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del Entomologo," written by Father Navas, and published last year by the Catholic Press of Barcelona. It contains concise directions to the beginner for collecting, preserving, and classifying insects. Neither old nor new methods have been overlooked, for a wellworn figure of a collector "beating" into a venerable type of umbrella faces a sectional drawing of the modern "Berlese funnel."
DR. ROLF WITTING continues to contribute a great deal of most valuable hydrographical information on the sea-waters in the neighbourhood of Finland. In addition to the Jahrbuch, 1913, of the Finländische Hydrographisch-Biologische Untersuchungen, No. 13, which contains the details of salinity, temperature, and current measurements obtained on the seasonal cruises and at particular stations, we have received special papers by him on the optical and chemical examination of the water samples and on the methods of determining traces of ammonia in sea-water, as well as a paper by Prof. K. M Levander on the plankton of the Tavastfjärd. The oceanographers of Finland are to be congratulated on the regularity and persistence with which this work has been maintained for a number of years upon a uniform plan, a persistence which has obtained for them a place in the forefront of the European countries which have been engaged in marine researches in recent years.
We have received from the British Museum (Natural History) a report by Dr. S. F. Harmer on Cetacea stranded on the British coasts during 1914. The arrangements made by the Board of Trade for reporting such strandings a couple of years or so ago have been continued, and in some respects amplified, a notable innovation being the dispatch of the lower jaws of the smaller species, and of a plate of whalebone in the case of the baleen-whales. Up to the outbreak of the war returns were received regularly, but afterwards, when coastguards had their hands full of other duties, there was a great falling-off in the returns, this being particularly the case during the period from August to mid-October, when the items should have been at their maximum. The whole annual record of strandings amounted only to fiftyseven, as compared with seventy-six in the previous year. It may now be regarded as definitely established that the porpoise is by far the most abundant of the smaller cetaceans visiting the British coasts, and it may be added that the series of lower jaws of this species received at the museum has enabled Dr. Harmer to make some valuable observations with regard to the rate of growth, wear, and variation of the teeth such observations indicating that a socalled species founded on such differences is invalid. Four records of the dolphin and the same number of the white-beaked dolphin are included in the list, which also comprises a Sowerby's beaked whale taken alive in September on the Wexford coast.
A RECENTLY published number of the Indian Journal of Medical Research (vol. ii., No. 3) begins with a memoir by Mrs. Helen Adie on the sporogony of Haemoproteus columbae, the "halteridium" parasite of the blood of the pigeon. The development was
studied in Lynchia maura, the hippoboscid fly which is a common parasite of pigeons, and well known to be the invertebrate host of the Hæmoproteus. Whereas, however, previous investigators had not been able to find any stage of the parasite more advanced than the ookinete or "vermicule" in the Lynchia, and were of opinion that the parasite was inoculated into the pigeon by the fly in this phase of its development, Mrs. Adie has found that the ookinete-stage is succeeded by a process of sporogony exactly similar to that of the malarial parasites, with oocyst and sporozoite stages, ending with vast numbers of sporozoites in the salivary glands of the fly. The author states that no blood-parasites other than the Hæmoproteus were to be found in the pigeons; this statement, if correct, disposes of the obvious criticism, that the sporogony seen might be that of some Proteosoma parasite of the birds. Mrs. Adie is much to be congratulated on having filled an important gap in the knowledge of the development of these parasites, and on having discovered a series of stages which had escaped the notice of such competent observers as the Sergent brothers and Aragao. It is to be regretted that all recent writers on the development of malarial parasites use the term "zygote" in an entirely incorrect manner; the term should be used to mean the body formed by the union of the two gametes, and should therefore be applied, in the present case, to the rounded stage preceding the ookinete, and not to the oocyst-stages following the ookinetestage.
ATTENTION may usefully be directed to a paper on the care of old trees, illustrated by plates, in the Kew Bulletin (No. 2, 1915), since this is a subject often sadly neglected by those in charge of our parks and gardens which contain historic or interesting trees. The questions of breakages by wind, injuries by fungi, proper watering, feeding, and mulching, and the proper treatment of wounds are dealt with fully.
