diplomas, and are

the internal and external surfaces of the crucible walls occupying responsible positions in leading institutions and was found to be negligible. Accuracy of the temperature schools; the present number of students above eighteen measurements was secured by checking the pyrometer years of age in the department is 130. Students of the against the “ black body melting points of specially

The department attend, in their first year, a course in “science purified strips of platinum, rhodium, and iridium. as applied to household work,” which includes physics, following values found :-aluminium, 1800° C.; chemistry, physiology, and hygiene. This course is taken antimony, 1440°C.; bismuth, 1420° C.; chromium, in addition to the purely practical work of the domestic 2200° C. ; copper, 2310° C.; iron, 2450° C.; magnesium, arts. During the second session the scientific basis of 1120° C.; manganese, 1900° C.; silver, 1955° C.; tin, knowledge thus obtained is applied in the practice kitchens, 2270° C. In dealing with the metals aluminium, laundries, and housewifery rooms and hygiene laboratories. chromium, iron, and manganese, which readily combine In the third year's course the same subjects are treated in with carbon, considerable difficulty was experienced in greater detail, special attention being directed to bacterio- avoiding contact with carbon at the high temperatures in logy and the examination of food-stuffs. The main objects question. This was finally accomplished by the use of of the science work are :-(a) to explain, so far as possible, aphite crucibles brasqued with previously fused, magthe chemical composition and properties of the materials

nesia. In the absence of this protective lining the boiling dealt with in household work ; (b) to explain the principal point was very greatly modified by carburisation. The chemical and physical changes taking place in the common temperatures indicated for aluminium and manganese were household operations involved in cookery, laundrywork, far below those hitherto supposed necessary for ebullition. &c.; (c) to give a training in the principles of scientific -Some results in the theory of elimination : A. L. Dixon. method. Special stress is laid on the fact that household The eliminant of two quantics 0(X), 4x), each of the nth degree, work generally is really an application of a number of facts may he expressed as a determinant the elements of which are and principles in chemistry, physics, hygiene, bacteriology, (as, re), where (a, r) is (o(a)u(r) – °(r)tla)]/(a - r), and aj, &c., and that, in order to understand the rationale of the an, ..

rm are two sets of n arbitrary quantities. For ordinary household processes, a knowledge of the general three quantics (x, y), 4(x, y), x(x, y), each of the form principles of the branches of knowledge just mentioned is Aror"y* (ran, szm), the eliminant is a determinant the elements necessary.

of which are Fla,, ba, ar, Be) where F(a, b, a, B)=(pla, b),

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Jugloxylon Hamaoanum, Populocaulis yezoensis, Fagoxyka are two sets of 2 min pairs of arbitrary quanuities. The eliminant hokkaidense, Sabiocaulis Sakurii, Cretovarium ja ponicum of two quantics 0(x), « *) may be expressed as a Pfaffian The phylogeny and distribution of these plants is considered

so far as possible. +[1, 2] [3, 4][5, 6] [211 – 1, 2n]

June 17.-Sir Archibald Geikie, K.C.B., president, i where (r, s}={p(a<,) +(a.) - plam)41 aér)/(ar + a.). The eliminant the chair. - The nature of the hydrogen Mocculi on the of three quantics p(x, y), 4(x, y), x(x, y) of the ordinary Prof. G. E. Hale. Photographs of the Holis standard form Aypł"y, (r + szu) is given by the Pfaffian

in the spectrum of the solar disc, made on Mount Wiko I+[1, 2][3, 4][5, 6] .

Ib[2n:- 1, 2n)

with high dispersion, were shown on the screen. where

line appears as follows :-(1) A broad dark line, differing

greatly in intensity and width in different regions of th [r, s}=(plarbo, ar + br), 4(a,dn, Qr+a), xlaqba, +6x))/

sun. Except in eruptive or rapidly changing phenoinena, (a, - b) (a, - br). the differences in width are not very marked. (2) With:

the boundaries of the dark line a narrow single or multip.-The liquidus curves of the ternary system aluminium- bright line is photographed in many parts of the un copper-tin : J. H. Andrew and C. A. Edwards. The

