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corresponding points of tho two retinal might continue on the same level when the head was inclined to either side. Dr. Ashe considered that this effect could only he produced with reference to a single pair of points in the retina: at any one moment, and that only at the expense of an increased alteration in tho level of every other pair of corresponding points. But he considered the attainment of this ohject unnecessary, inasmuch as any corresponding pair of points changed their level only with reference to the level of the earth's surface, and not ■with reference to the point looked at; this point, therefore, with tho two on the retinas, would remain in the same relative position notwithstanding the rotation of the plane containing them. Hence Dr. Asne considered that tho function of these muscles was yet to be assigned; while, on the other hand, a known function existed, capable of being voluntarily discharged, for the exercise of which no voluntary muscle had been assigned, namely, the adjustment of the focal distance of the eve. It had been considered that the ciliary muscle effected this by compressing the globe. No doubt tho action of the ciliary muscle might cause short-sightedness, and this defect had recently been remedied by its division ; but the ciliary musclo consisted of unstriped fibres, and its action must therefore be involuntary, which "was also demonstrated by the fact that the power of voluntary adjustment ofthe focal distance was not destroyed by its division. Dr. Ashe considered that the position of the obliqui was such that, acting together, and not separately as generally supposed, they would compress the globe of the eye, as the ciliary muscle might do involuntarily, and thus increase its refractive power by augmenting the anteroposterior axis. A diminution of focal distance would hence result. The retina would he thrown backwards by the same action, and its power of receiving a distinct image from a near object enhanced considerably thereby. The elasticity of the sclerotic coat would increase the focal distance again on the cessation of the voluntary action of these muscles. This view was confirmed by the fact that a person was conscious of a voluntary effort in adjusting tho sight to an object placed very near the eye, much more so than he would be to any eflbrt in looking at a distant object. It had been supposed that the four recti muscles, acting together, might compress the globe and cause a shortening ofthe focal distance; Dr. Ashe considered that the only effect of such a cooperation would be to draw the eyeball back into the orbit, and, if anything, rather diminish the antero-posterior diameter of the globe; certainly they could not increase it unless thev had osseous attachments anteriorly as well as posteriorly. But it had been demonstrated that the muscular fibres of tho obliqm were continuous quite round the eyeball; and hence if they were to act together, as Dr. Ashe suggested, their effect would undoubtedly be to increase the antero-posterior diameter of the globe. To correspond with such a diminishing of the focal distance a slight approximation of the antero-posterior axes of the eyeballs would be necessary, and were this to bo accomplished by the same mechanism the requisite correlation would be established between the two actions. This would be effected by the muscles in question if the point where their actions balanced each other were placed a very little anterior to that circumference of the eyeball which should pass through their fixed attachments, and this Dr. Ashe considered was exactly the position of their insertion into the sclerotic.

On voluntarily shortening the focal distance the pupil might be observed to contract, relaxing again when the focal distance was elongated; this seemed to corroborate Dr. Ashe's views, since the inferior obliquns and the circular fibres of tho iris were both supplied by the third nerve, and might be simultaneously affected by its action.

In experimenting on the dead body, Dr. Ashe had found that, by the sense of touch, a distinct elongation of the antero-posterior axis of the eyeball could be recognized on drawing at once on the two obliqui; he had found the sense of touch the most delicate indication of the alteration.

On the Scientific Cultivation of Salmon FisJierics. By Thomas Ashwortii, of Clieadle. The main objects of this paper were to show the great value of salmon-fisheries, how they have'been neglected in England, and how they might be improved. Tho produce of the English fisheries has fallen so low, that it has been estimated noi to exceed 10,000/. per annum, and this including the fisheries of Wales, while the money value of the Irish, according to the reports of the Commissioners of Fisheries, is not less than 300,000/. yearly; one fishery in Scotland, that of the Duke of Itiehmond in the Spey, is said to return to his Grace 12,000/. annually-. Tie author, in illustration of what may he accomplished for the improvement of s&lmca rivers, describes what has been done at his fishery in Ualway, and the results. In the short spaco of ten years the river has been rendered ten times more productive. During the present season as many as 3000 salmon have been taken with the rod. This great improvement has been chiefly owing to the great care taken in preserving the streams during the breeding-season, at an expenditure of 500/., ami by introducing young salmon, artificially bred, into streams fitted for them, but from which the fish had before been excluded owing to impediments preventing access from the sea. These impediments have cither been removed or avoided by mean* of ladders so constructed as to render the passage to and from the sea easy. A striking example is given by him of a river in Ireland converted into an excellent salmon river by means of ladders. This river is in county Sligo, the property of Mr. Edward Cooper. The ladders are over a fall of about 40 feet. So productive has this river, beloro barren, become, that in July last as many as 1000 salmon were captured in one week.

