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Velocity of wind=25-7 kilometres per hour=428 m. per that the second law of thermodynamics is applicable to minute.

the phenomena we have been discussing. The statement Thermal emissivity of leaf-surface in still air =0.0150 cal. of that law by Lord Kelvin limits its application to Thermal emissivity (e) in air of velocity of 428 m. per “ inanimate objects," and doubtless if the living elements minute=0.0150+0.00017 X 428=0.0577 calorie.

of the leaf-cells possess any power of dealing with the Hence mean temperature of leaf above that of surround- individual molecules of the surrounding medium so as to ings=r/2e=0.0502/ 2 X 0-0577=0°:43 C.

select and utilise the kinetic energy of those which are The disposal of the incident radiant energy deduced from moving faster than the “ mean square speed," it may well these data is given in the next table, the total incident happen that a leaf may be able to perform some kind of energy R being taken at 100.

internal work without there being any difference of mean

temperature between it and its surroundings. In this CASE A.Disposal of Incident Solar Energy by leaf - event the views I have put forward would doubtless require Helianthus annuus.

some slight revision, but I think we may well wait until Energy used for photosynthesis o 66

this restriction of the second fundamental principle of W transpiration 48.39

thermodynamics has received some experimental support. Total energy expended in internal work

'05 R- Ra Solar energy transmitted by leaf

3140 Energy lost by thermal emission

19:55

UNIVERSITY AND EDUCATIONAL

INTELLIGENCE.

MR. H. O. ARNOLD-FORSTER, M.P., will distribute the We will not consider another case in which the facilities

medals, prizes, and certificates at Woolwich Polytechnic for the performance of the internal work of vaporisation

on Saturday, April 1. of water were more than sufficient to use up the whole of the direct solar radiation absorbed by the leaf, i.e. Ra

Dr. E. 0. Lovett, professor of mathematics of Princewas less than W+w.

ton University, has been elected professor of astronomy in Such conditions are afforded by fully opened stomata,

succession to Prof. C. A. Young. high temperature, and a low degree of humidity of the THE Prince of Wales is to visit Cardiff toward the end of air. The leaves used were again those of the sunflower, June, when he will lay the foundation stone of the Welsh but in this case one-half of the solar radiation was inter- University College in Cathays Park. cepted by the revolving sectors.

Dr. Peter THOMPSON has been appointed professor of CASE B.-Helianthus annuus.

anatomy, and Prof. Arthur Dendy, of the South African

College, Cape Town, professor of zoology, at King's Solar radiation incident on leaf R

... =0'2746 calorie College, London. Coefficient of absorption, a=0.686, . solar

=0·1884 energy intercepted, Ra

The celebration of the jubilee of the Cheltenham Ladies' Water vaporised=0'000618 gram, .'. W, the

College and the opening by Sir Henry Roscoe of the new internal work of vaporisation=0'000618 *

science laboratories and lecture rooms will take place on ...=0'3668

Friday and Saturday, May 12 and 13. The Marquis of Rate of photosynthesis =0 000657 c.c. CO2,

Londonderry, President of the Board of Education, has hence w, absorption of energy due to assimi.

promised to be present. lation

...=0'0033

PRIVATE munificence has provided further sums for the Ra (W+w)

promotion of higher education in the United States. We 0'1884=0*3668 +0.0033 - 0'1817

learn from Science that by the death of Mrs. George L. Velocity of wind=12 kilometres per hour=200

Littlefield, Brown University becomes the recipient of the per

bulk of the Littlefield estate, estimated at 100,oool. The minute. Thermal emissiyity of leaf-surface in air of this velocity

will provides that the corporation shall apply the money

as it sees fit, except that 20,000l. shall be used for the = 0.015+ 200 X 0.00017=0.0490 calorie. Hence mean temperature of leaf below that of surround

establishment of the George L. Littlefield professorship

of American history. By the will of the late Mr. William ings="/2e=0.1817/0.0490=1°.84 C.