Sometimes the appearance resembles that of the calcium study of the constitution of alloys is of great theoretical

lines K, and K,-i.e. the bright line lying on its dari interest, and of some practical value ; in fact, it may be background is divided into two components by a centro said that the heat treatment of a given series of alloys dark line. In other regions the bright line is divided in, cannot be correctly , accomplished without accurate

a larger number of components, varying in width ar? knowledge of the structural changes which occur with separation. The images of dark hydrogen flocculi, a varying temperature and concentration. We are now in spectroheliograph plates taken with camera slit about possession of accurate data bearing on the constitution of equal in width to Ha, appear to be due, in the main, a large number of alloys containing only two elements, to local increase in the intensity of the dark line. 1 but very little work has been published on mixtures of some parts of the sun, particularly those where the line three or more metals. The object of the present research is distorted, variations in the width of the line may als

to throw some light on the properties of ternary play an important part. The increased intensity of the alloys, and, incidentally, the effect of impurities on binary dark line is probably the result of increased absorptior.. alloys. The metals from which the alloys were made had Slides were shown to illustrate the fact that prominences the following degree of purity :-

at the sun's brink are frequently recorded as dark fioccal Aluminium

when photographed in projection against the disc. The

99.57 Copper

possible effects of anomalous dispersion were discussed Tin

and photographs were exhibited of the same region of 99.98

the sun, taken simultaneously with light from the red Freezing-point determinations.—The freezing points of the and violet edges of Ha. The similarity of these photo alloys were determined directly after mixing by means of graphs apparently indicates that anomalous dispersion

10 per cent. iridium thermo-junction. The not the prime factor in producing the hydrogen flocculi. free ends of the wires were connected by a mirror galvano Certain minor differences suggest, however, that it may meter and balancing arrangement similar to that described perhaps play a secondary part in modifying their form.by Messrs. Carpenter and Keeling in their work on the The origin of certain lines in the spectrum of € Orionis iron-carbon alloys. In order to locate the position of the (Alnitam) : Sir Norman Lockyer, K.C.B., F.R.S., F. E. isothermal curves, more than 400 alloys and melting-point Baxandall, and C. P. Butler. The star

Orionis determinations were made. Conclusions. The character of (Alnitam) is of great importance as offering a possible the liquidus curves indicates that no well-defined ternary transition stage between the helium and bright-line stars, compound is deposited from any of the liquid alloys. The and the only outstanding lines of unknown origin were affinity of tin for either aluminium or copper is not

those

4097, 4379.8, and a conspicuous double at sufficient to overcome the affinity of the last two clements (4647:6. In the case of 4097, the clue to the identification for each other. As a consequence of the above, curves

1 46508 of the melting points of alloys containing a constant per- was obtained from a spark spectrum of chronium, showcentage of tin bear a striking resemblance to the liquidus ing local intensifications of certain lines at one of the curve of the aluminium-copper alloys. Tin is insoluble in poles. Two of these lines were found to be the previously by far the greater number of the alloys.-Studies on the known silicon (iv) lines, 4089, 4116, probably present as structure and affinities of Cretaceous plants : Dr. M. C. impurities in the fused chromium, while one of the it Stopes and Dr. K. Fujii. This paper is the first account maining two lines was found to coincide with the € Orionis to be published of the anatomy of Cretaceous plants line at 4097. These four lines are shown under various petrified in calcareous nodules. As an introduction to the conditions in the plate, indicating the steps taken in Aora, eighteen plants are described, all of which are new. tracing their origin to nitrogen. In the spectrum of The age of these plants is Upper Cretaceous, as is deter- nitrogen, under the special conditions which gave the mined from the ammonites which abound in the matrix above lines at 4097, 4103, another line was found at of the' nodules, and the locality of all the specimens 4379.8, which was greatly strengthened in comparison with described' is Hokkaido, northern Japan. The plants its intensity in the ordinary spark, and this line coincides include one fungus, three ferns, eight gymnosperms, and with the unknown linc in € Orionis. During the work six angiosperms. These numbers