An Attempt to show that every Jiving Structure consists of Matter which is the Seat of Vital Actions, ami Matter in which Physical and Chemical Changes alone take place. By Professor Beale, F.RJ3.

The object of the author was to show that every living structure was composed of matter that was "living" and matter that had ceased to "live "—of "germinal matter" and "formed material." The first was alone the. seat of purely vital phenomena, while in the formed material physical and chemical changea alone occurred. It was not possible to form any notion of the chemical relation of the elements of living matter. Neither could we obtain evidence as to the chemical character of the compounds of which living matter was composed. We could not obtain living matter in solution, and separate it again, as we could crystalline substances. The. instant we commenced its chemical examination the particles ceased to be living, and the moment they ceased to live the elements combined to form certain compounds. The compounds did not exist as such in the living matter, but were formed the moment death took nlaco. To understand those views, it is necessary to be acquainted with Dr. Bcale s definition of the structure of a "cell."

At tho last Meeting of the British Association, in Manchester, the author had endeavoured to prove that every "cell," or "elementary" part of a tissue, consisted of matter m two states—forming, growing, active, within; and externally of matter which had been in the first state, but was now formed, and had ceased to be active. The latter coidd be changed by external conditions, &c, but it had lost all inherent active powers of changing itself, or of communicating its powers to inanimate matter. All pabulum (nutrient matter) which was to nourish a living organism must come into contact with the living or germinal matter. Then, and not till then, it acquires the same properties; so that the living matter has increased in quantity in consequence of the inanimate pabulum, or certain of its elements, being converted into this living matter. Such a change never occurred in inanimate matter unless living matter were present. The greater the facility with which the inanimate pabulum camo into contact with the living matter, the faster this increased. No matter how abundant tho pabulum might be, if tho living matter were surrounded by a thick layer of formed material, the living matter would increase but slowly.

It may be next inquired, What takes place during life in the smallest living independent particle, which consists of an envelope of formed lifeless matter, with living germinal matter, within?

1. Pabulum passes through the formed material, enters the living particles, and reaching their centre, some of its constituents become living. Thus the quantity of the living matter is increased.

2. The new particles tend to move outwards from the centre where they became

living, preceded by others which became living before them, and succeeded by new ones. Thus, during the life of a spherical particle, new centres are continually appearing in pre-existing centres.

ii. The oldest particles on the circumference of the spherule, having passed through various stages of existence in moving outwards from the centre, gradually lose the power of animating lifeless particles, and becoino resolved into formed material, which is destitute of the power of increasing itself, and is no longer living.

4. The new-formed material is being produced upon the inner surface of that already formed—that is, in contact with the germinal matter: so that, passing from within outwards, we have (a) germinal matter; (b) imperfectly developed formed material; (c) fully develojxd formed material. The germinal matter exhibits in cases a central portion (nucleus), within which may be one or more portions with many circular outline (nucleoli), and within theso smaller particles are often to be made out (nuclcoluli). Passing from within outwards are several zones, the innermost being most intensely coloured by carmine.

The thickness of the formed material must gradually increase unless the oldest part which is outside is removed as fast as new-formed material is produced; in the latter case we should have (d) disintegrating formed material.

The conversion of inanimate matter into living matter, and the conversion of living matter into formed material, aro continually taking place during life. The formed material, having been produced, is passive. It may be changed or altered, but it has no inherent powers of compelling the elements of matter to assume certain fixed relations to each other, like the germinal matter. It has ceased to live.

