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volts, have been produced; one company has even professed A new departure was introduced some years ago by the to manufacture a 200-volt 16-candle-power 25-watt lamp. Plaissetty soft mantle, and more recently the Cerofrim
Attention may also be directed to the cooperation between Company is stated to have made advances in the same the lamp-makers and the electrical supply companies direction. For such mantles it is claimed that their softcharacteristic of the United States, and to the work of the ness renders them convenient for package, and that they National Electric Lamp Association in that country. A naturally burn into the shape of the flame, and are thus large number of lamp-makers belong to this association, used under the most efficient conditions. The introducdetermine standard prices, and support a laboratory for tion of the inverted mantle has, of course, also been a the purpose of carrying out common tests on lamps for great advance, although only two years ago there were their mutual benefit. In addition, the cooperation between many who doubted its commercial possibilities. lamp-maker and supply company is naturally very beneficial At the same time, steady improvements in the design to both parties in pushing the sale of lamps in desired of inverted burners have proceeded. Many types on the directions.
market are specially designed to avoid discoloration of the
fitting through heat, to secure all the conditions most Electric Arc-lamps and Vapour-lamps.
favourable to complete combustion. Whittaker and Litle The most marked development in arc-lamps of late in the United States, and, more recently, Lebeis in years has been the introduction of fame carbons, that is, Germany, have described thermostatical methods of autocarbons such that the light comes from a bridge of in-matically regulating the access of air to the burner, which candescent vapour instead of the tips of the electrodes. By frequently requires adjustment, as the burner after lighting this means consumptions so low as 0-2 watt to 0.3 watt per gradually becomes heated. mean spherical candle-power are said to have been obtained. Perhaps the greatest advance has been in the direction Flame carbons, however, burn away very quickly, and in of high-pressure gas lighting, which serves to promote an order to extend their life lamps in which a succession of intimate mixture of gas and air, favouring complete comcarbons is automatically used have therefore been intro- bustion. To this end gas at high pressure may be used, duced. Another development, the enclosed regenerative or air at high pressure led into the burner, or a mixture lamp, involves methods enabling the access of air to the of gas and air at high pressure. In any case, however, carbons to be restricted, so that a high efficiency, and yet special external arrangements are needed with an exista fairly long life, is obtained. Mention must also be made ing low-pressure installation, Self-contained, highly efficient of the new Blondel flame carbons, yielding a very white lamps, which can be run off the ordinary low-pressure suplight, which have been stated to yield a polar curve of ply, have therefore been designed. For instance, the Lucas light-distribution specially well adapted for street lighting, lamp employs a small fan driven by an electric motor, and are burned vertically one above the other.
which receives current from a thermopile near the mantle. Another direction of progress has been the improvement in the Chipperfield lamp, a small hot-air engine placed of small candle-power enclosed arc-lamps, which formerly above the burner automatically pumps air under pressure served to bridge the gap between high candle-power flame into the burner. arcs and glow-lamps. By securing more complete ex- An important field in gas lighting is the use of autoclusion of the air from the globe, the Regina Arc Lampmatic ignition devices. These may consist of electric Company claims to manufacture a lamp consuming only sparking apparatus, of clock-work arranged to turn 0-8 watt per candle, and lasting for 250 hours without re- and off the gas by means of a bye-pass at specified hours, carboning. High candle-power metallic filament incan- or automatic devices of the same type manipulated by a descent lamps, which are manufactured up to 1000 candle-rise or fall in pressure. Clock-work systems are very power, now also serve to fill this gap.
