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Colorado Museum, Colorado Springs, U.S.A., which is in next :--the founding of a chemical Reichsanstalt. Dr connection with a large college recently established there. Treumann; the need of reform in the wine lans, Dr Before leaving Cape Town, Mr. Sclater completed the Kayser; on the radio-activity of the waters of health

Birds of his series of the " Fauna of South Africa " resorts, Dr. Aschoff ; on the analysis of certain coals, by the issue of the fourth volume. It is to be hoped that Prof. Dr. Heyer ; on the conditions imposed on industrial his successor will be induced to carry on this important chemists when appointed, Dr. Treumann; modern milk work to a conclusion.

hygiene, Dr. Lenze; demonstration of an apparatus for Mr. Michael John Nicoll, who recently returned photomicrography, Dr. Wilhelm Lenz; modern methods from accompanying the Earl of Crawford as naturalist

lighting, Dr. Thiele; on the preservation of serrery oi during his winter voyage in the Valhalla, R.Y.S., round

analytical methods, Dr. Vaubel i investigations of the Africa, has accepted the post of assistant-director of the

phosphorus and sulphur compounds used in the manuiar

ture of matches, Dr. Becker; the occurrence of manganes Zoological Gardens at Giza, near Cairo, and has left

in well water and the determination of the same, Dr England to take up the duties of his appointment.

Woy. The Royal Economic Society is about to inaugurate an

A TUBERCULOSIS museum, to which the public is to be annual economic congress to be held in London in the

admitted free, will, it is stated in the British Vedical January of each year. The first congress will take place Journal, be opened at Darmstadt on August 29. The on January 9 and 10, 1907, when it is hoped that many

museum, which is the first of the kind in Germany, is inprominent economists, including visitors from foreign

tended for the instruction of the people in the nature of countries, will be present. It may be mentioned that Viscount Goschen, who has been president of the society months the museum will be transferred to some other town,

the disease and the means of its prevention. After two from its inception in 1890, now resigns that position.

and so on through the whole of the Grand Duchy of Hesse. The new president is the Right Hon. R. B. Haldane, M.P.

According to Engineering, some interesting experiments A COMMITTEE for the furtherance of cancer research has

have recently been carried out on the military Berlin-Zossen 'been formed by the Swedish Medical Society under the

railway line the object of which was to ascertain the chairmanship of Prof. Berg.

value of a new invention to prevent trains from Icaving We record with much regret the death of Mr. James the metals on account of faulty rails, breakages of wheels Dredge, C.M.G. (joint editor with Mr. W. H. Maw of or axles, or other causes. In order to make the experiEngineering), which occurred on Wednesday, August 15, ments as realistic as possible, 2 kilometres of line wert at the age of sixty-six years. Mr. Dredge took great given up to the purpose, and on this distance intentional interest in the various international exhibitions held both derailments were effected, the experiments naturally being in this country and abroad. He was created a Companion of interest to both the civil and military authorities. Thr of the Order of St. Michael and St. George for his services German State Railways suffer, it is said, an annual psas Commissioner-General for Great Britain at the Brussels penditure of 250,000l. through damage done by derail. Exhibition of 1897.

The death is announced of Prof. S. Tomaselli, of the ALTHOUGH the hydrographic appropriation by Congress University of Catania; of Dr. Alexander Bogdanov, has been reduced, the investigation of underground water, professor of pathology at Odessa ; also of Prof. Léon

in the eastern United States is still being conducted by the Adrien Prunier, director of the Pharmacie centrale des

U.S. Geological Survey, and the work is to be extended Hôpitaux, and member of the Paris Académie de later in the season. Médecine.

An economic investigation of iron-ore deposits in L'rah, At the seventy-eighth annual meeting of the Associ-Colorado, and the Lake Superior region will, it is stated ation of German Men of Science and Physicians, which is in Science, be conducted next year by Mr. C. R. Van Hise, to take place at Stuttgart from September 16–22 next, the of the U.S. Geological Survey. The mapping of the iron following addresses will be delivered :-transplantation in ores of the Iron Springs Special quadrangle of southern surgery, by Prof. Garré, of Breslau ; embryonal transplant- Utah was completed on July 1. A special topographic map ation, by Dr. Speman; regeneration and transplantation on a scale of 1:45,000, with 50-feet contour intervals, has in the animal kingdom, by Prof. Korschelt, of Marburg. been made of an area of 225 square miles. The ore deIn the medical section a report by Profs. Starling, of posits themselves were mapped on a still larger scale of London, and Krehl, of Strassburg, will be presented on 250 feet to the inch. The maps and the report on the chemical correlations in the animal organism.