MR. T. PETCH contributes to the Annals of the Royal Botanic Gardens, Peradeniya (No. vii., vol. v.), a useful preliminary note on the genera Hypocrella and Aschersonia, fungi parasitic on scale insects which he has studied in connection with the type specimens preserved in the principal European herbaria. As a result of his investigations Mr. Petch has been able to clear the ground for his full paper, to be illustrated, we hope, with the drawings, by setting out the synonymy of the species examined. The species of the western hemisphere, with the one exception of Hypocrella camerunensis, found in Brazil and Africa, are distinct from those of the eastern hemisphere.
THE description of new species of plants from China occupies the greater part of No. xxxviii. of vol. viii. of the Notes of the Royal Botanic Garden, Edinburgh, and are largely the result of Forrest's and Ward's collecting in western China. Among them are six new Rhododendrons to swell the long list of this important Chinese genus, and one of them, R. Wardii, W. W. Smith, with its large flowers, "slightly fleshy bright yellow with the faintest touch of crimson on interior at base," fills the heart of the cultivator with
an eager desire to introduce the species. Messrs. Lace and Smith also describe three Rhododendrons from Indo-Burma, two of which were previously but very imperfectly known; all three species are figured.
THE Kew Bulletin, No. 2, 1915, contains several papers dealing with systematic botany and matters of general botanical interest. Diospyros ebenaster, a widely cultivated tree in the tropics, often considered to be a native of the Philippine islands, is almost certainly indigenous in the West Indies, whence it has been introduced to other countries at a very early date. Mr. Sprague enumerates the sections of the South African species of Loranthus, the outcome of his work on the genus for the "Flora Capensis," and there are descriptions of twenty new plants, ten from Africa and ten from Australia, India, Malaya, etc. Of more general interest is a paper on the germination of coco-nuts, with reference particularly to the age of the trees from which seed nuts should be taken. There appears to be no reason, especially in the light of recent experiments in the island of Nevis, why nuts from good trees in their third year of bearing should not be used despite the prevalent beliefs usually held on the subject that to use such nuts is to court disaster. The doubts entertained recall the words of Sir Thomas Browne: "So these Traditions how low and ridiculous soever, will find suspition in some, doubt in others, and serve as tests or trials of Melancholy and superstitious tempers for ever."
THERE are few better Transactions than those of the Norfolk and Norwich Naturalists' Society, and their high place in science is well maintained by their latest publication, vol. ix., part v., 1913-14. The work in this goodly volume of some 200 pages is admirable : and we think that the members of the society receive a full return, or more than full, for their subscriptions. We would also congratulate the hon. secretary, Dr. Sydney Long, on the care which he has given to the editing of the volume. The president of the society, Miss Alice Geldart, in her address to the annual meeting, announced that the society has published the "Flora of Norfolk," edited by Mr. W. A. Nicholson. The subject of her address was the lives of some of the earlier Norfolk botanists; and it is a model of careful and sympathetic biography. Next comes Mr. Wormald's paper, well illustrated, on the courtship of ducks; then the valuable reports on that sanctuary of birds and of wild plants, Blakeney Point. Other monographs, of no less value, are contributed by Dr. Brenchley, Mr. Burrell and Mr. W. G. Clarke, and Mr. Rivière; and there is a wealth of shorter papers. Altogether, the volume deserves the highest praise as the publication of a county scientific society.
MR. E. MANCINI contributes an account of the Italian earthquake of January 13 to the Revue générale des Sciences, etc. (March 15, pp. 146-48). Most of the details contained in it have already appeared in our columns (vol. xciv., p. 565; vol. xcv., pp. 76-7). Mr. Mancini remarks that the exact position of the epicentre is still undetermined, but that,
according to Dr. Agamennone, there may have been two separate foci in action at, or nearly at, the same time (see NATURE, vol. xciv., p. 565). He estimates the total number of lives lost at more than 25,000. The number of persons saved at Avezzano was 2300 out of 13,000, so that the death-rate in that town must be reduced to 82 per cent.
A BIOGRAPHICAL notice of the late Prof. Adolfo Venturi appears in a recent number of the Rendiconti della R. Accademia dei Lincei (vol. xxiv., 1915, pp. 277-83). Born at Florence on September 22, 1852, he studied mathematics in the University of Pisa, obtaining his diploma in 1875. Shortly afterwards, he became mathematical teacher in the lyceum of Como, and in 1888 was appointed to the chair of geodesy in the University of Palermo. His work while at Como dealt mainly with the motion of the earth about its centre of gravity and the perturbations of comets and minor planets. At Palermo, he naturally turned his attention to geodetic problems, and afterwards to terrestrial refraction. Prof. Riccò in 1896 had begun a gravimetric survey of eastern Sicily, and this was extended by Venturi to the western half of the island. After a brief illness, Prof. Venturi died at Palermo on December 28, 1914.