F. Milton, of New York, his estate will go to Harvard Case B.Disposal of Energy Received by Leaf from Solar

University on the death of Mrs. Milton. The daily papers Radiation and from Heat Conveyed from Surroundings.

state that it is worth between 200,00ol. and 400,000

Columbia University has received 20,000l. from Mr. Jacob R+1= 100.

H. Schiff to endow a chair of social work, and the new Energy used for photosynthesis 0972

professorship has been filled by the appointment of Dr. W transpiration 80:38

Edward T. Devine.

In the House of Commons on Monday Mr. Clancy asked Total energy expended in internal work 81:10

the First Lord of the Treasury whether there are any R- Ra Solar energy transmitted by lear

1890 requirements, statutory or otherwise, in the case of grants

in aid of university colleges in England, that four times

the amount is required from local subscriptions before any. During the time at my disposal I have only been able

thing is derived from the public funds. In reply, the to give a brief outline of the general principles under

Chancellor of the Exchequer said that there has been such lying an attempt to deal with the main functions of a a requirement in regard to the grant in past times. But foliage leaf from the point of view of its energetics, and

proposals in regard to the future allocation of the grant I must refer those of my hearers who are specially in

are now under the consideration of the Government. Ms. terested in the subject to the papers themselves for the

Clancy asked whether it was not proposed that there should further elaboration of the argument and for the facts on

be a grant of 100,000l. a year to the university colleges which it is based. I trust, however, that this short

mentioned in the report; and whether there was any ra account of the work may be sufficient to indicate that we

quirement, statutory or otherwise, in regard to this grant. have experimental means of studying quantitatively the

The Chancellor of the Exchequer answered: There is a reception of various grades of energy by a leaf, the pro

proposal by the committee that the distribution should be portion of this which is utilised for the two main kinds of governed by the amount of voluntary subscriptions obtained internal work, and also the thermal relations of a leaf to

by these colleges. The Government has not yet come to a its surroundings under given conditions.

decision on the subject. In conclusion, I wish to anticipate a possible objection At a meeting of the Association of Teachers in Technical which may be raised on theoretical grounds to some of Institutes on March 25. Mr. W. J. Lineham, chairman of the views I have expressed. I have assumed throughout the association, delivered an address on technical training us

W + w

100'00

arcs :

England. He insisted that in considering the future educa

Paris. tion of a boy who has completed his primary education Academy of Sciences, March 20.-M. H. Poincaré in the say, at thirteen—the subject must be regarded from the chair.-Thermochemical researches on brucine and strychpoint of view of his future livelihood. Mr. Lineham nine : MM. Berthelot and Gaudechon. A determination sketched what he called an ideal scheme of technical educa- of the heats of combustion and formation of the two alkation. After the child has followed a good primary loids, together with measurements of the heats of neutraleducation from the ages of six to thirteen, his education isation with various acids. The equilibrium between must be continued with some idea of his future occupation. strychnine and ammonium salts was also studied thermoIf he is to be educated for a commercial pursuit he should chemically.-On the variations of brightness and the total now attend a purely secondary school ; but if he is to eclipses of primary images formed on the retina by very enter a trade or technical profession he should attend what feeble luminous sources of constant value : A. Chauveau. is known as a day technical school until the age of A discussion of a recent paper by M. Lullin, in which the sixteen, having spent three years therein, the first part of latter describes an experiment with phosphorescent screens, which should be mainly literary, the middle scientific, and the visibility of which depends on the visual angle, and on the last technical. His apprenticeship should then begin. the duration of the observation.-On the valency of the But the apprentice must not now lose the lessons learnt in atom of hydrogen : M. de Forcrand. A discussion of the the technical day school. On the contrary, he must con- assumptions upon which the monovalency of hydrogen is tinue his studies to an even higher level by attendance based. The author brings forward the

cases

of at an evening technical school simultaneously with his Ag F, Ag,O, ICI,, and others, and suggests that the apprenticeship. As to the apprenticeship itself, its difficulty of explaining these can best be met by adopting character should entirely depend upon the trade or pro- the convention that the hydrogen atom is divalent.-On fession to be followed.