trustworthy, but, of course, do not take account of peculiar The chief drawback of mercury-vapour lamps is, of atmospheric conditions, such as fog. Apparatus of the last course, the peculiar colour of their light, there being prac-type can be controlled from the station, and lamps can be tically no red rays. It has, therefore, been proposed to lighted up or extinguished as the engineer desires. mix certain salts wit the mercury,
use fluorescent Mention must also be made of the special Norwich materials, &c., in order to improve the spectrum, but few system for interior lighting and of the pneumatic methods ; such devices have come to a practical issue. A recent these, too, involve the use of the pilot flame. advance has, however, been achieved by Dr. Küch, of The subject of street lighting formed the object of study Germany, by the use of a tube composed of special quartz- of a deputation to the Continent recently appointed by glass, which can stand a very high temperature. By this the Corporation of London, and was subsequently investimeans a consumption of only 0.27 watt per mean spherical gated by the lecturer in a visit to Germany. A novelty candle-power is said to have been obtained ; an incidental of considerable interest, with which experiments advantage is that the luminescence in the tube seems to being made at Stuttgart, consists in slinging gas lamps be partially replaced by temperature radiation, and there- on wires spanning the street, just as is done in the case fore the light contains a distinct red element, the spectrum of electric arc-lamps in Cannon Street at present. Lastly. broadening out into a more or less continuous band instead in this section of the subject, the lecturer refers to the of consisting of isolated lines.
recognition of the importance of the heating power of gas. In addition, quartz-glass allows ultra-violet light to pass which is now regarded as more vital than its “illuminating through with special ease, and the lamp is therefore
according to the prescribed tests with flamebelieved to have special uses for the destruction of bacteria, burners, for modern methods of lighting, and discusses the photographic purposes, &c. For ordinary illuminating pur- suggestion of a calorific standard in the future. poses a special absorbing glass envelope restricting these
Gas, Oil, Acetylene, and other Self-contained Methods of rays is used. The Moore tube utilises gases in a rarefied
Lighting. condition and subjected to a high-tension alternating discharge. The essential feature of this arrangement is the
The simple method of lighting by petroleum lamps, the use of a valve which automatically keeps the condition of
author points out, should not be neglected. It is used, the gas within the tube constant.
for instance, in the Church of St. Sophia of Constanti
nople, where it is preserved on account of its decorative Gas Lighting.
value and because of religious tradition. In addition,
petroleum lamps are still used in the country, and give Great advances have been made in the efficiency of gas good results when properly handled ; in this connection the burners since the early flat-fame burners yielding only researches of Mr.' Guiselin, who has demonstrated the about 3 candle-power per cubic foot. The most recent
advisability of keeping the reservoir in oil lamps well figure is furnished by the Keith high-pressure light, for filled, are of interest. For instance, the illuminating power which 60 to 70 candles per cubic foot have been found by
was found to be improved by 20 per cent. when 700 cubic some observers.
centimetres instead of 500 were retained in the reservoir. Improvements have been made in the incandescent Recently many methods of incandescent oil lighting, that mantle both in the direction of the colour of the light is, the use of vaporised fuel with an incandescent mantle, and through durability. Even
SO, manufacturers in
have been devised. The Kitson system and the Empire England have stated that, as a rule, mantles require light are stated to be very efficient for lighthouse work renewing every 200 hours.
and for the illumination of large outdoor areas in remote
localities. Other types of lamps are the Blanchard, the and therefore we ought not to utilise artificial methods of Petrolite, &c., which are described in detail.
lighting differing too widely from diffused daylight. The A special account is also given of petrol air-gas light- importance of providing for proper access of daylight in ing, three typical systems, the Machine Gas Syndicate the design of buildings, particularly schools, is insisted (Cox's system), the Aërogen, and the National Air Gas, upon. In this connection, the choice of wall-papers and being exhibited. This system of lighting has attracted the scheme of decoration are of considerable importance. great attention recently for the lighting of private houses It is pointed out, too, that the intrinsic brilliancy of in districts where gas or electricity are not available. A illumination has gradually increased of recent years. The mixture of a small percentage of petrol vapour with air is effect of gazing directly upon such bright sources is very generated outside the building, and passed through pipes fatiguing and distressing to the eyes, and the author to the burner in the usual way.
suggests that the time is now ripe for Governmental reThe method of lighting by alcohol lamps is worth con- commendations on this point. sideration in agricultural districts where petroleum may In order to reduce the intrinsic brilliancy of light not be available, but alcohol is readily manufactured. sources, suitable shades may be employed, and special There are also a number of liquid-gas systems in which reference is made to the Holophane diffusing globes and gas is stored under pressure in liquid form, and has been reflectors, which enable the light to be distributed and coneffectively used for railway-carriage lighting, &c.
centrated in any desired direction.