MESSRS. EDWARD STANFORD, LTD., have issued Nos. 11 and 12 of their series of war maps. No. 11 shows the eastern theatre of operations, and includes Hungary, Galicia, Bukowina, Poland, and parts of the neighbouring areas. The map is on a scale of eighteen miles to the inch, and shows contours coloured on the layer system, which demonstrate clearly the Carpathian heights between the northern plain in Poland and the plain of Hungary. Railways, roads, rivers, and numerous towns and villages tend to facilitate reference in connection with the official communiqués. This very useful publication is 33 × 45 in. in size, and the price ranges from 7s. 6d. to 17s. 6d., according to style of mounting. No. 12 is devoted to the Dardanelles area of conflict; the sheet includes seven separate maps. There are plans of Constantinople, Smyrna, and Skutari; large-scale maps of the Dardanelles from Kum Kaleh to Gallipoli, and of the Bosphorus; a map of the Sea of Marmora and its entrances, and a map of Turkey-inEurope and the western portion of Asia Minor. The two latter maps show contour at intervals of 1000 ft., and indicate relief by colour shading.
SCIENTIFIC PAPER No. 239 from the Bureau of Standards contains a description of a vibration electrometer by Mr. H. L. Curtis, of the bureau. The needle of the instrument consists of a light aluminium vane, 2 cm. square, supported with its plane vertical by a bifilar suspension, which extends both above and below the vane. Two fixed plates, 1x2 cm., are placed on each side of the vane, with their planes also vertical. The distances of the plates from the vane can be varied from 0.5 to 10 mm. To obtain complete control of the damping the whole instrument is enclosed in a bell jar which can be exhausted. The vane is connected to a battery giving 240 volts, and the alternating electromotive force to be detected is applied to
the plates, which are cross connected, as in the quadrant electrometer. Resonance is secured by adjusting the tension or length of the suspension, and the deflections are read by the telescope and scale method. With the air pressure reduced to 0-005 mm. of mercury the deflection per volt at 50 cycles per second is 6 cm. on a scale at a metre distance, and the least current the instrument will detect is 10-11 ampere. The behaviour of the electrometer agrees very closely with the theory developed by the author.
TECHNOLOGIC PAPER NO. 41 of the Bureau of Standards, Washington, by R. S. McBride and J. D. Edwards, deals with the lead acetate test for hydrogen sulphide in illuminating gas, and is of interest here, as sulphuretted hydrogen is now the only impurity in coal gas officially controlled. pointed out that the various modes of testing in use are not all directed to the same end, since some of the tests are designed to detect as small traces of hydrogen sulphide as possible, while others aim to give a negative test when a permissible amount is not exceeded. The previous work of W. J. Dibdin and R. G. Grimwood, R. Forbes Carpenter, and C. J. Ramsburg, is described and criticised, and details of a new set of experiments are given in which some of the errors ascribed to the earlier work are avoided. The variations due to the kind of paper, concentration of lead acetate solution, preparation and condition of the paper, humidity of the gas, rate of flow and time of exposure, and the various forms of testing apparatus have been studied separately. Based on these results a method is recommended for use which is claimed to be quick and convenient, and gives reproducible results.
A RECENT publication among the Oxford pamphlets is by Prof. J. O. Arnold, the professor of metallurgy in the University of Sheffield, entitled "British and German Steel Metallurgy." It was inspired, as the opening sentences show, by an article by Prof. Rein, of the University of Vienna, on "Civilisation and 'Kultur.'" The pamphlet attempts to show (1) that German steel metallurgy owes far more to British inventors than British steel metallurgy owes to German inventors, and (2) that the steel department of the University of Sheffield has done work greatly superior to that of the corresponding department at Charlottenburg. The following claim bearing on the latter thesis may be quoted from the pamphlet as typical of the style :-"There are about twenty-nine constituents or sub-constituents of steel and iron. these, twenty-six have been discovered in Sheffield, the steelopolis of Great Britain; three in Middlesbrough, its ironopolis; and the record of Charlottenburg in this branch of research is absolutely blank." We confess to regretting that the author has by this publication placed himself in the category of those who desire to minimise the debt that British science owes to German science. It would have been better if the task had not been attempted.