the photography of the solar corona at the summit of Mont Blanc : A. Hansky. Hitherto, attempts to photo

graph the solar corona at other times than during a total SOCIETIES AND ACADEMIES.

eclipse have not met with much success. By the use of a LONDON.

disc of blackened brass, the diameter of which is a little Anthropological Institute, March 14.—Sir T. H. Holdich,

larger than that of the image of the sun at the focus of K.C.M.G., K.C.I.E., in the chair.-Manners and customs

the telescope used, combined with coloured screens capable of the Melanesians : Rev. W. H. Edgell. The ethno

of absorbing the spectrum about up to 1=660 MH, photo

graphs of the solar corona have been obtained.-Remarks graphical objects and lantern slides shown included views of the different types of people, and illustrated the de

on the preceding note : J. Janssen. Reproductions of

two of the photographs mentioned in the preceding paper velopment of canoes and houses. One of the finest of the

are given.-The notion of distance in the functional slides illustrated a Melanesian waiting to shoot a fish. He was poised on one leg, and the lecturer stated that he

calculus : Maurice Fréchet.-On the calculation of closed had seen natives waiting motionless for hours by the side

M. Pigeaud.—The distribution and control of of the rivers waiting for an opportunity to shoot. Of

actions produced at a distance by electric waves : Edouard

Branly. The three effects chosen for control at a distance particular interest was the lecturer's statement that some of the natives have entirely lost the art of canoe making,

by means of electric waves are the starting of an electric although they still make paddles, which they use to propel plosion. Details are given of the apparatus by which this

motor, lighting incandescent lamps, and producing an exrafts made of bamboos.

has been done in the laboratory. The succession of the Entomological Society, March 15.- Mr. F. Merrifield, effects can be varied at will.-On the variation of the president, in the chair.-Exhibits.-Butterflies from Natal specific inductive power of glass with the frequency : André presented by Mr. G. A. K. Marshall to the Hope Depart- Broca and M. Turchini. Glass Leyden jars may be used ment at Oxford : Dr. F. A. Dixey. Dr. Dixey read a in the production of currents of high frequency, between note upon his experiments conducted with

view to the limits 10% and 3 x 10° per second, on condition that ascertaining whether the assumption of the wet or dry the capacity introduced into the formulæ is about one-half season form of various African butterflies could be con- that measured with charges of 0.1

or 0.7 of the trolled by exposure in the pupal state to artificial conditions capacity measured with the frequency of an ordinary of temperature and moisture.--Drawings of the genitalia rotating sector.-On the coefficient of specific magnetisaof noctuid moths, and also a number of slides showing the tion and magnetic susceptibility of salts : Georges Meslin. respective peculiarities of many members of the genus : The results of measurements for a considerable number F. W. Pierce. Among other things, attention of paramagnetic and diamagnetic salts are given.--On directed to the fact that in the case of the Tæniocampidæ photographic halation. Reply to a note of M. A. Guébthe genitalia were widely dissimilar, while the author's hard : P. Villard. The author regards the explanation of investigations had led him to conclude that Ashworthii, at his experiments given by M. A. Guebhard as inapplicable. present ranked as an Agrotis, should more properly be Particulars of an experiment are given for which an exincluded in the Noctua group.—A specimen of the Northplanation is at present wanting.--On the ionisation proAmerican longicorn, Neoclytus erythrocephalus, discovered duced between parallel plates by the radium emanatin.1 : in a sound ash tree in the neighbourhood of St. Helens, William Duane.-The diazoamines of diphenylamine, Lancashire : W. E. Sharp. Some palings of American derivatives of the homologues of aniline and naphthylash in the vicinity suggested the origin of the progenitors amines : Léo Vignon and A. Simonet.—The characterof the colony, but it was not known how long they had isation of lactones by means of hydrazine : M. Blaise and been erected. The beetles were taken in their galleries A. Luttringer. The lactone is heated on the water bath in the summer dead, which seemed to indicate a weaken- with a slight excess of hydrazine hydrate. The crystalline ing of the species under the conditions in which they mass which separates on cooling is re-crystallised from found themselves. Mr. Sharp also showed examples of boiling ethyl acetate, and its melting point, which is