Some particulars are given of recent progress in photoAcetylene Lighting.
metry. The line of development of special consequence Mr. Gaster deals briefly, with the historical development has been the introduction of so-called illumination photoof acetylene lighting, and describes the modern form of meters, which measure, not the actual intensity of the generator and several types of portable acetylene lamps ; source, but the actual illumination on the pavements or at these are frequently used in mines, for motor-cars, &c. the desk at which we read. Sir William Preece so long Acetylene, like petrol-air gas, finds its main application | ago as 1883 emphasised the value of such measurements.
Another interesting development is the Globe photometer, example of which is shown in the accompanying illustration.
Perhaps an exceptionally important development during the last year has been the establishment of the international unit of light between England, France, and the United States, and the recognition of a simple relation connecting this unit with the value in use in Germany. The success of cooperation in this direction in this country is felt to be largely due to the fact that representatives of the gas industry and the gas referees were invited to act with those connected with electricity on the commission studying this subject.
Turning next to some practical eramples of illumination, the author insists upon
the importance of adequate school · lighting, quoting many authorities to show that the evesight of school children deteriorates during school life: he suggests that tests of the children's condition should be accompanied by the preservation of data relating the methods of illumination emploved in such schools. as this is believed to have a very vital
influence on the health of the child. The Ulbricht globe photometer, by the aid of which the mean spherical candle-power of a source ca i
In the same way the lighting of be deiermined by a single measurement.
factories, hospitals, libraries, &c..
should receive very careful study, fer where gas and electricity are not available. A recent good illumination is as much a necessity as the provision of development of considerable interest is the method of disc adequate sanitation and good ventilation ; it is hoped that solving acetylene in acetone, which, at a pressure of ten in the future, conditions of illumination, like the matters atmospheres, absorbs about 240 times its own volume of referred to above, will become the subject of Government acetylene, but liberates it when the pressure is released. inspection and recommendation. In addition, it is pointed Tubes of dissolved acetylene have been widely used for out that even from the point of view of expediency portable lighting, on motor-cars, railway trains, and even employers would do well to pay attention to this matter, in emergencies for interior lighting. Perhaps one of their a relatively small expense involved in securing good most successful applications, however, is for the lighting lighting is more than counterbalanced by the improvement of buoys and beacons in remote localities.
in the quality and output of work. In hospitals it is There are several types of ingenious valves which are i obvious that the lighting should be exceptionally perfect, very effective in saving the consumption of acetylene in since people in an invalid condition are specially liable to the above circumstances. For instance, the Dalen solar feel the effect of bad methods of lighting. valve automatically cuts off the main supply of acetylene Libraries, again, are frequented by people engaged in in daylight, leaving only the bye-pass burning, and re- strenuous work and taxing their eyes severely; it is there kindles it at night.
fore suggested that in this case also no pains should be
spared to make the methods of lighting convenient to the General Problems in Illumination.
workers, and that when great expense is incurred in In the last of these four lectures Mr. Gaster discusses collecting valuable books and housing them in handsome the question of illumination in general terms. He again buildings, the provision for the necessary illumination directs attention to the increasing brilliancy of modern by the aid of which the books alone can be read should illumination, and points out that the eve
must have not be grudged. developed mainly in compliance with daylight conditions, A subject on which cooperation between different authori
ties is badly needed is street lighting. It is pointed ments:
In addition to the continuous use of the transit out that there is room for the establishment of some instrument for the deterinination of time, observations of central testing department where thoroughly trustworthy selected stars and of comets visible from the observatory and impartial tests could be carried out and used for the formed the chief astronomical work of the year. A Milne common benefit of those interested. In particular, it is seismograph for the registration of tremors in the earth suggested that it cannot be decided by the mere personal is kept steadily at work ; during the Messina earthquake impression of a non-technical body of observers whether (December 28) the duration of disturbance was ih. 41m., the lighting of the street is good or bad. This must be and the amplitude (half the complete range of maximum determined by the aid of precise scientific tests, carried out motion) was 15 inm. The meteorological results are very by impartial experts, who have made a thorough study complete, e.g. the wind observations show the maximum of the subject, and can provide records by which experi- velocity for each day recorded by Dines's apparatus, the ences can be checked and subsequently repeated.