district will be published during the coming winter. In addition to the courses of lectures on “ Hygiene in The department of vertebrate palæontology of tht its bearing on School Life" and " Food and Meat Inspec- | American Museum of Natural History has, according to

to which attention was directed in our issue of Science, no fewer than three expeditions at work this August 9, the Royal Sanitary Institute has arranged for

Mr. B. Brown is continuing the search for diruthe following courses :—the forty-second course of lectures saurs in the Cretaceous beds of Montana, Mr. W. Granger for sanitary officers, commencing on September 10; the is searching for fossil mammals in the Eocene formation teath course of practical training for meat inspectors, of Wyoming, and Mr. A. Thomson is exploring the later beginning on September 21; and Sanitary Science as Tertiary formations of South Dakota. applied Buildings and Public Works,” from

According to the British Medical Journal, an ingeniou. September 28.

apparatus, invented by M. Chaulin, for the destruction of The following lectures are announced for delivery at the mosquitoes was recently presented to the Paris Acaderas meeting of the Verband selbständiger öffentlicher It is a simple kind of metallic cage formed line chain: Chemiker to be held in Dessau from September 23-25 almost touching, and held rigid by two metallic rings abort








and below. This is suspended from the ceiling, ing plans, botany, zoology, chemistry, and economics to apiernating electric current passes through the apparatus, form an Imperial Forest Research Institute at Dehra Dun.. and the insects, which are attracted by an electric light | The Indian Forester (June) contains a copy of the resolushowing within, are literally electrocuted.

tion and a short editorial note voicing the appreciation

of the Service, and pointing out the necessity for working SUBSTANCE that is spoken of as “a kin of celluloid"

out sylvicultural problems for and in India. The editor nies recently been patented in Italy by an English inventor. also contributes a second article, with illustrations, on the Celluloid, as is well known, is largely used as a substitute

types of forest rest-houses in India--the first article for tortoiseshell in the manufacture of combs and other appeared in the February issue--contrasting · the poor -mall articles, but the use has always been attended with

accommodation provided in Burma with the more sub. a certain amount of risk from its inflammable nature. It

stantial quarters found in the United Provinces. is claimed for the new invention that in the most aggravated circumstances it will only carbonise, and not flow Prof. A. H. R. Buller has taken up a useful subject like a stream of melting sealing wax, setting fire to any for research in making a study of the basidiomycetous niammable substance that may happen to come in its fungus, Polyporus squamosus, that grows as a wound paraway. The immunity from taking fire is secured by mixing site on maples, elms, and other trees. An account dealing glue, gum arabic, and colza oil with the original substance with the life-history of the fungus and its action on the when in a liquid state, and purifying it from sediment by wood of Acer is published as vol. i., No. 3, of the Journal various processes, until it becomes perfectly clear, when it of Economic Biology. As observers have noted for the can be worked up to resemble any kind of tortoiseshell at spores of other basidiomycetes, germination is not easily sery much lower price.

effected ; spores were germinated in artificial media, such Of the 728 persons who in 1905 underwent preventive asparagin, but the factors necessary to natural germination

as malt-wort extract and solutions containing peptone and Treatment for hydrophobia at the Pasteur Institute in

were not discovered. Prof. Buller has devoted a separate l'aris, four only died of the disease, and in one of these

paper, published in the Annals of Botany (January), to his. cases the disease manifested itself before the completion of

examination for ferments, in which his tests point to the ihtreatment. Excluding this case, the total mortality nous a percentage of 0.54. In the preceding year the

presence of seven ferments, including amylase and emulsin,

but the tests for maltase and invertase yielded negative umber of persons treated was slightly higher, being 755.

results. The persons treated at the Paris Institute are divided into thrup categories, as follows :-(a) Where the presence of COLOURED drawings made by Prof. L. Errera in connecrabies in the animal which inflicted the bite has been tion with his studies on glycogen and paraglycogen in the proved experimentally by the development of the disease fungi, to which reference was made in NATURE, June 7, in animals which were bitten by it or were inoculated p. 134, have been discovered, and have been issued as part with its medulla ; (b) where the presence of rabies in the of vol. i. of the Recueil de l'Institut botanique, Brussels. animal which inflicted the bite has been confirmed by The test consists in producing a distinct red or brown srterinary examination ; (c) where the animals in question colour with a solution of iodide in potassium iodide, that. were supposed to be suffering from rabies. One hundred disappears on heating strongly and reappears on cooling. and sixty-six of the persons treated are comprised in A very marked reaction was obtained with the zoospore of lass (a), 306 in class (b), and 255 in class (c).

