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not be made and published somewhere, but let them remain in our serial literature till a sufficient number are collected to throw light on each other and allow a complete treatise to be possible.

The subject of perfecting the materia medica being now before our body in a practical form, I hope that every one of us will make some sacrifice of time and trouble in contributing to that great work. It is much to be regretted that a want of unanimity has so often prevailed among even our small body, and hindered us putting forth our full strength for united work. Even now, since this project has become practical, our forces have been divided by the recent action of the British Homoeopathic Society, who have proposed devoting a certain portion of labour and money to an imperfect revision of the materia medica on the plan indicated by Aconitine in the October number of the British Journal of Homoeopathy. That plan can be of little or no use to the homoeopathic practitioner, and can at most do good by doing part of the work which has to be done in the complete materia medica of some future time, for the drugs selected first are not those which are to appear in the first volume alluded to throughout this paper. Would it not be better that the time and money thus spent should be devoted to the preparation of one or two more medicines for this volume?

THE ACTION OF DRUGS UPON THE EYE.
By Dr. Hughes.
Lecture II.

Resuming our study of the action of drugs upon the eye, we begin to-day with the most important member of the group,

Belladonna.

The deadly nightshade and its alkaloid atropia have, as you know, a wide and varied range of action upon the animal organism. When lecturing upon the drug as a whole, I have shown it to be a depressant of the functional energy of the motor and sensory nerves, while exciting the sympathetic; and also to act as an irritant upon several kinds of tissue, especially the muco-cutaneous and the (grey) nervous. It finds abundant scope for actions of this kind in the visual organs, and, as we shall see, it vigorously exerts them. Let us consider—first, its action upon the pupil; secondly, its inflammatory effects; and, thirdly, the disorder of vision produced by it.

I. The dilatation of the pupils, so regularly and uniformly caused by Belladonna and its alkaloid, whether applied locally or taken [internally, has long been a subject of great interest. The first question which arises is, Does this mydriasis depend upon the general influence of the drug upon the brain? I think such a position to be untenable, for the following reasons:

First, no fact is better ascertained about Belladonna than that it is an irritant to the intra-cranial nervous centres, exciting (while deranging) their functions, and causing them to attract a larger supply of blood than is natural. In a word, it sets up the first stage of inflammation therein. Now, this condition of the brain, when occurring idiopathically, is always accompanied by a contracted pupil; and it is not until the stage of exhaustion and effusion sets in that the pupils dilate. If, then, the enlarged pupil of Belladonna were a symptom of the state of the brain induced by it, that state should be precisely the opposite of what it really is.

Secondly, Sir E. Christison has put on record a case of poisoning by Opium and Belladonna conjointly, in which the cerebral symptoms were those of the former, while the pupils were "excessively dilated and not contractile." Here, as the venerable toxicologist observes, the Opium "prevented the delirium induced by Belladonna in the early stage; while, on the other hand, the Belladonna prevented the usual effect of Opium on the pupils, and actually produced the opposite action;" That is, the cerebral influence of the Belladonna was neutralised and superseded by that of the Opium; but its mydriatic power was fully exerted. If, now, the dilated pupil of Belladonna were symptomatic of the condition of the brain induced by the drug, we should have in this instance a contradiction of the axiomatic law, causd sublatd tollitur effectus.

Thirdly, it has been ascertained by experiment that the mydriatic action of Atropia, even when exerted through the constitution, is a peripheral one, and independent of the nervous centres. A full account of the observations which establish this view is given by Dr. H. C. Wood.* That it holds good when the drug is locally applied it is easy to believe; and it suffices to say that the effect may be produced after section of the trigeminus and the cervical sympathetic, and even after extirpation of the ciliary ganglion— in frogs after removal of the eye from the body. But Dr. Wood has observed a case in which, from a railway accident, the eye was (as proved by the autopsy) separated from all connection with the nerve-centres; and yet, when Atropia was given hypodermically, the pupil dilated.

