entirely hypothetical, as might have been shown at any time by stimulating the facial nerve in the skull, and observing the soft palate.

We have found that stimulation of the peripheral end of the divided facial nerve in the internal auditory meatus failed to cause even with most powerful currents the slightest movement of the soft palate, although the face was thrown into violent spasm. The true motor nerve supply of the levator palati is, according to our observations, the XIth nerve (vide infra).

IXth Nerve. Glossopharyngeal.-After exciting this nerve, in addition to the movements of the pharynx, which we attribute to the contraction of the stylopharyngeus, and possibly to the middle constrictor of the pharynx, we have observed certain movements of the palate, as follows :-(1) Stimulation of the nerve while beneath the stylo-hyoid ligament and uncut, gave in two instances elevation of the palate on the same side, and in one instance on both sides. We suppose that everyone will consider with us this movement to be reflex in origin, but we must add (2) that in one case we saw elevation of the palate to the same side when exciting the peripheral end of the cut nerve. In this latter case, perhaps, the result may be explained by the close neighbourhood of the pharyngeal plexus and the possible e cape of current thereto, and under any circumstances this is but a single exceptional observation, so that we lay no stress upon it. Finally we never saw movement of the soft palate when the glossopharyngeal nerve was stimulated within the cranial cavity.

Xth Nerve. Vagus. In stimulating the uncut nerve outside the skull, below the level of its junction with the hypoglossal, rhythmical movements of swallowing were produced, which occurred at the rate of twenty-five times in thirty-five seconds.

In one observation all the constrictors of the pharynx were thrown into action, when the peripheral end of the cut nerve was stimulated outside the skull.

The rhythmical movements of swallowing obtained by stimulating this nerve must be due to, of course, the simple reflex, the stimulus acting on the nerve in the centripetal direction, and that this was the case is proved by the fact that no movement was obtained when the peripheral end of the cut nerve was stimulated inside the skull.

The superior laryngeal branch on being stimulated gave rhythmical movements of swallowing at the rate of seventeen times in fifteen seconds, but when the nerve was cut and its peripheral end stimulated, only very slight movement was produced in the larynx, evidently by contraction of the crico-thyroid muscle.

XIth Nerve. Accessory to Vagus.-In discussing the motor functions of the VIIth nerve, we stated that the hitherto received idea of the soft palate being supplied by the facial nerve was, according to our observations, entirely erroneous. We find that the levator palati is supplied entirely by the XIth nerve.1 When the peripheral end of the cut nerve was stimulated inside the skull, elevation of the soft palate on the same side was invariably seen. The path by which the fibres from this nerve reach the palate is probably through the upper branch of the pharyngeal plexus.

XIIth Nerve. Hypoglossal.--When the entire nerve was excited outside the skull, just below the point where it is joined by the first cervical nerve, the tongue was flattened posteriorly on the same side, and the tip protruded also on the same side, while in no case was there any heaping up of the tongue.

At the same time the depressors of the hyoid bone were thrown into action, and in some cases this dragging downwards of the hyoid completely prevented the tongue from being protruded.

The movements described above were repeated without alteration when the peripheral end of the cut nerve was excited at the same place.

It must be particularly noted that the movements of the tongue were purely uni-lateral, and this was proved to be the case beyond doubt by two experiments, in which the tongue was divided longitudinally in the middle line to the hyoid bone, when the movements were seen to be entirely confined to the side stimulated.

When the cut nerve was excited within the skull a different result was obtained, the tongue was flattened behind, and protruded towards the same side, but there was no action in the depressors of the hyoid.

1 I desire to add here that Dr. Felix Semon, in the course of some experiments (unpublished), performed in conjunction with myself, found that in the dog the levator palati was innervated by the XIth nerve.-V. H.

It has always been held that the depressors of the hyoid bone receive their motor nerve supply from the hypoglossal through the descendens noni, but, as will be shown further on, according to our observation, these muscles are supplied by the first and second cervical nerves, and it is only when the hypoglossal is stimulated below the point where it is joined by the branch from the first cervical nerve, that any movement is produced in the depressors of the hyoid.

B. Spinal Division.

Our observations of the motor functions of the first three cervical nerves as regards their influence on the hyoidean muscles have been made when the nerves have been excited(a) In the spinal canal.