extreme pressure on the square foot by Osler's anemoOther instances of problems in illumination in which meter, the horizontal motion by Robinson's anemometer, there is great field for scientific treatment are shop-window and the number of hours that the wind blew from different lighting, stage lighting, and light-house illumination ; in points of the compass. The mean temperature of the year the two former fields, in particular, there is ample scope (49.2°) was practically normal, and the rainfall (28.9 inches) for the ingenuity of those who are up-to-date in their slightly above the average. knowledge of the different illuminants, and possess, in The annual report of the United States Weather Bureau addition, the requisite taste.
for the fiscal year ended June 30, 1908, shows that the In the next section of this lecture Mr. Gaster deals with research work at Mount Weather Observatory has been the scientific basis of light production, pointing out how carried on without material curtailment, notwithstanding the nature of the radiation from an illuminant depends the destruction by fire of the administration building in in general upon its temperature, and indicating some of October, 1907. Investigation of the upper air by means the possible lines of future development. The figures of of kites and captive balloons is made daily (except Sundays), authorities in this matter differ very greatly, but it is and the data are telegraphed to Washington for the use of generally considered that the percentage of energy radiated the forecast division. The work on solar physics includes in the form of light is very small indeed. The problem the measureinent of solar radiation and the degree of of light production is complicated by the fact that some absorption by the atmosphere. Considerable discrepancies invisible kinds of radiation seem
a prejudicial exist in the values of the solar constant, even computed effect on the eye. The author describes some experiments from. observations on the same day at Mount Weather showing the nature of the ultra-violet rays, which some and at Washington ; in most cases these are traceable to authorities consider to be injurious.
the unsteadiness of the atmosphere. Great activity exists In conclusion, Mr. Gaster points out that the problem in the divisions dealing with land and ocean meteorology ; of illumination is a complex subject which deserves special the number of climatological stations now exceeds 3700, consideration by itself. There is a need for men who are and more than 1600 vessels cooperated with the Bureau not connected with any particular illuminant and who are during the year. All data referring to the Indian Ocean able to take a wide view of the different aspects of the are lent to the Indian Meteorological Department, where matter, so as to deal with modern problems of lighting. they are copied and returned. In the forecast division In order to focus interest in this subject and to bring into isobaric charts are prepared from daily telegraphic reports contact the engineers, architects, oculists, and others from selected stations throughout the northern hemisphere, interested in illumination, a society has been formed this and forecasts for about a week in advance were published year which will, it is hoped, gradually lead to the solution during the last three months of the year. The library of the important questions on which further exact data are now consists of about 28,000 books and pamphlets. In felt to
be desirable; this is termed the Illuminating addition, meteorological articles contained in periodicals Engineering Society. The first president of the society is and transactions are catalogued under both author and Prof. S. P. Thompson, and the opening session will com- subject ; this bibliography is said to be more frequently mence in November.
consulted than the catalogue of books.