We must conclude, then, that the dilatation of the pupil induced by Belladonna is the result of a local and peripheral action of the drug, and altogether independent of its effect on the central nervous system. An important practical inference follows from this conclusion, viz. that a dilated pupil is no necessary homoeopathic indication for the choice of Belladonna in cerebral disorder. It would, indeed, generally denote si condition of exhaustion or effusion, to which the drug is quite unsuitable. Mere phenomenal homoeopathy would demand its presence to make up the totality of symptoms; but here, as in so many places, physiology enables us to correct the impressions of our senses, and to obtain similia which shall be real and not apparent only. On the other hand, when Graves recommended the administration of Belladonna in the head affection of fever, when the pupils were contracted, although he thought himself acting upon the old principle of antipathy, his remedy was really homoeopathic to the morbid condition present. * Treatise on Therapeutics, 1st eel., p. 21&

I do not, of course, deny that a dilated pupil may be one of a group of symptoms to which Belladonna is homoeopathic and curative. It is a part of the general influence of the drug on the sympathetic (and perhaps musculo-motor) nervous system, though not of that which it exerts on the brain. Thus, Dr. Harley writes:—"The action of Belladonna in febrile diseases is frequently attended with results which are not only unexpected, but exactly the opposite of what is observed in health. Thus it may happen, if we give a dose of Atropia to a patient with a pulse of 120 or higher, a dry and hard tongue, and pupils measuring the g", that after ten, twenty, or thirty minutes, when the action of the Belladonna is fully developed, the pulse will be decreased, the tongue be moist, and the pupils contracted."*

We have yet to inquire by what means Belladonna exerts this local action which we have found it to possess. It has been shown that the pupil may be dilated either by depression of the influence of the third nerve, or by excitement of that of the sympathetic. The old conception of Belladonna as a "narcotic," and, later, the ascertained power of Atropia, locally applied, to paralyse the accommodatory action of the eye (of which more anon), has made it generally assumed that the mydriasis which occurs under its influence is due to paresis of the oculo-motorius, causing a relaxation of the circular fibres of the iris analogous to that of the sphincters of the rectum and bladder. There are, however, grave objections to this view, as a complete account of the phenomena, the most serious of which is that in complete paralysis of the third nerve (or after section of it in animals), the mydriasis is much less than that which results from Atropia, and may be considerably increased by the use of the drug. Dr. Harley, too, aptly points outf the difference between the effects of Conium (which undoubtedly paralyses the oculo-motorius) and those of Belladonna on the eye.

• Von Graefe has sometimes observed ephemeral mydriasis as a premonitory symptom of insanity, especially of ambitious monomania, t Old Vegetable Neurotics, p. 233.

This physician, with Wharton Jones,* Benjamin Bell,t Allen Thompson,! and (formerly) myself,§ have maintained that the mydriasis of Atropia is dependent entirely upon sympathetic excitation. That it does produce this effect generally is shown by the contraction of the arterioles which it induces; and that it exerts the same action upon the eyes is evident from the widely open, staring, and protruded appearance they present under its influence, this group of symptoms concurring with dilatation of the pupils when the sympathetic is galvanised in the neck. Vulpian, moreover, has observed that in poisoning by Woorara, as long as galvanisation of the cervical plexus occasions dilatation, however slight, of the pupil, so long Belladonna also will determine it. Again, it is evident that (as Dr. Wood justly states) the dilatation produced by the drug is "not merely a passive movement of relaxation, but is active, capable of tearing up inflammatory adhesions, even when of some firmness." I cannot doubt, therefore, that to excitation of the radiating fibres of the iris through the sympathetic the mydriasis of Belladonna is largely due. At the same time, as there is good evidence, from the failure of accommodatory power, that the ciliary branches of the third are paralysed under full atropism, relaxation of the circular fibres may also be a factor in the result.

Is the pupil ever contracted under the influence of Belladonna, and, if so, what explanation can be given of it? Such a symptom is noted by four of Hahnemann's provers, and by himself (S. 646-8-9 in Allen). Dr. Harley, too, has observed that just before the mydriasis of the drug has set in, the influence of light will cause the pupils to contract more closely than under similar circumstances before the ingestion of the drug. "This contraction has persisted for several minutes, when all at once the pupil has given way and become broadly dilated." Dr. Sharp, who finds that he can induce slight contraction of his own

* Ophthalmic Medicine and Surgery.
f Sdin. Med. Journal, July, 1858.
J Glasgow Med. Journ., Jan., 1857.
§ London Med. Seview, Aug., 1860.

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