Polyphagus Euglenae, with the young oidium of SphaeroA STRIKING proof of the value of the finger-print method

theca Castagnei, and with the young ascus of Geoglossum

hirsutum. of identifying criminals is to be found in the recently issued report of the Commissioner of the City Police. During the

According to the report for the past year, the Boston past year 1028 persons were arrested for offences under the

(U.S.A.) Natural History Society is making satisfactory Prevention of Crimes Act, such as being found in enclosed

progress in the matter of exhibiting a complete collection premises or in other circumstances suggestive of felonious of the fauna of New England. During the year specimens. intent of these individuals 562 were not recognised at

of moose and caribou have been installed, while the series the time of their apprehension as having previously been of birds has been increased by specimens representing, under arrest, but on their finger-prints being taken and

thirty-three species new to the collection. compared with the Scotland Yard registers it was ascertained that 265 of them were old offenders.

In an exceedingly interesting article published in the

August number of the American Naturalist Prof. R. S. RECOGNISING the danger to art which was entailed by

Lull discusses the various structụral modifications for flight the use of cheap aniline dyes, the Amir of Afghanistan occurring in vertebrates. Inclusive of extinct forms, volant some time ago forbade the entry into his territory of

evolution, in the author's opinion, has occurred in sevencarpets coloured with such dyes. The Kashmir Durbar

teen distinct instances, ten of which are, however, merely has now, according to the Pioneer Mail, taken a step which should assist materially in saving the various beautiful

adaptations for soaring leaps. Among these latter Mr.

Lull includes the so-called flying-frogs (Rhacophorus), the arts for which the vale of Kashmir is famous from deterior

volant powers of which have been ed, and th ation or destruction. The Durbar has decided to charge


lemurs (Propithecus) of Madagascar, the long leaps of a heavy duty of 45 per cent, on all aniline dyes at the frontier, and at a certain district within the frontier to

which are said to be aided by a rudimentary patagium. confiscate and at once destroy them.

In connection with flying-fishes, it may be noted that the

author considers Colonel Durnford to have definitely proved Wiile acknowledging the good results obtained in the the necessity for wing-vibrations. As regards pterodactyles, past by the Forest Department, the Government of India Mr. Lull is of opinion that while the long-tailed Rhampho-has decided to make better provision for scientific research rhynchus flapped its 'wings during flight, the gigantic in connection with Indian forests by the appointment of Pteranodon of the Cretaceous had a sailing light, with sis special officers for the branches of sylviculture, work- ! little or no wing-flapping, and may, indeed, have been


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unable to fly at all except on a windy day, when, by thickness of the ice-prisms. For rain-drops in clouds and facing the wind, it would be able to rise to a considerable fogs the diameters are found to be between 20 u and about altitude before its inertia was overcome.

100 H.

Dr. Pernter points out that these dimensions only

hold good when no precipitation is falling, and further that IN connection with the foregoing paragraph we may

it does not follow that still smaller ice-crystals, &c., may take the opportunity of referrin to the marked discrepancy

not be floating about in the clear atmosphere, their number in the matter of nomenclature which distinguishes the being too few to cause any visible appearance of on. papers of systematic specialists from those of biologists densation. with a wider range of studies. In Prof. Lull's paper, for instance, the flying-lemur is referred to by the time- In a memorandum (dated August 5) on the metrorological honoured title of Galæopithecus, whereas in a recent paper conditions in Egypt and the Sudan during July, Captain by Mr. G. S. Miller (Proc. U.S. Nat. Mus., No. 1481) we Lyons, director-general of the Survey Department, find it figuring as Cynocephalus, a name until recently estimates that the Nile flood will be near the average this used for the baboons. As the president of the Bavarian year, so far as information is at present available; the Ornithological Society remarked in his address for 1904, in critical period is said to be the first ten days of August, connection with the proposed transposition of the names as the volume of the flood depends on the level attained Tardus musicus and T. iliacus, all these changes of long- by the Blue Nile being maintained for a sufficient time established names, even when the alteration was justifiable, during this month. The rainfall recorded at the principal should be most rigorously guarded against, as the greatest stations around the Nile basin in July shows that the confusion would be the only result."