represent, on the above lines, one of the photographs taken of an roughly, the proportions of the flora of the nodules as a alcohol spectrum showed abnormal intensifications whole, of which many more specimens are in the hands either side of the oxygen line 4649.2, suggesting the of the authors than are described in the present paper. presence of a new double. The wave-lengths of the conThe most interesting of the plants are :-a new type of ponents of this double were determincd as 4647.6, 4650-8, gymnosperm, Yezonia, of which the vegetative anatomy coinciding with the wave-lengths of the components of is different from that of any known genus; a gymno- the strong double in € Orionis. By a series of comparison spermic fructification, also new, which there is good reason photographs of spectra under varied conditions, the origin to believe belonged to Yezonia ; an angiosperm which is of the double was traced to carbon, and one of the strips included in the Sabiaccæ ; an angiosperm of the family of the plate (carbon spark in hydrogen) shows it quite Saururaceæ; and the first petrified flower, Cretovarium, isolated as it appears in the stellar spectrum. Further which has three carpels surrounded by the perianth. The evidence of the validity of the identification is afforded

of the described plants are :-Petrosphaeria by the peculiar nature of the components of the double. japonica, Fasciostelopteris Tansleii, Schizaeopteris meso- -Electric induction through solid insulators : Prof. H. A. zoica, Niponophyllum cordailiforme, Yezonia vulgaris, Wilson. This paper contains an account of a series of l'esoștrobus Oliverii, Araucarioxylon tankoensis, ' Cedroxy- experiments on the variation of the capacity of ebonite lon Matsumurii, C. Yendoii, Cunninghamiostrobus yubari. and other condensers, with the time of charging and with ensis, Cryptomeriopsis antiqua, Saururopsis niponensis, the potential difference. It is shown that the capacity

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a

concave

C after a time of charging t is given by the formula can be solved numerically in any particular case. In the C=C (1+ Blog (1 +pi)), where C, denotes the capacity paper' the velocity of propagation and the modulus of when t=0 and B and p are constants. In the case of decay are given for waves of length 2, 5, 10, 20 cm. at ebonite at 30° C. this formula represents the results the surface of mercury on which is superposed a layer obtained to within 1 part in 2000. The values of the of glycerine i mm. in depth. An estimate also obtained constants have been found for several substances for the damping when the wave-length is small compared different temperatures. The capacity is shown to be in- with the depth of the layer. Two other problems in the dependent of the potential difference within the limits of decay of surface waves are discussed.—The passage of error.

It is shown that after the temperature of an electricity through gaseous mixtures : E. M. Welliech. ebonite condenser has been changed, then a very slow (1) An experimental method (based on Langevin's method) change in the capacity goes on which continues for more has been devised in order to ascertain whether there are

100 hours at constant temperature.—The effect of two distinct mobilities for the positive or for the negative pressure on the band spectra of the fluorides of the metals ions produced by Röntgen rays in a mixture of two gases, of the alkaline earths: R. Rossi. It was shown by A. or of a vapour and a gas. (2) No evidence was found Dufour that the band spectra of the fuorides of the of the existence of the two distinct mobilities ; accordingly alkaline earths show a marked Zeeman effect, and it was it is necessary to conclude that the motion of the ion thought interesting to see whether these particular bands through the medium must involve a mechanism of a would also be displaced by pressure, for it is known that character such as to produce statistical average. the cyanogen bands, which, like most bands, do not show (3) Experiments were conducted with regard to the effect a Zeeman effect, are not displaced by pressure. The produced on the ionic mobilities in air by adding small large 213-feet