THE Engineer for April 9 directs attention to some absurd British methods of dealing with drawings re
ceived from consulting and other engineers on the
THE ninth report of the Royal Commission on
distant from Serpentis, which star is further to the westward.
THE "SCIENTIFIC AMERICAN AND ASTRONOMY.-The Paris Observatory and its work is the subject of an interesting article to the Scientific American (March 13) by Prof. G. A. Hill, of the United States Naval Observatory. The author accompanies his text with two excellent reproductions showing the large transit circle and the eye end of the equatorial Coude. The history of this famous institution is briefly sketched, and special reference made to the lunar photographs taken by MM. Loewy and Puiseux. In the issue of the same journal for March 20, Abbé Th. Moreux describes the planet Saturn, its ring system, and the satellites, and accompanies his remarks with a large number of reproductions from early and late drawings. Such articles popularly written and finely illustrated render a great service in disseminating astronomical knowledge, and we hope to direct attention to similar contributions in future issues.
THE CHROMOSPHERIC SPECTRUM WITHOUT AN ECLIPSE. -In the March number of the Proceedings of the U.S. National Academy of Sciences, W. S. Adams and Cora G. Burwell describe briefly the results of an investigation of the flash spectrum without an eclipse in the region à 4800 and A 6600. The full paper will soon be published as No. 95 of the Contributions from the Mount Wilson Observatory. In the first place, it is interesting to record that the total number of lines measured upon the negatives taken without an eclipse is greater than that obtained from eclipse negatives. Thus Mitchell's beautiful chromospheric spectrum of 1905 showed 901 lines, while those here measured number 1027 lines. It is further pointed out that in the photographs taken without an eclipse the wave-lengths of the bright lines have been determined with reference to the dark lines at the limb. A comparison of 512 lines shows that the difference between the wavelengths of the bright lines and the dark lines at the limb gives a value -0'002 Angstrom. The preponderance of the negative sign in the case of the individual elements makes it fairly probable that this OF
quantity may be regarded as real. Reference is made also to the marked gain in accuracy for the Mount Wilson results, attributed notably to the greater linear scale of the photographs. Some peculiar characteristics of the dark line spectrum of the sun's limb as seen on the photographs of the flash spectrum are briefly decribed, and the identification of the elements to which these lines belong is suggested as a research of decided interest.
THE ROTATION OF NEBULA.-Prof. Percival Lowell has forwarded two very interesting photographs of the spectra of nebulæ taken by Dr. V. M. Slipher, both of which are briefly described by the latter. The first is the spectrum of Virgo nebula, N.G.C. 4594, taken in April, 1913, with an exposure of 30 hours, together with comparison spectra of vanadium and iron. It was from this photograph and two others, also taken in the same year, all of which showed the nebula lines inclined, that the first direct evidence that nebulæ rotate was secured. In the photograph sent the slit was placed east and west, and the rotation in the sense that brings the west side of the nebula towards the earth. In addition to their inclination the lines have a large displacement, which makes the solar band G nearly coincident with the iron line A 4326, thus indicating a velocity of recession of 1100 kilometres. Dr. Slipher remarks that this was far the highest velocity then known, but "further observations of nebulæ here have revealed others as high." The second photograph is of the spectrum of the Crab nebula, N.G.C. 1952, taken in February of the present year, with 18 hours' exposure, and similar comparison spectra. This is described as "the most remarkable nebula spectrum known." Upon a rather strong continuous background are found bright lines typical of gaseous nebulæ lines. Thus the lines AA 5007, 4959, 4861 (Hẞ), 4686, 4341 (Hy), seem to be present. The strange appearance of these bright lines is described as follows:-"They seem to be split into doubles, best seen in A 5007 and A 4861 (the inside components of λ 4959 and A 5007 would be blended). The distance between the components changes with the position in the nebula. It reminds one of the Zeeman effects in a non-uniform magnetic field and implies the origin to be within the atom. However, the maximum separation is quite enormous-40 tenthmetres. A plausible explanation of the spectrum as velocity effects has not occurred to me as yet."
EXPERIMENTAL STUDY OF THE
MECHANISM OF WRITING.
F recent years considerable advances have been made in the experimental study of the complex processes of reading and writing, mainly in the interests of a new experimental science, which is at present calling itself "experimental pedagogy," and at recent meetings of the British Association the Educational Science Section has devoted a good deal of attention to such work. In the Proceedings of the Royal Society of Edinburgh a further contribution to the experimental analysis of the writing process is made in a paper by Mr. James Drever, on the analytical study of the mechanism of writing.
