case, all the nerves of the vessels, including those contributed by the sympathetic, are cut; in the second case, probably only a small number, which are from the first mingled with the trigeminus.

§ 98. The readiness with which inflammation may be excited by slight irritation in paralysed limbs, may be collated with the readiness with which reflex action occurs in the same limbs. As slight irritation calls forth by reflexion contraction of the muscles (sympathy), so a similarly slight irritation calls forth by reflexion relaxation of the vessels (antagonism.)

$99. The inflammation which sometimes accompanies spinal irritation, or neuralgia, Stilling explains in the same way as he does that which results from the section of the fifth pair for instance, he supposing that in neuralgia the sensitive nerves are in a state of paralysis. Henle maintains the opposite, and explains the inflammation on the principle of antagonism above mentioned, thus:-Neuralgia being a state of excitement of a sensitive nerve, determines antagonistic paralysis of the motor nerves of the vessels of the part, whence relaxation of their walls and dilatation of their caliber.

§ 100. In the preceding part of this Report, where the immediate cause of the stagnation of the blood in inflammation is under discussion, no reference is made to Stilling's views on the subject. Here it may be mentioned, that in addition to the set of cases above considered; viz., Ist, those occurring after section of the sympathetic; 2d, those occurring after section of sensitive nerves; and 3d, those accompanying spinal irritation; in which he says that there is paralysis of the nerves and relaxation and dilatation of the vessels; he admits another set of cases-traumatic -in which, on the contrary, there is constriction of the vessels in consequence of increased action of their motor nerves, determined from reflexion, from increased excitement of the sensitive nerves. He does not, however, attempt any detailed explanation of how the paralysis of the nerves and relaxation and dilatation of the vessels, in the one case, or the excitement of the nerves and constriction of the vessels, in the other, determine the stagnation. In the latter case, in particular, he makes no use of the alleged increased tone of the vessels in giving an explanation of the cause of the stagnation of the blood, but ascribes it to a morbid condition of the blood; thus, as Henle remarks, giving up his own principle, that the cause of inflammation operates through the nervous system, and calling into his aid a humoral pathological theory exactly in cases in which a change of the humours is least probable.

VII. EXUDATION.

§ 101. Immediately after or during the stagnation of the blood, exudation commences. From being at first serous the exuded fluid comes at last to be pure plasma, or at least a fluid containing a greater or less quantity of fibrin.

§ 102. The exudation may, in the aggregate, be attributed to the thinning of the walls of the vessels, from their relaxation and dilatation on the one hand, and the pressure from within the vessels on the other. Besides these, another condition suggests itself as likely to promote exudation, viz., the circumstance that the plasma will be pressed out from among the aggregating corpuscles, even when the blood would not, if out of the body, present the buffy coat, and that because within the body the fibrin of the plasma does not so readily coagulate.

§ 103. When, however, the mass of blood has already become changed to that condition in which the buffy coat would present itself were the blood drawn from the body, the plasma, at the same time that it is more quickly and energetically squeezed out from among the aggregating red corpuscles, will present itself in greater quantity and richer in fibrin, for transudation through the walls of the capillaries.

$104. The question, however, occurs, why does serum alone pass out first? The author of this Report thinks, with Dr. Watson, (Lectures on the Practice of Physic, vol. i, p. 155,) that it is, as in common oedema, owing to obstruction; the obstruction in inflammation being from the stagnation of the blood. But how obstruction determines exudation of serum alone, remains a question. To help

to a solution of this, it may be stated that, according to Kürschner, water passes most quickly through animal membranes, and saline solutions more quickly than viscid, gummy, and albuminous solutions.

§ 105. None of the corpuscles of the blood pass out along with the exuded fluid as long as the vessels are entire. But it is often observed that at certain points the walls of the vessels in which the blood was stagnated, have given way, and permitted an extravasation of both red and colourless corpuscles.

§ 106. With exudation is completed the inflammatory process, properly so called.