The Survey Department of Egypt has published its
meteoroiogical report for 1907, containing hourly readings AVNC'IL METEOROLOGICAL REPORTS. at Helwan and climatological tables at thirty-five stations THE Deutsche Seewarte has issued part xvii. of its over- of the second and third order ; the monthly tables give tri
sea meteorological observations for 1907, containing daily readings in the form adopted by the International very carefully prepared summaries, and in some cases in- Meteorological Committee, and also include the daily dividual readings, at some thirty stations. The principal amount of evaporation, as that element is of considerable localities include Labrador, Morocco, Shantung, German importance in Egypt and the Sudan. Additional tables East Africa, and some islands in the Pacific Ocean ; there include hourly observations by Dines's pressure anemometer are also some isolated stations, including one recently at Alexandria, rainfall and wind direction for a number of established at Babylon. Scientific investigators will be stations, and river-gauge observations. In compliance grateful to the Seewarte for references which are given
with a desire expressed by the International Meteoroin all cases to the periodicals in which previous observa- logical Committee in 1907, tables of normal values are tions and results have been published.
also given. Rainfall
was in excess in Egypt and in The annual report of the Philippine Weather Bureau for North Sudan, but in considerable defect throughout the 1907, part i., contains hourly readings at the Manila rest of the Sudan, and, as we have previously stated, the Observatory, together with means deduced therefrom. The Nile flood was worse than any recorded during the past tables also show the extreme values recorded, and the departures of the monthly and yearly means from the The meteorological year-book of the Bremen Observatory average. The mean temperature of the year, 79:50, was for 1908 has been received. From small beginnings this practically norinal; the absolute extremes were 98.1° in institution, under the superintendence of the late Dr. P. April and 59.0° in January. The rainfall, 72.5 inches, Bergholz, has attained a position of considerable importwas 3:3 inches below the average ; of this amount 64 inches
the observations, which include hourly readings fell from June to October inclusive (the period of the south- and means, with monthly and yearly summaries, have been west monsoon). An appendix shows the greatest daily reduced by Prof. Grosse in the same thorough manner as and hourly rainfall registered at the observatory in past heretofore, with the addition of hourly tabulations of sunVears; the greatest daily falls were 13.3 inches and 12:1 shine records and monthly means of earth temperatures. inches, on September 24 and 25, 1867.
The valuable materials, which now extend over many The report of the Liverpool Observatory for the vear years, await a general scientific discussion; this de1908 has been received from Mr. W. E. Plummer. This sideratum is urgently pointed out by Dr. Grosse, but under useful establishment is maintained by the Mersey Docks present arrangements, while the director has to divide his and Harbour Board in the interest of shipping, and is energies between the observatory and other official duties, well provided with meteorological and astronomical instru- this important work has to be postponed.
WORK OF THE PHYSIKALISCH.
sufficiently dense kathodic rays. For the blue fluorescence TECHNISCHE REICHSANSTALT IN 1908.
it was shown that they are connected with the emission of
negative electrons. A fixed point for the presence of the FROM the annual report of the above institution for positive electrons could not be ascertained. last year, recently published, we find that the same
The experiments commenced in 1907 on the electrolytie stcady progress is made in research work of a varied properties of silver and copper were concluded, and show nature; the following notes give some particulars of a
that silver in the aqueous solutions of HCI, HBr, and Hi, few of the more interesting investigations completed or in
and copper in the aqueous solutions of HF indicate an progress in 1908.
electrolytic valvular action which does not appear, as in The saturation pressure of water vapour between 50° the other metals, to be caused by a gas stratum, but by and 200° was determined as a continuation of the experi- a solid stratum. ments in the previous year, the resultant pressures being For the determination of the absolute values of standards tabulated in the report. The limit of accuracy over the of self-induction, which are made by comparing, with whole range depended on the measurement of tempera- capacities measured absolutely, a standard air condenser ture, and the greater part of the work was devoted to such
was constructed. The new air condenser consists of 107 measurements. In the neighbourhood of 100° the tempera, magnalium discs of 20 cm. diameter, 1 mm. thickness, ture scale could be considered as trustworthy to o.or°, and and i mm. apart. It has a capacity of about 0.03 mfd. at 200° to 0.02°. The platinum thermometers used were Amber is used for insulating, the insulation resistance being compared at 150° and 200° with the nitrogen thermometer, of the order 1015 ohms. after the constants of the latter had been determined, the The work done in the magnetic laboratory includes a comparison being made in an electrically heated oil-bath.