All the work performed by an organism during its life depends upon the action of certain agents upon this formed material. All these changes aro physical and chemical, and can be caused to continue after the organism is dead; but the fonned material itself can never be produced artificiallj', because its composition and properties depend upon the particles of germinal matter from which it was produced, and these derived their powers from pre-existing living particles, and these from their predecessors, and so on, back to the first living particle of that particular kind which was created. We can cause the destructive changes to continue after death; but the constructive changes cease with life, and cannot be imitated artificially.

The movements of living particles from centres, and the continual formation of new centres within pre-existing centres—the power of inducing similar changes in particles otherwise incapable of undergoing change—the progressive modifications taking place in a definite order, which end at last in the formation of passive substances having properties and chemical composition totally different from those of the pabulum on the one hand, and those of the living particleB themselves on the other,—constitute a series of phenomena which occur in every different kind of living matter, and in living matter alone. They cannot be explained in the present state of knowledge by physical and chemical actions, and they may still be fairly termed vital phenomena, in contradistinction to those purely physical and chemical changes which occur in the formed material.

Living matter always possesses the power of increase and formation, and these processes of increaso of the living matter, and its conversion into formed material, take place respectively under different circumstances. The conditions favourable to the increase of the living matter are not favourable to the production of formed material. Living matter may increase very rapidly, but the production of fonned material is comparatively a slow process. All those tissues which in their perfect state are composed of much formed material in proportion to the germinal matter, grow slowly. During the earlier periods of their existence their growth was more rapid.

When a mass of germinal matter becomes surrounded with a thick layer of formed material, change, as would be supposed, goes on very slowly. The pabulum passes slowly through the formed material, and in small quantity, so that very little germinal matter is produced. The conversion of germinal matter into formed matenal, however, still proceeds until only a very small quantity remains living, surrounded on all sides oy a thick, passive, and perhaps nearly impermeable envclopc. But suppose this envelope be ruptured, or softened, so that nutri-::matter obtains more ready access to the living matter within, what happen r The germinal or living matter rapidly increases, and may even grow at the expae? of the Eoftened envelopo itsell. Masses of living matter are formed in grts number, divide and subdivide, and perhaps multiply enormously, forming a s& mass, which may continue to increase for a time, but is incapable of lasti?. The conditions favourable for the regular conversion of the outer particles of eatk mass into formed material are not present, and the whole mass may die mi uudergo disintegration and removal. Very many changes occurring- in "tissue h disease may be explained bv these views. The power of living matter to gw^ infinitely is restricted by the conditions imder which it is placed. Konmlly, growth may be slow; but if the restrictions be to some extent removed, thee ■ nbnormal freedom of growth mav directly occur. This is exactly what happen; in the process of inflammation. The germinal matter of the normal cells is nwR freely supplied with nutrient matter, and this often depends upon actual rupture of the envelope of formed material. These views, it will be observed, explain tie phenomena of nutrition, growth, secretion, &c, without supposing any pecular attractive power in the cell-wall, or any mysterious agency in its structure or m the nucleus; indeed, the existence of the cell, as it is generally defined, is dispensed with altogether. The author's " cell" is a mass of living matter surroundi-l by matter which had ceased to live, and which, like other inanimate matter, mav bo changed by physical and chemical agents. He reduces "the action of tie cell" to the motion of living particles from centres where they become living, their passing through definite stages of existence, and their being ultimately resolved into substances exhibiting special properties, but lifeless. So he would explain the phenomena of inflammation, without resorting to the hypothesis of irritation, exaggerated action from external stimulation, &c.

According to the author's view, the most wonderful changes occur at the moment when the pabulum readies the living centre, where its properties become completely changed, and where it commences its new course of existence. To account for the new powers which the particles have acquired, the author is compelled to assume the existence of a special force or power which can only be derived from particles which already possessed this power. Ho assumes that this power compels the elements of the pabulum to take up new and forced relations to each other, while, as they gradually cease to bo under its influence, the elements resume their ordinarv attractions, and special compounds are formed—the nature of the compound depending, therefore, upon the relations w hich the elements were constrained to take up during tho living state. Hence he maintains that rital pmcer exists in the particles of living or germinal matter, while the formed matter around this is destitute of vital power, and is only influenced bv physical and chemical forces; and he thinks that while matter is in the state of living or germinal matter, it is in a temporary condition which is distinct and peculiar, and cannot be compared with any other state in which matter is known to exist. It is very remarkable that matter in this temporary condition exhibits the same appearance in all living beings, and possesses constantly an acid reaction. When set free, a mass always assumes a spherical form, and the smallest particles to be seen are still spherical. No one could distinguish by microscopical examination the "germinal matter" of one tissue from that of another, nor the germinal matter of one of the lowest, shnplat organisms from that of man. And yet, although the germinal matter of all structures appears to bo tho same, it differs most wonderfully in power as seen in the results of its life. The formed material, on the other hand, exhibits, as we all know, differences of structure easily demonstrated, and differences of propertv familiar to every one; these differences being due to vital powers existing in the matter when in its previous state of germinal matter.