VIII. INFLAMMATION OF NON-VASCULAR PARTS.

§ 107. In certain non-vascular parts morbid actions may go on in all respects similar to those which usually attend or result from inflammation. The cornea for example, though it is vascular whilst being developed, is, in its fully formed and healthy state, non-vascular; and yet inflammation of the cornea is spoken of.

§ 108. The cornea, there is reason to believe, derives the materials necessary for its nutrition from the blood circulating in the vessels of the adjoining parts of the conjunctiva and sclerotica. Let it be inquired what takes place in the cornea when there is applied to it such an irritation as would excite inflammation in one of the vascular parts of the eye.

§ 109. When the cornea is injured then, congestion of the vessels, of the adjoining parts of the conjunctiva and sclerotica takes place, and exudation into the substance of the cornea by and by ensues. Thus, though non-vascular, and of course not the seat of inflammatory congestion, it becomes the seat of a very important part of the inflammatory process-the most important part, perhaps, as regards the events of the process.

$110. The cornea in this state may therefore be said to be, to all intents and purposes, inflamed-the only difference in respect to it, as compared with vascular parts, being that the vascular congestion is not in it, but in adjoining structures. § III. On the other hand, it is to be remarked, that although these adjoining structures are the seat of the congestion, little or no exudation may take place in them or on them, and they may therefore be said scarcely or not at all to be the seat of inflammation as regards the events of the process. When the conjunctiva and sclerotica are really inflamed, exudation in or on them may occur; but then the congestion is different in seat and extent from what it is in the former case, and there may be no exudation into the cornea-the cornea may remain unaffected.

§ 112. In the progress of inflammation of the cornea, this structure may become vascular, but such an event is owing to the development of new vessels, such as happens in inflammation of vascular parts, and as will be considered on another occasion.

§ 113. Though inflammation of the cornea considered as a non-vascular part, has been thus dwelt on, the truth is that all tissues as regards their component elements are properly speaking non-vascular, and differ from the cornea, only in degree of proximity to the vessels, and therefore in inflammation only in degree of the proximity to the source of the exudation.

§ 114. But this very difference presents a natural analysis of the inflammatory process. It enables one to observe separately, the two great stages of inflammation proper, the congestion and the exudation,-the congestion in one place, the exudation in another. It also enables one to observe, as will be shown on another occasion, in an uncomplicated manner, the eventual stages of inflammation, such as reorganization and suppuration. Lastly and especially, it enables one to analyse the mode in which the inflammatory irritation is communicated to the vessels, in other words, the mode of action of the exciting cause.

§ 115. In what is ordinarily called a vascular part, the irritation, for aught that could be said to the contrary, except by a round about process of reasoning as above seen, might act directly on the vessels as some maintain, but in the case of irritation applied to the cornea alone, and not either to the conjunctiva or sclerotica,

it cannot do so. And for the very simple reason that there are no vessels in it to be acted on. The vessels which are affected are those of the conjunctiva and sclerotica.

§ 116. The mode in which these vessels are affected in consequence of irritation applied to the cornea alone appears to be this: Excitement of the sensitive nerves of the cornea, (for the cornea has nerves, though no vessels, as at first shown by Schlemm, and since found by Valentin, Pappenheim, and others,) calls forth antagonistically, according to Henle's principle, a state of depression, a temporary paralysis of the motor nerves of the contractile fibres of the walls of the small arteries opening into the capillary network of the conjunctiva and sclerotica, adjoining the cornea. The consequence of this is first relaxation and dilatation of those arteries, and then accumulation and stagnation of blood in the capillaries in the manner already explained.

In the foregoing Report, no reference has been made to Mr. Travers's recent work on Inflammation, as it is principally occupied with the events of inflammation and the healing process. There is indeed nothing in it on the theory of inflammation proper, beyond the statement of the fact of stagnation of the blood in the vessels, and the effusion or exudation contingent on it.

BOOKS RECEIVED FOR REVIEW.