Imara anthobia, Valle, new to the British list (with a usually well defined, serves to characterise the lactone. series of A. familiaris, Duf., and A. lucida for compari- The melting points of six of these compounds are given. son) from Leighton-Buzzard, where they occurred not in- On menthone derived from the hexahydrothymols : Léon frequently at the roots of grass in sandy places.-Muti- Brunel. In a preceding note the preparation of two lated Stenobothrus from the Picos de Europa, Spain : M. thymomenthols has been described; the present paper deeurr. These grasshoppers were taken at a height of scribes the thymomenthone obtained by the oxidation of about 1300 metres, on turfy ground exposed to north wind these products. On monobromoacetal : P. Freundler and from the Atlantic, and covered with tufts of a short, M. Ledru. By attention to some details the yield of dense, tough, and spiky shrub, together with heather. bromoacetal by Fischer's method has been raised from 50 Of the grasshoppers occurring on this spot, almost every per cent. to 115 per cent. of the acetal employed. Magspecimen had the wings and elytra more or less mutilated, nesium reacts violently on this bromine compound at 110°, sometimes actually torn to shreds, entirely altering their giving rise to vinyl ethyl ether.--Remarks on the diphenylappearance. A notable exception was St. bicolor, of which amine reaction with nitric acid : Isidore Bay. The blue no single specimen was found mutilated.

coloration is produced by a large number of oxidising

a

sec.,

was

a

agents, and is not characteristic of nitric acid.-On the CHEMICAL Society, at 8.-The Basic Properties of Oxygen at is antiseptic properties of certain kinds of smoke and on their Temperatures. Additive Compounds of the Halogens with Orgas

Substances containing Oxygen : D. McIntosh.-Note on the Intenso utilisation : A. Trillat. In previous papers the author has

of Metallic Cyanides and Organic Halides : N. V. Sidgwick -IS shown that formaldehyde is a constant constituent of

Chemical Dynamics of the Reactions between Sodium Thiosulptuazz sad chimney smoke. He now finds that a polymerised form- Organic Halogen Compounds. Part II. Halogen-substituted Acetat

A. Slator.-The Chemical Kinetics of Reactions with inverse Reacto aldehyde is always present in soot, in proportions varying

The Decomposition of Dimethylcarbamide : C. E. Fawsitt - The from 0.28 per cent. to 0.34 per cent.-The effects of phos

Tautomerism of Acetyl Thiocyanate : A. E. Dixon and J. Hawthorok phorus on the coagulation of the blood. The origin of A Method of Determining the Specific Gravity of Soluble Saits i fibrinogen : M. Doyon, A. Morel, and N. Kareff.—The Displacement in their own Mother Liquor, and its Application in the Case

of the Alkaline Halides : J. Y. Buchanan. -The Combination of Mercy duration of the process of stimulation for different muscles :

tans with Unsaturated Ketonic Compounds : S. Rubemann.-A M. and Madame L. Lapicque.-On the anatomical and Formation of Acetylcampbor: M. 0. Forster and Miss H. M. Jedda functional independence of the lobes of the liver : H. Preparation and Properties of 1:4 :5-Trimethylglyoxaline : H. A L Sérég é. The arguments from the anatomical and physio- Jowett. --Bromomethylheptylketone: H. A. D. Jowett -On the Eo

tence of a Carbide of Magnesium : J. T. Nance. The Action of Carba logical points of view are summarised and shown to be all