Some additional Observations on the Coloured Fluid or Blood of the Common
Earthworm (Lumbricus terrestris). By John Dayt, M.D.. F.R.S., $e.
In this paper, supplementary to a former ono on the same subject, the author, by
varied experiments, some made in vacuo, some made in different gases, has en-

[graphic]

deftvoured to prove that the red fluid of the Earthworm is a receptacle for oxygen, and is thus subservient to the aeration or respiration of the animal.

Some Observations on the Vitality of Fishes, as tested by Increase of Temperature. By John Davy, M.D., F.R.S., &c.

The experiments described by the author were made on eleven different species of fish of our lakes and rivers, of which the several kinds of Salmonida? were of the number. The results were that a temperature of water between 80 degrees and 100 dejrrees was fatal to each kind. The Salmouidre were those which were most readily affected by elevation of temperature, the other species bearing it according to their kind somewhat better. The results generally were pointed out as of some interest in relation to the habitats of different itinds of fish, and also as tending to prove that the accounts given by travellers of fishes existing in hot springs are exaggerated, and not founded on accurate observation.

On the Question whether the Oxide of Arsenic, taken in very minute quantities for a long period, is Injurious to Man. By John Davy, M.D., F.R.S., $e.

In this paper the author gavo an account of a small mountain stream in Cumberland, Whitbeck by name, which contains a minute quantity of arsenic, and which has from time immemorial been used by the inhabitants of an adjoining village, without any marked effect, either bad or good, on man and other animals, with the exception of ducks, to which birds the feeding in it has proved fatal. The author attributed the innocuity of the stream to two circumstances: first, the extremely minute quantity of arsenic present; and, secondly, the little tendency that arsenic has to accumulate in the organs of animals—the duck probably having less eliminating power than others, lie mentioned instances in which arsenic in equally small quantity, derived from rivers in the Lake District, had proved fatal to the charr. He presumed that arsenic exists in many other streams, the water of which is used with impunity, the arsenic being derived from arsenical pyrites, a very common mineral, by the action of air and water, and, as in the instanco of Whitbeck, comparatively harmless, and this owing to two circumstances—the very slight solubility of tho oxide in cold water, and the fact of the harmlessness of the oxide in infinitesimal quantities.

Some Observations on the Coagidation of the Blood in relation to its Cause. By John Daw, M.D., F.B.S., $c.

These observations were chiefly made to test the hypothesis brought foiward by Dr. Richardson, that the coagulation of tho blood mainly depends on the escape of ammonia. The many results described by the author were opposed to this view. First, he showed that blood in its healthiest state contains no appreciable quantity of the volatile alkali; and, secondly, that ammonia added to tho blood in a notable quantity did not arrest the change. Other experiments were described of a confirmatory kind.

The conclusion finally arrived at was that, we are still ignorant of the cause of the phenomenon, and that the hypothesis of Dr. Kichardson, if acted on in medical practice, must be attended with risk.

Remarks on the Loss of Muscular Power arising from the ordinary Footclothing now worn, and on the Means required to obviate this Loss. By James Dowie.

Iu wearing rigid-soled boots or shoes, tho waste of muscular power is of a threefold kind: first, that arising from atrophy, in which the locomotive function of the muscles of the extremities is reduced below its normal standard; second, that arising from the extra force exerted in bending comparatively rigid clothing; and third, that arising from the normal functions of tho muscles of the feet when walking being partially or wholly transferred to those of tho pelvic region or upper

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