(6) In the neck immediately upon their exit from between the vertebral transverse processes.

The nerves in the spinal canal were separated from the spinal cord and thoroughly dried, the efficacy of the precautions taken against spread being evidenced by the difference in result obtained by exciting each root.

The effects obtained by the methods a and b were identical. Ist Cervical Nerve. Branch of Union with the Hypoglossal.In the description of the XIIth cranial nerve, we have stated as the result of our experiments that the depressors of the hyoid bone are not thrown into action when this nerve is stimulated within the skull. On carefully dissecting out the branch from the Ist cervical nerve to the hypoglossal we find on excitation of it that hyoid bone are strongly contracted. there is no movement in the tongue, but the depressors of the Of these muscles the sterno-hyoid and sterno-thyroid were always especially affected, while the omo-hyoid was less frequently seen to contract and in some cases not at all. In the cases where this muscle contracted, in one experiment the anterior belly alone acted, and when both bellies contracted the movement in the anterior was in excess of the posterior.

IInd Cervical.

Branch to the Descendens Noni.-On stimu lating this nerve the depressors of the hyoid were thrown into action, but the muscles involved were not affected in the same way as was the case with the Ist cervical nerve. The muscle which was most constantly set in action by excitation of the IInd cervical nerve was the omo-hyoid and especially its posterior belly. The sterno-hyoid and sterno-thyroid also took part in depressing the hyoid bone, but it was especially remarked in half the cases, that their action was notably less powerful than that of the omo-hyoid. In one experiment in which a very weak current was employed, the omo-hyoid was alone seen to contract. We are consequently led to conclude that while the sterno-hyoid, sterno-thyroid, and omo-hyoid muscles are all set in action by excitation of the Ist and IInd cervical nerves, the first two muscles are relatively supplied by the former nerve, while the IInd nerve is especially connected with the omo-hyoid muscle.

Descendens Noni.-We prefer to mention here the results of exciting this nerve, inasmuch as we regard its motor fibres to be derived entirely from the Ist and IInd cervical nerves. This nerve (ordinarily regarded as a branch of the XIIth cranial), when stimulated above its junction with the branch from the IInd cervical nerve, produced contraction of the sterno-hyoid and sterno-thyroid muscles, and where the current employed was weak there was no contraction of the omo-hyoid, but this movement was superadded on increasing the strength of the

current.

We ought here to mention the opinion held by Volkmann (loc. cit.) that fibres ascend to the hypoglossal from the spinal rami communicantes by the descendens noni.

IIIrd Cervical Nerve. -On stimulating the branch from this nerve, which forms the IInd cervical nerve just before the ansa thus formed is connected to the descendens noni, there was no action seen in the depressor of the hyoid bone; it therefore seems certain that these muscles are supplied with motor fibres solely by the branches from the Ist and IInd cervical nerves.

June 14.-" On Meldrum's Rules for Handling Ships in the Southern Indian Ocean." By Hon. Ralph Abercromby, F. R. Met. Soc. Communicated by R. H. Scott, F.R.S. The results of this paper may be summarized as follows:The author examines critically certain rules given by Mr. C. Meldrum for handling ships during hurricanes in the South Indian Ocean, by means both of published observations and from personal inspection of many unpublished records in the Observatory at Mauritius. The result confirms the value of

Mr. Meldrum's rules; and the author then develops certain explanations, which have been partially given by Meldrum, adds slightly to the rules for handling ships, and correlates the whole with the modern methods of meteorology.

As an example, a hurricane is taken which blew near Mauritius on February 11, 12, and 13, 1861, and the history of every ship to which the rules might apply is minutely investigated. The result, dividing Meldrum's rules shortly into three parts, is as follows:

Rule 1. Lie to with increasing south-east wind till the barometer has fallen 6-10ths of an inch. Seven cases, rule right in every case.

Rule 2. Run to north-west when the barometer has fallen 6-10ths of an inch. Three cases, two failures, one success.

Rule 3. Lie to with increasing north-east or east wind, and a falling barometer. Seven cases, rule right in every instance.

Rule 2 was exceptionally unfortunate in this case, as the path of the central vortex moved in a very uncommon and irregular manner. At the same time, in any case, it appears to be about equally hazardous to follow this rule or to remain hove to.