1. Du Traitement de la Phthisie pulmonaire. Par E. L. Pereyra, M.D.--Bourdeaux, 1843. 8vo, pp. 84.

2. Guide du Médecin Praticien, &c. Par F. L. J. Valleix, M.D., &c.- Paris, 1842-3. 3 vo's.

3. Handbuch der Allgemeinen Therapie, &c. Von Dr. Emil Kirchner.-Kiel, 1842. 8vo, pp. 373.

4. Das Medicinische Wien.

Von Wilhelm Herzig, M.D., &c.-Wien, 1844. 8vo, pp. 392.

5. Elements of Physiology. By Rudolph Wagner. Part III. On Sensation and Motion, completing the Special Physiology. Translated by R. Willis, M.D.-London, 1844. 10s.

6. Observations on the proximate causes of Insanity. By James Sheppard, Surgeon. London, 1844. 8vo, pp. 164.

7. The Influence of Climate and other agents on the Human Constitution, with reference to the Causes and Prevention of Diseases among Seamen. By R. Armstrong, M.D., Deputy Inspector of Hospitals and Fleets.-London, 1843. 8vo, pp. 207.

8. Parliamentary Report on the practice of Interment in Towns. By E. Chadwick, Barristerat-Law. London, 1843. 8vo, pp. 280.

9. Natural History, Pathology and Treatment of the Epidemic Fever at present prevailing in Edinburgh and other Towns. By J. R. Cormack, M.D.-London, 1843. 8vo, pp. 182. 5s. 6d.

10. The distinction between Instinct and Reason. An Introductory Lecture. By J. Strang, M.D.-London, 1843. 8vo, pp. 44.

11. An Introduction to Practical Organic Chemistry.-London, 1843 8vo, pp. 90.

12. On the Nature and Treatment of Tic Douloureux, Sciatica and other Neuralgic Disorders. By Henry Hunt, M.D.-London, 1844. 8vo, pp. 192. 6s.

13. Diseases of the Lungs from Mechanical Causes, &c. By G. Calvert Holland, M.D.London, 1844. 8vo, pp. 100. 4s. 6d.

14. A Letter to the Governors of the Brighton Dispensary, on the Constitution of Dispensaries for the relief of the sick poor. By a Medical Practitioner.-Brighton, 1843. 8vo, pp. 20. 15. Report of the Medical Infirmary Society. -Macao, 1843. 8vo, pp. 62.

16. Anatomical Manipulation; or the Methods of pursuing Practical Investigations in Comparative Anatomy and Physiology. By A. Tulk, and A. Henfrey.-London, 1844. 8vo, pp. 413.9s.

17. A Treatise on the tonic System of treating affections of the Stomach and Brain. By Henry Scarle, Surgeon. - London, 1843. 8vo, pp. 308. 6s.

18. The Medical Students' Guide and Almanac for 1844.-London, 1844. 8vo, pp. 180. 2s. 6d.

19. A complete condensed practical treatise on Ophthalmic Medicine. By E. O. Hocken, M.D. Part I.-London, 1844. Small 8vo, pp. 108.

20. Elements of Physiology, for the use of Students, and with particular reference to the wants of Practitioners. By Rudolph Wagner, M.D., and Translated from the German with Additions. By Robert Willis, M.D., &c.-London 1844. 8vo, pp. 700.

21. An Experimental and Critical Inquiry into the Nature and Treatment of Wounds of the Intestines. Illustrated by Engravings. By S. D. Gross, M.D., Professor of Surgery in the Louisville Medical Institute. Louisville, (United States,) 1843. 8vo, pp. 220.

22. Minor Surgery, or Hints on the every-day Duties of the Surgeon. By H. H. Smith, M.D Illustrated by Engravings.-Philadelphia, 1843. 12mo, pp. 303.

23. Practical Manual of the Diseases of the Heart and great Vessels. By J.A. Aran. Translated from the French by W. A. Harris, M.D.Philadelphia, 1843. Small 8vo, pp. 296.

24. On Regimen and Longevity. By John Bell, M.D.-Philadelphia, 1842. 8vo, pp. 420.

25. Two Essays on the Diseases of the Spine. By R. A. Stafford.--London. 1844. 8vo, pp. 92. 5s.