Monoxide on Ammonia : H. Jackson and D. N. Laurie.-Isomeric Sub in favour of the independence of the lobes.-An experi- of the Type NRR2H3. A Correction. Isomeric Forms of d-Bromo 2 mental study of the relations between the arterial pressure

d-Chloro-camphorsulphonic

Acids: F. S. Kipping:-Isomeris of and the pulmonary circulation in anesthesia by chloro

a-Bromoand a-Chloro-camphor : F. S. Kipping: -2-Phenylethylamine

F. S. Kipping and A. E. Hunter. form. The determining cause of chloroform accidents : J. INSTITUTION OF ELECTRICAL ENGINEERS, at 8.--Discussion of the Tissot.-On the measurement of disposable energy by a Report to Council on the International Electrical Congress at St. Loe self-registering integrating dynamometer : Charles Henry.

by W. Duddell, and of Papers on Systems of Electric Units Published a

Part clxx. (last issue) of the Journal. The apparatus consists essentially of a rubber ball filled . ROYAL INSTITUTION, at 5.-Synthetic Chemistry : Prof. R. Melod with mercury. The pressure of the hand on this raises a F.R.S. mass of iron up and down a graduated tube, this iron RÖNTGEN Society, at 8.15.-Exhibition Evening. being connected with the registering apparatus. The area

LINNEAN Society, at 8.-Intra-axillary Scales of Aquatic Mom

cotyledons: Prof. R. J. Harvey Gibson. - A further Communication registered measures the statical work done by the pressure the Study of Pelomyxa palustris : Mrs. Veley. of the fingers.—The cardiac area in cured consumptive SOCIETY OF Arts, at 4:30.-The Prospects of the Shan States : Ser: cases : H. Guilleminot.

George Scott.

FRIDAY, APRIL 7.

ROYAL INSTITUTION, at 9.-American Industry : Alfred Mosely. DIARY OF SOCIETIES.

INSTITUTION OF Civil ENGINEERS, at 8.- Cofferdams for Dock tz:

R. G. Clark. -Bath Corporation Waterworks Extension : J. R. For THURSDAY, MARCH 30.

SATURDAY APRIL 8.
ROYAL SOCIETY, at 4.30.-On the Observations on Stars made in some

British Stone Circles (Preliminary Note): Sir Norman Lockyer, ROYAL INSTITUTION, at 3.—Some Controverted Questions of Optica
K.C.B., F.R.S.-On the Distribution of Velocity in Viscous Lord Rayleigh.
Fluid over the Cross-section of a Pipe, and on the Action at the Critical The Essex FIELD CLUB, at 6.30. (At Essex Museum of Natural History,
Velocity : J. Morrow.---The Direct Synthesis of Ammonia : Dr. E. P. Stratford).--Twenty-fifth Annual Meeting.---Natural History Museum
Perman.-Tbe Determination of Vapour Pressure by Air Bubbling : Dr. F. W. Rudler.
E. P. Perman and J. H. Davies.- Note on Fluorescence and Absorption :
J. B. Burke.-The Determination of the Specific Heat of Superheated
Steam by Throttling and other Experiments : A. H. Peake.. - The Role
of Diffusion in the Catalysis of Hydrogen Peroxide by Colloidal Platinum;
G. Senter.-The Theory of Photographic Processes. Part II. On the

CONTENTS.

PAGE Chemical Dynamics of Development, including the Microscopy of the Image: S. E. Sheppard and C. E. K. Mees.

The Classification of the Sciences.

505 INSTITUTION OF ELECTRICAL ENGINEERS, at 8.

Elementary Mathematics .

507 FRIDAY, MARCH 31. Salt-beds and Oceans. By J. Y. B.

508 ROYAL INSTITUTION, at 9.-The Scientific Study of Dialects : Prof. J.

Evolution for Beginners. By F. A. D.

900 Wright.

Our Book Shelf :-
SATURDAY, APRIL 1.