An

The following new statements are then examined in detail :-The shape of all hurricanes is usually oval, not circular. elaborate examination is made of hurricanes on 60 different days, in 18 different tropical cyclones in various parts of the world, with the following results :

:

(1) Out of 60 days, cyclones were apparently circular on only four occasions, and then the materials are very scanty.

(2) The shape was oval on the remaining 56 days, but the ratio of the longer and shorter diameter of the ovals very rarely exceeded 2 to I.

(3) The centres of the cyclones were usually displaced towards some one side. No rule can be laid down for the direction of displacement, and in fact the direction varies during the progress of the same cyclone. The core of a hurricane is nearly as oval as any other portion.

(4) The longer diameter of the ovals may lie at any angle with reference to the path of the cyclone; but a considerable proportion lie nearly in the same line as the direction of the path.

(5) The association of wind with the oval form is such that the direction of the wind is usually more or less along the isobars, and more or less incurved. This is the almost invariable relation of wind to isobars all over the world.

From an examination of the whole it is proved conclusively that no rule is possible for determining more than approximately the position of the central vortex of a cyclone by any observations at a single station.

The relation of a hurricane to the south-east trade is then discussed, and it is shown that there is always what may be called " a belt of intensified trade wind" on the southern side of a cyclone, while the hurricane is moving westwards. In this belt a ship experiences increasing south-east winds and squalls of rain, with a falling barometer, but is not within the true storm field. The difficulties and uncertainties as to handling a ship in this belt are greatly increased by the facts that the longer diameter of the oval form of the cyclones usually lies east and west, and that there is no means of telling towards which side of the oval the vortex is displaced.

The greater incurvature of the wind in rear than in front of hurricanes in the Southern Indian Ocean is next considered, and then facts are collected from other hurricane countries confirmatory of Meldrum's rules for the Mauritius.

Knipping and Doberck in the China Seas find little incurvature of the wind in front, but much in rear of typhoons.

Mr. Willson finds in the Bay of Bengal that north-east winds prevail over many degrees of longitude to the north, i.e. in front a cyclone; and this is analogous to the belt of intensified trade so characteristic of Mauritius hurricanes.

Padre Viñez finds at Havana that the incurvature of hurricane winds is very slight in front, and very great in rear.

The author then details further researches on the nature of cyclones, which bear on the rules for handling ships.

(1) Indications derived from the form and motion of clouds. It is shown that the direction of the lower clouds is usually more nearly eight points from the bearing of the vortex than the surface wind; but as the direction varies with the height of the clouds, and as this height can only be estimated, this fact is not of much value.

(2) Looking at the vertical succession of wind currents, if the march of the upper clouds over the south-east trade is more from

the east, then the cyclone will pass to the north of the observer but if the upper clouds move more from the south than the surface wind, then the hurricane will pass to the south of the observer.

(3) As to the form and position of clouds: so soon as the upper regions commence to be covered, the direction in which the cirrus veil is densest gives approximately the bearing of the Vortex. Later on, the characteristic cloud bank of the hurricaneappears, and the greatest and heaviest mass of the bank will appear sensibly in the direction of the vortex.

The irregular motion of the centre of a cyclone is next discussed, and it is shown that the centre often twists and sways about, in some cases even describing a small loop.

From this and other facts it is shown that the attempts which have been made

(1) To estimate the track of a cyclone by projection.

(2) To estimate the distance of a ship from the vortex, either by taking into account the entire absolute fall, or by noting the rate of fall, can lead to no useful result.

A series of revised rules for handling ships in hurricanes is given. Comparing these with the older onts it will be remarked

(1) That the rule for finding approximately the bearing of the vortex is slightly modified.

(2) That the great rules of the "laying to" tacks remain unaltered.

(3) That the greatest improvement is the recognition of the position and nature of the belt of intensified trade wind on the dangerous side of a hurricane, where a ship experiences increas ing wind, without change of direction, and a falling barometer. The old idea that such conditions show that a vessel is then necessarily exactly on the line of advance of a hurricane is erroneous. She may, but she need not be; and under no circumstances should she run till the barometer has fallen at least 6-10ths of an inch.

(4) There are certain rules which hold for all hurricanes; but every district has a special series, due to its own local peculiari ties. Those for the South Indian Ocean are given in this paper.