comparison of the methods of testing magnetic materials The experiments on the heat of evaporation of water, and experiments on initial permeability. An exhaustive which were previously made between 30° C. and 100° C.,
series of measurements of self-induction was carried out have been continued for temperatures above 100°. Up to with high-frequency alternating currents, and papers bear. the present it had only been possible to obtain the values ing on this subject have been published. A rotating interfor the evaporation-heat from Regnault's observations of rupter for absolute capacity measurements by Maxwell's the total heat by calculating the heat of the water. It method is described. therefore appeared desirable to make direct measurements A number of tests were made on various forms of flicker of the evaporation-heat. The experiments were carried out photometer which could be used on a straight photometer between 100° C. and 180° C. The results show that in bench, with the view of determining whether the use of the first approximation it is admissible to extrapolate the flicker photometer is to be advocated for tests. It was beyond 100° the formula
found, however, that the flicker photometer offered to the L=94.2 10(365 – t)0•34124 Cal. 15,
skilled operator no advantage over the usual method of
measurement as regards rapidity and certainty of adjustwhich has been drawn up for the evaporation-heat L between 30° C. and 100° C. as limits for t.
Nearly seventy official and private papers of a scientific The work connected with the silver voltameter was nature by members of the staff were published during 1908, brought to a conclusion, and a paper published dealing particulars of these being given in an appendix to the with the subject. The object of the measurements was report. (1) to compare with the aid of the voltameter and a resistance the E.M.F. of the Weston normal cell, which was last determined by means of the silver voltameter in
ZOOLOGY AT THE BRITISH ASSOCIATION. 1898; (2) to determine the accuracy attainable in measure- BY arrangement between the organising committees, the ments with the silver voltameter (a) under conditions which presidents of the biological sections gave their are as regular as possible, and (b) with a variation of the addresses at different hours, so as to make it possible for factors in connection therewith. It was found (as at the members to attend them all
. The address in Section D National Physical Laboratory) that the differences obtained was delivered by Dr. Shipley on Friday, August 27. by Richards and by Schuster, attributable on the one hand The programme for Thursday, August 26, was opened by to the influence of the anode liquid, and on the other to Dr. E. Goodrich with a paper on the origin of the vertethat of the oxygen, could not, within the errors of observa- brates. The object of this paper was to show that none tion, be confirmed.
of the theories of the origin of vertebrates hitherto brought Particulars of the changes in shellacked manganin coils forward, deriving them from some existing class of the due to varying humidity were published in 1908. The invertebrates, was satisfactory, because the theories violated changes in question are so slight in the German climate the sound principles of phylogeny based on the combined as only to be of importance for resistances equal to or evidence of comparative anatomy and physiology, embryogreater than 100 ohms, and even then only for measure- logy and palæontology. This evidence enables us to trace ments of the highest precision. For resistance standards back the Gnathostomes to a primitive shark-like fish, the of 1000 and 10,000 ohms the changes during the summer Gnathostomes and Cyclostomes to a common form of muh of 1908 amounted to 5 parts in 100,000 only. By taking more uniformly segmented structure, and, finally, the the precaution of keeping resistances in a hygrostat of Craniata and Cephalochorda to an ancestor of very simple 50 per cent. humidity the constancy of all resistances up structure, without dermal skeleton and without pronounced to a 100,000-ohm coil was secured. A comparison of the cephalisation, whiclı probably became extinct even before mercury standards with the manganin coils is in hand. the Silurian age.