grating spectrograph of the quantities of vapours. The mobilities showed a marked physical laboratory of the Manchester University was used, decrease on the addition of alcohol and acetone, but were and the bands of the fluorides of calcium, barium, and not sensibly affected by the addition of the heavier vapours strontium were found to be shifted by pressure. 'The of methyl iodide and ethyl bromide. (4) Experiments were order of magnitude of the displacement is about the same performed with regard to the ionic mobilities in mixtures as for line spectra.—The components into which the bands of a gas and a vapour, the ions being formed from the are resolved are widened by pressure, and the linear latter constituent only. As a result of the experiments, it relation between pressure and displacement found by was shown that there must be, at all events initially, former observers on line spectra seems to hold also for a transference of the charge (both positive and negative) these bands. There does not seem to be any evident from the vapour to the gas molecule. (5) Experiments relation between the magnitudes of the Zeeman and were performed with regard to the stability of the vapour pressure-shift effect in the case of these bands.-The ions in the presence of hydrogen ; it was shown that the ionisation produced by an a particle : Dr. H. Geiger. vapour molecules can accompany thc charge to an appreciThe aim of the experiment was an accurate determina- able extent, even in the presence of a considerable quantity tion of the number of ions produced by an a particle when of hydrogen. (6) The mechanism by which the transcompletely absorbed in air. The most direct way to find | ference of charge from one molecule to another is effected the number of ions would be to measure the whole ionisa- has been discussed; there is reason to believe that the tion produced by the a particles from a known quantity of transference takes place by the medium of a detachable radium C. Since it is, however, practically impossible to unit of positive electricity: (7) From the experimental obtain the saturation current due to the a particles at results a theory of the mechanism underlying the passage atmospheric pressure, it was necessary to adopt an indirect of electricity through gases at ordinary temperatures and method. This method was briefly follows:- The pressures has been deduced.-A study of the use of photoionisation due to the whole number of a particles expelled graphic plates for the recording of position : Dr. C. E. K. from a known quantity of radium C was measured at a Moes.—The coefficients of capacity and the mutual low pressure, allowing only a small definite portion of attractions or repulsions of two electrified spherical conthe range of cach a particle to be effective. The ratio of ductors when close together : Dr. A. Russell. The comthe ionisation produced within this small portion of the putation of the electrostatic energy of two spherical conrange to the ionisation produced along the whole path | ductors when close together is an important problem in was then found from an accurate determination of the spark systems of wireless telegraphy. In this case the ionisation curve. It was found that the number of ions formulæ previously given for the capacity coefficients are produced in air by an a particle from radium C along its very laborious to evaluate. By extending a mathematical whole path is 2.37 X 10. Since the a particles from theorem due to Schlömilch, an approximate formula is different radio-active products differ only in their initial obtained for the sum of a certain infinite series. By velocity, it was possible by the aid of the ionisation curve using this theorem, it is shown that when the spheres of radium C to calculate the number of ions produced are close together the ordinary series formulæ for the by the other products.-A diffuse reflection of a particles : capacity coefficients can be written in forms which can Dr. H. Geiger and E. Marsden. It was observed that be readily computed to any required degree of accuracy. a diffuse reflection takes place when a particles are in- The author has re-computed and extended in this way cident on a plate. The reflected particles were counted by Kelvin's table for the capacity coefficients of two equal the scintillations produced on a zinc sulphide screen. The spheres when the least distance between them does not effect was found to vary with different metals as exceed half the radius of either. When the spheres are flectors, the amount of reflection being approximately pro- at microscopic distances apart, the formulæ become very portional to the atomic weight of the reflecting substance. simple. Kelvin's table also for the rates at which the Using different numbers of thin gold foils as reflectors, it capacity coefficients of two equal spheres alter with the was found that the reflection was a volume effect, and distance between them, when this distance does not exceed thus similar to the reflection of B particles. Taking a half the radius of either, has been re-computed and exmeasured quantity of radium C as source, and using a tended. When the spheres are very close together the plate of platinum as reflector, it was found that, of the laws of attraction and repulsion are simple. Let the incident a particles, about 1 in 8000 suffers reflection.- radius of each sphere be a, let x denote the least distance The decay of surface waves produced by a superposed between them, and suppose that the ratio V./Vof the layer of viscous Aluid : W. J. Harrison. An estimate is potentials of the two spheres is not nearly equal to unity, obtained of the effect of a thin layer of viscous liquid and that x'a is very small compared with unity. In this on the decay of waves at the surface of a slightly viscous case the mutual force between the spheres is attractive, liquid. The period equation for the motion is of the and is given by fourth degree, and has two real and two complex roots

a(V, - V., in the case of waves of less than a certain length, and

approximately

8.x four complex roots in the case of waves of greater length. The real roots correspond to dead-bent modes, the complex If the potentials of the spheres be equal, the repulsive roots to propagated modes. No general expression of any

force between them is, to a first approximation, given by use can be obtained for the damping, but the equation | Kelvin's formula for the repulsive force between two equal

as

re

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