=

PARIS.

Academy of Sciences, July 23.-M. Janssen, President, in the chair.-The President announced the death, on July 19, of M. H. Debray, member of the Section of Chemistry, whose name will always be remembered in connection with the laws determining the tension of dissociation, the density of the vapour of sulphur, and other researches throwing much light on inany obscure chemical phenomena.-Note on target practice, by M. J. Bertrand. In continuation of his previous communication (Comptes rendus of February 6, 1888), the author here shows that the actual results of 1000 experimental shots correspond closely with the theory as expressed by the general equation k'x' + 2λxy + k'y' H. The practice was at a distance of 200 metres with ten rifles of like model, each marksman firing ten shots with each rifle.-Remarks on the quantitative analysis of nitrogen in vegetable soil, by MM. Berthelot and G. André. The analysis of nitrogen in ground containing nitrates presents some apparent difficulty. But the results of the researches here described show that in the case of ground poor in nitrates, the analysis may be safely and rapidly executed with a blend of lime and soda.-On the luminous bridges observed during the transits and occultations of the satellites of Jupiter, by M. Ch. André. As in the transits of Venus, these optical phenomena are here shown to be entirely due to the optical surfaces of the instruments modifying the direction of the luminous waves. They are, in fact, a result of diffraction in the instruments of observation.-Measurement of the coefficients of thermic conductibility for metals, by M. Alphonse Berget. The author here applies to red copper, brass, and iron, the same method he has already adopted for mercury (Comptes rendus, July 25, 1887, and July 16, 1888), with the following results: red copper, k = 10405; brass, k = 0 2625; iron, k = 0.1587.-Magnetic determinations in the basin of the West Mediterranean, by M. Th. Moureaux. Having been charged by the Minister of Public Instruction to collect the elements needed for the preparation of magnetic charts for this region, the author obtained in the period from April 19 to June 25, 1887, as many as ninety measures of declination and fiftynine of inclination for fifty-two stations. The results are here tabulated for these stations, of which four are in Corsica, three in Italy, two in Malta, one in Tripoli, seven in Tunisia, twenty

five in Algeria, one in Morocco, eight in Spain, and one in France. In a future communication will be given the magnetic charts constructed from these observations.—Analysis of the Nile waters, by M. A. Muntz. At the request of M. Antoine d'Abbadie, the author has examined several specimens with a view to determining the proportion of nitrates contained in these marvellously fertilizing waters. The results show that, while the proportion is variable, it does not exceed or even equal that found in the Seine and some other rivers. The analysis gives 4'02 mgr. per litre for nitric acid, which is derived partly from the soil, partly from the tropical rains which cause the periodical floods. The nitrates are not regarded as the chief cause of the great fertility of Egypt, which is more probably due to the chemical properties of the sedimentary matter deposited at each recurring inundation.- Researches on some salts of rhodium, by M. E. Leidié. The author here determines the constituents and formulas of the chloronitrate of rhodium and ammonia, the sulphate of rhodium sesquioxide, the oxalates of rhodium and potassium, of rhodium and sodium, of rhodium and ammonium, and of rhodium and barium.-On a new method of quantitative analysis for the lithine contained in a large number of mineral waters, by M. A. Carnot. The process here described is effected by means of the fluorides, and is based especially on their different degrees of solubility.-On the chloride, bromide, and sulphide of yttrium and sodium, by M. A. Duboin. The paper deals with the preparation and properties of the crystallized anhydrous chloride and bromide of yttrium, and the crystallized sulphide of yttrium and sodium.-On the quantitative analysis of glycerine by oxidation, by M. Victor Planchon. A detailed account is given (with further applications) of Messrs. Fox and Wanklyn's new process of analysis, based on the fact that glycerine, oxidized by the permanganate of potassa in a strong alkaline solution, is transformed to water, carbonic acid, and oxalic acid, according to the equation given in the Chemical News of January 8, 1886.- On anagyrine, by MM. E. Hardly and N. Gallois. The authors claim to have first discovered this extract of Anagyris fœtida, a poisonous leguminous plant ranging over the whole of the Mediterranean basin. They here describe its toxic properties, and determine the formula of anagyrine as C1HNO-Action of aniline on epichlorhydrine, by M. Ad. Fauconnier. Some months ago the author announced that he had obtained by the action of aniline on epichlorhydrine an oleaginous base, the chlorhydrate of which corresponds to the formula C15H20N,CO. He has since prepared this base in the crystallized state, and has also obtained some derivatives, which have enabled him to determine its constitution and true formula, C3H5(OH)(NH. CH3)2. Instead of dianilglycerine, as first suggested, he now proposes to call this base oxipropylenediphenyldiamine, which has the advantage of indicating its composition.-M. Pierre Zalocostas describes the constitution of spongine; MM. Arm. Gautier and L. Mourgues de l with the volatile alkaloids of cod-liver oil (butylamine, amylamine, hexylamine, dihydrolutidine); M. Massol gives a process for neutralizing malonic acid by means of the soluble bases; and M. H. Moissan describes the method of preparation and the properties of the fluoride of ethyl.