Various institutions (e.g. the National Physical Labora- Mr. C. L. Boulenger followed with a paper on certain tory, Teddington, and the Bureau of Standards, Wash- subcutaneous fat-bodies in Bufo. These structures are to ington) have issued specifications for the setting up of be found in a number of different species, and consist of standard cells, and detailed instructions are given for the masses of adipose tissue situated at the junction of the preparation of the mercurous sulphate. It is directed that hind-limbs with the trunk. this salt shall not be washed with water, but with dilute On Friday, August 27, after the presidential address, sulphuric acid or with a saturated solution of cadmium Prof. H. Jungersen read a paper, illustrated by lanternsulphate. The Reichsanstalt is of opinion that the manner slides, on the osteology of the Lophobranchii. The author of washing the preparation is without influence on the pointed out that the skeletons of these fishes have hitherto result. It follows from this that the same E.M.F. results been most unsatisfactorily examined, and the cranial strucwhether the salt be hydrolysed or not.
tures, especially the suspensory apparatus, the gill-arches In connection with the research on anode rays men- and the scapular arch, have been incorrectly interpreted by tioned in the last report, it was found that when in the all previous authors. In the skull, parietals and opisthoties presence of substances which emit intense anode rays the are wanting, the pterotics are greatly developed, reaching electro-negative bodies such as iodine, bromine, &c., con- below to the basioccipital, and preventing the exoccipitals siderably favour the formation of the rays. It was found from meeting the prootics. These two features, together that the red and blue fluorescent tints of glass which can with the prolongation of the anterior part of the skull be produced by slow kathodic rays can also be caused by | (mesethmoid and vomer), the Lophobranchii have in
common with the Solenostomida, the Fistulariidæ, the find suitable conditions. To account for such a distribuAulostomidæ, and the Centriscidæ, these families forming tion over the whole of the globe, it has been supposed with the Lophobranchii a natural group, the “Solen- that most species of Rotifera can be dried up and their ichthyes " of Regan.
bodies carried by the wind, as dust, for long distances, The scapular arch is cartilaginous to a much greater and then come to life again on landing in suitable surroundextent than is the case in other Teleosteans, but a small ings. This Mr. Rousselet showed to be a very erroneous ossified scapula is to be found as well as a coracoid. generalisation of the fact that a very few species of
The three anterior vertebræ are immovably joined bdelloid Rotifera, and in particular Philodina roseola, are together, their neural arches being firmly bound by sutures capable of secreting a gelatinous envelope in which they with long dentations; in addition, the two anterior ones can resist drought for many months, and come to life are fixed to the expanded clavicle. The vertebræ bearing again on being placed in water. The author's experience the interspinous bones for the dorsal fin are provided with has shown him that the vast majority of rotifers die secondary transverse processes behind the primary ones, immediately on being dried, and do not revive after comthus enlarging the surface which gives attachment to the plete desiccation ; but their eggs, and in particular their powerful muscles of the dorsal fin, the chief agent in resting eggs, can stand a prolonged state of desiccation swimming.
and also freezing, and can therefore readily be transported After a paper by Dr. S. Hadwen on Texas fever in by the wind or by aquatic birds and other animals, and cattle, and its cure by the use of drugs, the day's pro- will hatch when deposited in suitable pools of water. In gramme closed with the reports of the special committees his opinion it is by this means that the cosmopolitan dison grants.
tribution of the Rotifera over the world has in the course The meeting on Monday, August 30, was opened by of time been brought about. Prof. A. B. Macallum, who read a paper, illustrated by Dr. J. Pearson read a paper on the processes of autonumerous lantern-slides, on palæobiology and the age of tomy in the Crustacea, and Prof. H. Jungersen communithe earth.
cated an account, by Dr. J. Schmidt, of the distribution Prof. C. J. Patten followed with two papers :-(1) on of the fresh-water eels (Anguilla) throughout the world. the pre-nuptial plumage in Calidris arenaria, illustrated by The following papers were, in the absence of the authors, lantern-views of the sanderling at different periods ; (2) on taken as read :-Dr. F. A. Dixey, on the parallelism the germinal disc in naturally incubated eggs of Passer between the nymphaline genera Adelpha and Chlorippe ; domesticus. Due reflection of the facts that nests (or, in and Mr. W. J. Dakin, histology of the eye of Pecten. the case of those birds which make no nest, the soil on In the afternoon Mr. J. Stanley Gardiner delivered a which the eggs are deposited) vary to an extraordinary lecture on coral-reefs, illustrated by numerous lanternextent in their heat-retaining properties; that the protect- views. ing egg-shells vary strikingly, not only in their thickness, Two resolutions were passed by Section D during the but in their porosity and other structural peculiarities; meeting at Winnipeg : and, lastly, that avian embryos vary to a considerable (1) "The zoological section of the British Association extent as regards their vitality when heat is withdrawn wish to record their sense of the danger caused by the from the shell, has led the author to think that the method approach of the Norwegian rat, which threatens the wheat of studying avian embryology by means of the artificial industry of western Canada, and to urge the Governments incubator is not always the most trustworthy. He there- concerned take immediate steps to organise the fore described the changes which he observed during the extermination of this dangerous pest. first six hours in a clutch of naturally incubated eggs of (2)“ In view of the enormous importance of the fisheries the house-sparrow (Passer domesticus).