excess, which had been persistent since the beginning oi In addition to Prof. Lull's communication, the August the fall over the Sudan plains bas been somewhat above

the year, is now, however, replaced by a deficiency, while number of the American Naturalist contains an article by

the average at most stations from which observations have Messrs. Dexler and Freund on the external morphology of

been received. the dugong, which is illustrated with reproductions from photographs throwing new light on the form of the muzzle. The Psychological Bulletin (vol. iii., No. 4) contains an In the third article Mr. M. L. Hammatt describes the article by Prof. G. M. Stratton on the character of conmanner in which the anemone Metridium marginatum sciousness. The conclusion to which the writer comes is multiplies by fission. After either natural or artificial that consciousness is either the generical mark of all fission, “the fragment cut off curls together until its psychic processes or else a special one of these processes, extremities meet, making parts of mesenteries before nearly viz. that of knowing. If, therefore, we apply the term conparallel now radial in position, thus attaining to the sea- sciousness to the act of cognition, " it should not be underanemone structure with the least possible expenditure of stood that knowing is the supreme function in the world of energy.

objects, or that it really breaks loose from those connec

tions with feeling and will which modern psychology has IN vol. xxii., art. 2, of the Bulletin of the American

recognised." Consequently, it seems to him that it would Museum of Natural History, Prof. H. F. Osborn publishes be best to say knowledge " when we mean “ knowledge," a complete description and restoration of the skeleton of

and to let the term “consciousness " designate the common the gigantic carnivorous dinosaur Tyrannosaurus from the

and generic features of our psychic acts. Upper Cretaceous of North America. The creature stood about 16 feet, to the crown of the head, and there is a The Bulletin de l'Institut Général Psychologique possibility that it may have carried an armour. The most (50 Année, No. 6) contains two interesting articles, one a remarkable feature in its osteology is the presence of a full account of the marine laboratory at Wimereux, founded series of abdominal ribs comparable to those of the in 1874 by Prof. Giard, the other on the fifth international tuatera (Sphenodon), such structures having hitherto been psychological congress held at Rome last year. A short unknown either among dinosaurs or crocodiles. The author account is given in this last of the dispute between Flechsig states, however, that they have been found to exist in and Sciamanna regarding the localisation of functions in the the allied genus Allosaurus, and suggests that they may frontal and pre-frontal regions. The former maintained also be represented in the herbivorous sauropodous dino- that all the frontal region corresponded to the most elevated saurs, in which group they have been regarded as referable associations, the feelings of personality, of self-consciousto the shoulder-girdle.

ness, and of self-control, and that to the pre-frontal region

in particular belonged voluntary action. Sciamanna, alter As a contribution to the Hann jubilee volume of the

experiments on monkeys, came to the conclusion that in Meteorologische Zeitschrift, 1906, Dr. J. M. Pernter has

them, at any rate, the pre-frontal lobes could not be conselected the interesting subject of the determination of the

sidered as the seat of intelligence, morality and the like. size of cloud components from the phenomena of optical

but that these higher functions ought to be considered, as it meteorology, e.g. halos and coronæ round sun and moon,

rule, the result of the regular and harmonious working of and glories such as formed by the shadow of the observer,

the cerebral mass as a whole, and that any disturbantes like the Spectre of the Brocken, &c. Among the first to

consequent on lesion were to be attributed to the rupture undertake the measurements of the ice-crystals or minute

of this complete harmony. A committee appointed to rain-drops were Fraunhofer and Kämtz. Many of these

examine the monkeys before and after death confirmed measurements have been re-calculated, together with much

Sciamanna's account of their undisturbed mental condition, additional information obtained chiefly from observations

but, on the other hand, found that the removal of the frontal made on Ben Nevis, by using the revised formulæ of Airy

lobes had not been so complete as Sciamanna believed and Verdet. These measurements are given in detail in several tables; the general conclusions arrived at are that The Manchester Microscopical Society has just isura both in clouds and fogs, up to the altitude of the highest a revised list of the lectures arranged for delivery by clouds, the diameters of the ice-crystals are from about 5 u members of the extension section of the society during the to 20 , and that consequently 5 H is the lower limit of the coming winter. The object in view by the section is to