Looked at from the outside, and regarded purely as a mechanical process, the writing act consists of certain movements and co-ordinations of movement of the fingers, hand, forearm, and shoulder. Of these the hand movements and the work of the fingers are the most important. By employing various pieces of comparatively simple apparatus it is possible to separate hand and finger movements, as well as to isolate for observation and study both the pressure of the fingers in holding the writing instrument and also the pressure placed upon the writing point.
To Prof. C. H. Judd, of Yale, we owe the original idea of a simple piece of apparatus which enables the experimenter to separate hand and finger movements. This apparatus consists essentially of an attachment for the fifth metacarpal, which carries a pencil or style for recording the movement of the hand. The origiral form of the apparatus was defective in several respects, but a modified form described in the above-mentioned paper seems to eliminate most of these defects. By comparing the record of the hand movement with the actual writing we can determine the part played by finger movement. should be noted, however, that there is one movement of the hand in writing which cannot be recorded in this way. That is the movement known as pronation -the movement round the axis of the wrist.
Records taken with Judd's apparatus yield several interesting results. Some writers use little, if any, finger movements, and most writers, when writing at maximum speed, and especially with the pencil, approximate to this type. Ordinarily, however, in careful adult writing in this country, all the finer work in the formation of the letters is due to finger movement, and this to a greater extent in pen writing than in pencil writing. As a rule the writers themselves are quite unconscious of such finger movements. In the writing of the child, who
is merely at the learning stage, there is little finger movement, but finger movements develop as facility is acquired.
The isolation of grip pressure in writing is secured
by an apparatus consisting essentially of a doublewalled rubber capsule, inserted into the pen or pencil holder to take the grip (Fig. 1). The space between the walls, and also the inner space, are filled with mercury. A capillary glass tube passes into the inner space, and its top is connected by means of rubber tubing in the usual way with recording tambour.
Any variations in
recording tambour. In Mr. Drever's apparatus the pen or pencil is attached to a receiving tambour, which forms the top of the pen or pencil holder (Fig. 2). This last form of apparatus is exceedingly simple and convenient for use with children.
The study of the point pressure curve has already yielded some interesting results, which bear not only upon education but also on the study of mental defects. In normal adult writing two types of pressure curve were early and easily distinguished, and it is possible to distinguish three. The first, which is known as the mas culine type, shows a single definite maximum of pressure for each word, and increased pressure with increased speed of writing (Fig. 3, IV.). The second, known as the feminine type, shows several maxima of pressure in each word, and diminished pressure with increased speed of writing. The third, which might be called the clerical or mechanical type, shows great uniformity of pressure
sure on the outer wall M N N N N N l m m
of the capsule are in this way transmitted to a the tambour and
graphically recorded by the marking lever on a smoked drum.
Very little work has hitherto been done in the study of grip pressure. The most striking feature in the grip pressure curve obtained is its rhythmical character (Fig. 3, VI). With the adult this rhythm is extremely regular, but it is absent in the earliest writing of children, first appearing about the age of eleven, and then with marked irregularities (Fig. 3, VII.). In writing with the pencil the grip pressure is siderably greater than in writing with the pen, and the difference between maxima and minima in the rhythm also greater. Finally,
there are in adult writing definite indications that a word or phrase is written with one total impulse.
I. to III. Point pressure tracings from children.
Time record in seconds by Jacquet Chronograph.
16. Child of six (first attempt at script). Words "A man can."
Ila. Pencil writing, and IIb. Pen writing of child of eight. Words "Moray House School," written twice in each case.
IV. and V. Point pressure tracings from adults. Time record in secs. by vibrating spring.
IVa. Pencil writing, ordinary rate. Words "Moray House School," written twice.
IV. Pencil writing by same subject, maximum rate. Words "Moray House School," written four times.
V. Pen writing, slow and fast. Words "Moray House School," written once slow and twice fast.
VI. and VII. Grip pressure tracings from adults and child of eleven. Time records for adults in secs. and for child
Several different forms of apparatus have been employed for obtaining a record of point pressure in writing. Continental investigators have employed a writing plate, either connected directly with a lever for marking on a smoked surface, or resting on an air cushion pneumatically connected to a
in each word, and practically no change of pressure with increased speed of writing; further, there is comparatively little increase of speed beyond the ordinary rate, and in some cases the speed actually