of Canada in connection with her prosperity and her rapidly The next paper, on the rôle of visual function in animal developing position as the great source of the food supply and human evolution, was, in the absence of the author, of the Empire, and appreciating the danger of exhaustion Dr. G. M. Gould, taken as read.
which menaces certain of the fisheries, the members of the Prof. S. H. Reynolds read a paper on the British zoological section of the British Association for the Pleistocene Canidæ. Three species are found, the wolf, Advancement of Science, now in meeting in Winnipeg, the fox, and the Arctic fox. There is no evidence of the desire to congratulate both the Dominion and the Provincial existence in Britain in Pleistocene times of any animal Governments upon the work already accomplished in conthat could be called a dog. The jaw described as Lycaonnection with the study of the food-fishes, upon the establishanglicus is thought by the author to be better regarded ment of a marine biological station on both the Atlantic as a somewhat abnormal wolf. While, apart from any and Pacific coasts, and upon the cooperation with the difference in size, the skull of a fox is readily distinguished Government of the United States in an International Comfrom that of a wolf or dog by the depressions in the post-mission from whose labours much may be expected. orbital processes of the frontals, it is extremely difficult, At the same time, the members of the section are of the if not impossible, to find any valid distinctive character opinion that further and more extensive efforts in all these between dogs and wolves. The most useful character, for directions are urgently needed if certain of the fisheries, which we are indebted to Studer, is the orbitofrontal angle. notably that of the Pacific salmon, are to be maintained He regards as belonging to wolves skulls in which this even at their present condition of productiveness. For the angle measures 40°-45°, and as belonging to dogs skulls framing of satisfactory and effective regulations for the in which the angle is greater than 45o. The author's utilisation and conservation of the food-fishes a complete measurements, while confirming Studer's contention that knowledge of their life-history is absolutely necessary, and the angle in question tends to be decidedly less in the wolf the section desires to impress on the Governments conthan in the dog, show that the distinction is not absolute, cerned the immediate need for an extensive prosecution of and cannot be relied on in all cases.
investigations along this line, for greater facilities for the The programme for the last day of the meeting, Tues- scientific study of the fisheries, especially those of the day, August 31, opened with a paper by Mr. C. F. Pacific coasts, and for a continued cooperation of the Rousselet, on the geographical distribution of Rotifera. Dominion Government with the governments of the The author showed that the results of recent investiga- provinces and also those of the United States in all efforts tions point more and more to the fact that the Rotifera looking towards the conservation of the fisheries, one of enjoy a cosmopolitan distribution, which is not limited to
the most valuable natural resources of Canada." continents, but extends to all places on the surface of the earth where suitable conditions prevail. Wherever search has extended in Europe, America, Africa, India, China,
GEOGRAPHY AT THE BRITISH Australia, and even the north and south polar regions,
ASSOCIATION. the same genera, and even species, have been met with, THIS section was presided over this year by Colonel Şir rotatorian fauna for any continent, zone, or region.
director-general of the Ordnance Survey of the United The very erratic appearance of rare or uncommon species Kingdom, and, as usual, the opening address dealt with in widely separated places seems to show that distance is matters of which the president had been made intimately no obstacle to their distribution, provided only that they cognisant through his life-work. After briefly referring to