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9 66


bring scientific knowledge, in a popular form, before socie- of radiant energy. As in the volumes reviewed on a previous ties unable to pay large fees for professional lectures, and occasion, the two new parts are provided with notes on all fees paid for lectures are devoted to the working theoretical physics by MM. E. and F. Cosserat. expenses of the section. Applications for the list by the PROF. H. ERDMANN's “ Lehrbuch der anorganischen secretaries of natural history and kindred societies should Chemie," the fourth edition of which has just been pubbe made to the honorary secretary of the extension section lished by Messrs. F. Vieweg and Son, Brunswick, is a of the Manchester Microscopical Society at 22 Filey Road, comprehensive text-book containing nearly eight hundred Fallowfield, Manchester.

pages and three hundred figures. The work presents a Messrs. W'RATTEN AND WAInwright have sent us a batch

concise statement of the present position of inorganic

chemistry; it should be of service, not only to students of of their panchromatic plates, which have been recently pre- chemistry, but also to those concerned with the study pared in response to the demand for a plate having more

progress of other branches of pure and applied uniform sensitiveness to the various spectral colours. Very

science. searching tests on photographs of various spectral radiations show conclusively the unique qualities of the new emulsion. For instance, on a photograph of the spectrum of the iron

OUR ASTRONOMICAL COLUMN. are the green region, usually difficult to obtain with such COMET 1906d.--From an observation made at Lyons on Fxposures as give the blue of normal density, is shown of July 21, M. J. Guillaume recorded that Finlay's comet, on actually greater density than the blue ; at the same time,

that date, had a nebulous appearance with diffuse edges, the red end of the spectrum is very uniformly rendered up to

and that the central condensation was of the twelfth magni

tude, the magnitude of the whole object being 11.5. À 7000, and with slightly longer exposure somewhat beyond

The observation also showed that the position given by this. This particular batch of plates was of medium

M. Schulhof's ephemeris for that date needed but small rapidity, the sensitiveness measured to daylight being corrections; a further abstract from the ephemeris is given 94 H and D, 138 Watkins and F/94 Wynne. Development

below:took about 3 minutes for most of the exposures tried, and

Ephemeris (12h. M.T. Paris). the plates were clear and clean in working. An important

a (app.)
8 (app.)

log a factor in spectroscopic work is the fineness of the grain of Aug. 26 ... 5 6 19 +14 31 950197 10:25 the silver deposit, and in this respect the Wratten pan

28 ... 5 18 7

+15 18

9'51725 chromatic is excellent. There is no doubt that for spectrum

30 ... 5 29 17 +15 59

9:53258 9'08

Sept. I... investigation extending over the whole region from ultra

5 39 51
+16 37

9-54783 violet to extreme red these plates are the most satisfactory

The comet will pass about 1° south of 15 Orionis on ar present obtainable. If one might be permitted to ask

August 26 (Astronomische Nachrichten). for further convenience, it would be to maintain the A MEMORIAL TO THE LATE PROF. TACCHINI.–From No. 7, present colour sensitiveness ratios, and endeavour to in

vol. xxxv., of the Memorie della Società degli Spettroscopisti crease the general rapidity. Should it be found possible to subscription list has been opened for the purpose of found

Italiani, we are pleased to learn that an international do this and, at the same time, keep the grain within

ing some lasting souvenir in honour of that great Italian reasonable bounds, this type of emulsion would be of astronomer the late Prof. Tacchini. immense service for stellar spectrum photography, as for

A circular letter to this end has, evidently, already been this purpose a rapid plate is essential on account of the

addressed to the members of the society which he founded, fechleness of the light. A notable feature of the instruc

and a goodly sum thus realised, but not sufficient to

fulfil the object aimed at in a manner worthy of the tions sent out with the plates is the provision (for the first occasion. time, so far as we are aware) of a table showing the normal No doubt the fellow-workers and admirers of Pietro time of development for varying temperatures. It is well Tacchini, who did so much for the cause of astronomy, known that the temperature of the developing solution has a

will be glad to have this matter brought to their notice, considerable effect on the speed of appearance and subse

and to help forward the scheme. Subscriptions should be

addressed to Prof. L. Palazzo, Directeur du Bureau Central quent growth of the latent image, and as the new plates are

de Météorologie et Géodynamique, Rome. practically equally sensitive to all colours, requiring development in darkness, it is very advantageous to be