BERLIN.

The

Physiological Society, July 20.-Prof. du Bois-Reymond, President, in the chair.-Dr. Benda explained his views on the structure of striated muscle-fibres in connection with the statements recently laid before the Society by van Gehnchten. He took as his starting-point the wing-muscles of insects, which are composed of fibrille permeated by transverse partitions; each division of the fibre consists of a hollow cylinder of isotropic substance filled with contractile anisotropic material. latter shrinks under the influence of reagents, leaving above and below a disk of isotropic substance. In the muscles of the body in insects, and in those of the higher animals, the isotropic disks of neighbouring fibrilla are fused into continuous layers, between which the small cylinders of anisotropic substance run perpendicularly. When the muscles are resolved by the action of reagents into Bowman's disks, the cleavage of the fibrils takes place either across the anisotropic cylinders or the isotropic disks.--Dr. Heymans spoke on the relative toxicity of oxalic, malonic, succinic, and methyl-succinic acids, and of their sodium salts. He had been requested by Prof. Henry, who had studied the chemical and physical properties of these acids, to investigate the relative toxic action of this series of acids, and had found that the strongest acid—namely, oxalic—was the most poisonous.

One milligramme of this acid sufficed to kill a frog; of malonic acid, whose physiological action, as well as that of methyl-succinic acid, had not been investigated, 2 to 3 mgr. were necessary; of succinic acid, 3 to 4 mgr.; and of methyl-succinic acid, 6 to 7 mgr. The toxic action of the acids diminished thus as the molecular weight increased. When the sodium salts of these acids were used instead of the free acids, the toxicity was the same in the case of oxalic acid, but was much less in the case of the other three acids.-Dr. Sklarek gave an account of the recently published observations of Weismann and Ischikawa on partial impregnation of the Daphnidæ.

BOOKS, PAMPHLETS, and SERIALS RECEIVED.

Symons's British Rainfall 1887: G. J. Symons (Stanford).—Medieval Researches from Eastern Asiatic Sources, 2 vols. : E. Bretschneider (Trübnerì, -My Microscope, second edition: by a Quekett Club Man (Roper and Drowley).The Fauna of British India, Mammalia: W. T. Blanford (Taylor and Francis).-Schriften der Physikalisch-Ökonomischen Gesellschaf zu Königsberg i. Pr., 1887 (Königsberg).-Maps Nos. 3 to 7 to accompany Annual Report of the Geological and Natural History Survey of Canadi, vol. ii. 1886 (Dawson, Montreal).-Fauna der Gaskohle und der Kalkstee der Permformation Böhmens; Band ii. Heft 3, Die Lurchfische, Dprici Dr. Ant. Fritsch (Prag).-Beobachtungs-Ergebnisse der Norwegischen Polarstation Bossekop in Alten, ii. Theil (Grondahl, Christiania).-The Education of the Imagination: C. H. Hinton (Sonnenschein).—Many Dimensions, C. H. Hinton (Sonnenschein).-Die Süsswasserbry zoe Böhmens: J. Kafka (Prag).-Archives Italiennes de Biologie, Tome x Fasc. i. (Turin).-Journal of the Trenton Natural History Society, No. (Trenton, N.J.).-Bulletin de la Société Impériale des Naturalistes de Moscou, No. 2, 1888 (Moscou).-Transactions of the New Zealand Institute vol. xx., 1887.

Elementary Trigonometry. By the same Author. Fifth

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