Chassevant : “Précis de Chimie physiologique." — ROYAL INSTITUTION, at 3. --Some Controverted Questions of Optics :

W. D. H... Lord Rayleigh.

509 MONDAY, APRIL 3.

Söhns: “Unsere Pfanzen ”; Maxwell : “Children's SOCIETY OF CHEMICAL INDUSTRY, at 8.-On the Formation of Sulphuric

Wild Flowers"

STO Esters in the Nitration of Cellulose and their Influence on Stability : Gibson : “Superstitions about Animals"

510 C. Napier Hake and R. J. Lewis.-The Proof of Percussion Caps: H. W. Brownsdon.

Letters to the Editor :-
Society of Arts, at 8.-Telephony: H. L. Webb.
VICTORIA INSTITUTE, at 4.30.

A Great Oxford Discovery.-Prof. Karl Pearson,
F.R.S.

500 TUESDAY, APRIL 4.

Inversions of Temperature and Humidity in AntiROYAL INSTITUTION, at 5.— Tibet : Perceval Landon.

cyclones.--Dr. A. Lawrence Rotch

sto FARADAY SOCIETY, at 8.-Alloys of Copper and Antimony and Copper and The Planet Fortuna.-W. T.

Bismuth: A. H. Hiorns.--Refractory Materials for Furnace Linings :
E. Kilburn Scott.-Electrically Heated Carbon Tube Furnaces. Part 1.:

City Development. (Illustrated.)
R. S. Hutton and W. H. Patterson.

Nature's Ways. (Illustrated.) By R. L.

3ta INSTITUTION OF Civil ENGINEERS, at 8.-Continued Discussion : Coolgardie Water Supply: C. S. R. Palmer.

German Educational Exhibits at St. Louis

$13 Notes. (Illustrated.)

$13 WEDNESDAY, APRIL 5:

Our Astronomical Column :-
GEOLOGICAL SOCIETY, at 8.-On the Divisions and Correlations of the

Astronomical Occurrences in April
Upper Portion of the Coal-measures, with Special Reference to their
Development in the Midland Counties of England: R. Kidston, F.R.S.-

Discovery of a New Comet, 1905 a
On the Age and Relations of the Phosphatic Chalk of Taplow : L. Comet 1904 e (Borrelly)
Treacher and H. J. O. White.

Observations of the Recent Eclipse of the Moon
ENTOMOLOGICAL SOCIETY, at 8.

New Variable Stars in the Region about & Aquila
SOCIETY OF PUBLIC ANALYSTS, at 8.- The Determination of Higher
Alcohols in Spirits. I.: Dr. Philip Schidrowitz and F. Kaye.--The

Orbit of the Binary Star Ceti 82
Action of slightly Alkaline Waters on Iron : C. H. Cribb and F. W.F. Radial Velocities of Certain Stars
Arnaud.-Notes on Preservatives : E. G. Clayton.

Star Places in the Vulpecula Cluster.
SOCIETY OF Arts, at 8 ---Ancient Architecture of the Great Zimbabwe:
R. N. Hall.

The U.S. Coast and Geodetic Survey .
THURSDAY, April 6.

Protective Resemblance. (Illustrated.)
ROYAL SOCIETY, at 4.30.- Probabie Papers : On Reciprocal Innervation Report of the Carnegie Institution, 1904
of Antagonistic Muscles, Seventh Note : Prof. C. S. Sherrington, F.R.S.
- The Influence of Cobra-Venom on the Proteid Metabolism : Dr. James

The Reception and Utilisation of Energy by Scott.-- Further Experiments and Histological Investigations on In. Green Leaf. (With Dragram.) By Dr. Horace T. tumescences, with some Observations on Nuclear Division in Pathological Brown, F.R.S. . Tissues : Miss E. Dale. - On the Toxin-Antitoxin

Reaction, with Special University and Educational Intelligence the Nature of the Silver Reaction in Animal and Vegetable Tissues : Prof.

Societies and Academies A. B. Macallum.

Diary of Societies

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