REPORT of the Paris OBSERVATORY FOR 1905.-Although

M. Lawy, in opening his report of the work done at the able to control by time the correct duration of the pro- Paris Observatory during the year 1905, mentions that cess. The figures given for this purpose are not arbitrary, observations were curtailed owing to the preparations for but have been obtained from exhaustive experimental trials, the total eclipse of the sun, the lamented death of M. Paul and can therefore be relied on without hesitation to give Henry, the necessary alterations to the principal meridian comparatively uniform results. The developer recommended

circle, and other causes, it appears from the report itself is a very weak combination of metol hydroquinone, but

that a great deal of work was prosecuted during the

year. excellent results have been obtained with other ordinary The publications included twenty-seven sheets of the developers, some much more concentrated, so that no dif- “ Cart du Ciel ” showing images of 39,697 stars, the ninth ficulty is likely to be found from this cause when the time part of the photographic atlas of the moon, the second best suited to the developer chosen is once determined.

volume of the “ Catalogue photographique du Ciel,” giving

the rectangular coordinates of some seventy thousand stars Two more parts of Prof. O. D. Chwolson's “ Traité de

between declination +22° and +24°, and the Annales for Physique," which M. A. Davaux is translating into French

1902. from the Russian and German editions, have been pub- difference of longitude Greenwich-Paris, and the reduction

Two important pieces of work, the determination of the listed in Paris by M. A. Hermann. The first parts of of the magnitudes and positions of the stars in the cluster vols. i. and ii. were reviewed at length in our issue for Messier 3, were completed. February 15 last (vol. Ixxiii., p. 362), and the present

The programme for the current year includes, among fascicles are the second parts of these volumes.

other things, the determination of the constant of aberraThe former

tion by M. Bigourdan, the measurement of stellar radial deals with the gaseous state of bodies, and the latter with

velocities by M. Hamy, and the photographical record of indices of refraction and the dispersion and transformations the ionisation of the atmosphere by M. Nordmann.


ITALIAN OBSERVATIONS OF THE TOTAL SOLAR ECLIPSE makes direct use of that property, as in the drawing of (1905).-An interesting illustrated report of the organisation, wires and tubes or the flanging of plates. He is concerned equipment, and results of the Italian observations of the too, with the hardening eflect that occurs in such processes total eclipse of August last is given by Prof. Ricco in when work is expended on permanently deforming a metal No. 7, vol. XXXV., of the Memorie della Società degli in the cold state, and also with the restoration to the Spettroscopisti Italiani.

normal condition of comparative softness which can be When first organised, the eclipse party included Prof. brought about by annealing. Nor can he afford to be in Tacchini, and, on his lamented death, the programme pro- different to the phenomena of fatigue " in metals, which posed had, therefore, to be somewhat modified.

manifest themselves when a piece is subjected to repeair-d Finally, it was decided that the expedition should make alternations or variations of stress-fatigue of strength and its observations at Alcalà de Chivert, the programme fatigue of elasticity, which, like physiological fatigue, including spectroscopic and direct observations of the admits under some conditions of rest-cure, inasmuch as il prominences, photography of the corona, photographic tends to disappear with the lapse of time. No apolog: observations of the spectrum of the eclipsed sun with a need be made in selecting for a Presidential Address in slit spectroscope and a prismatic camera, and observations Section G a subject that touches so many points of direct of the solar radiation, the ionisation of the atmosphere, practical interest to engineers. It is a subject which has and the polarisation of the coronal radiations.

for me the additional attraction of lying in the borderland Although the work was interfered with by clouds, some

between engineering and physics-a borderland in which interesting and valuable observations were made, and are

I have often strayed, and still love to stray, and I enter recorded in the article referred to above.

it to-day even at the risk of wandering into regions which, THE SPECTRA OF SUN-SPOTS {ND RED STARS. In a to engineers, may seem a little remote from home, region previous paper Profs. Hale and Adams considered the where the landscape has, perhaps, a suspicious likeness in question of the similarity of the spectra of sun-spots and

that of the country over which the learned men of of fourth-type stars, and arrived at the conclusion that the

Section A hold rule. coincidences met with in comparing the spectra suggested

To engineers, quite as much as to physicists and chemists, the existence of spots, similar to those on the sun, on such

we owe in recent years an immense extension of knowledge stars. Their evidence confirmed by Sir Norman regarding the structure of metals. This has come about Lockyer, who further suggested that the temperature con

mainly by the intelligent use of the microscope. Take any ditions of fourth-type stars, taking the absorbing atmo

piece of metal, in the state in which an engineer makes spheres as a whole, are about the same as those obtaining

use of it, polish and lightly etch ils surface, and examine in the restricted region of a spot nucleus in the sun's

it under the microscope, and you find that it is a congeries photosphere, both the stellar and the sun-spot atmospheres of a multitude of grains, every one of which may be proved having a lower temperature than that indicated by the

to be a crystal. It is true that the boundaries of each ordinary Fraunhoferic solar spectrum. In a paragraph grain have none of the characteristics of geometrica! added to the present paper, reprinted as a Contribution regularity which one is apt to look for in a crystal, but from the Solar Observatory, Mount Wilson (No. 8), Prof.

the grain is a true crystal for all that. Its boundarin Hale acknowledges the possibility of this suggestion afford

have been determined by the accident of its growth in ing the true explanation. Prof. Hale's conclusion was

relation to the simultaneous growth of neighbouring examined by Dr. W. M. Mitchell, who compared his grains--the grains have grown, crystal fashion, until the Princeton observations of spot spectra with the star spectra,

have met, and the surface of meeting, whatever shape in and

unable confirm the coincidences of the may happen to take, constitutes the boundary. But withia lines.

each grain there is the true crystalline characteristica In a paper now communicated to No. 5, vol. xxiii., of regular tactical formation of the little elements of which the Astrophysical Journal, Profs. Hale and Adams point the crystal is built up. It is as if little fairy children had out that in the spectra of fourth-type stars the spot lines built the metal by piling brickbats in a nursery. Each may be obliterated by bright lines, and that their apparent

child starts wherever it happens to be, placing its first absence may not, therefore, be accepted as final evidence

brickbat at random, and then piling the others side by until better photographs of the fourth-type spectra can be side with the first in geometrical regularity of orientation obtained. Such spectra will probably be obtained when

until the pile, or the branches it shoots out, meets the the 5-feet reflecting telescope is erected at Mount Wilson advancing pile of a neighbour ; and so the structure goes and a suitable spectrograph adapted to it. Comparing on, until the whole space is entirely filled by a solid mass the spot spectra with the spectrum of a Orionis, the same containing as many grains as there have been nuclei from observers show that the lines of the elements vanadium,

which the growth began. titanium, and manganese, which are strongly affected in

We now know that this process of crystal growth ostur spot spectra, are also especially strong in this third-type

not only in the solidification of a metal from the liquid star.

state, but in many cases during cooling through a “critical " temperature when the metal is already solid We know also that the process may in certain conditions

go on slowly at very moderate teniperatures. We know THE BRITISH ASSOCIATION.

also that the process of annealing is essentially the raising SECTION G.

of the metal to a temperature at which recrystallisatior may take place, though the metal remains solid while this

internal rearrangement of its particles goes on. Whether OPENING ADDRESS BY J. A. EWING, LL.D., F.R.S., crystallisation occurs in solidifying from the liquid or M.INST.C.E., PRESIDENT OF THE SECTION.

during the cooling of an already solid piece it results in the

formation of an aggregate of grains, each one of which is I INIEND to devote this Address to considering in certain true crystal. Their size may be large or small in aspects the inner structure of metals and the manner in general, quick cooling means that crystallisation starts which they yield under strain. It will not be disputed that from many nuclei, and the resulting grains are consequently this is a primary concern of the engineer, who in all his small; with very slow cooling you get a gross structuri problems of design is confronted by the limitations imposed made up of grains of a much larger size. on him by the strength and elasticity of the materials he For simplicity of statement I shall ask you in whol emplors. It is a leading aim with him to secure lightness follows to confine your attention to simple metals, omitrin and cheapness by giving to the parts such dimensions as any reference to alloys. Alloys present many complexitira are no larger than will secure safety, and hence it is of the into which we need not at present enter. With simple first importance to know in each particular case how metals every crystalline grain is made of the sume Suleme high a stress may be applied without risk of rupture or stance: the elementary brickbals are all exactly alike of permanent alteration in form.

Again, the engineer though there may be the widest variation from grain to recognises the merit, for structural purposes, of plasticity grain as regards ihe form of the grain, and also as regants as well as strength, and in many of his operations he the direction in which the elementary brickbars are piler.





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