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Universel de la France, Paris, 1804; Dictionnaire Géographique Universel, Paris, 1827; Waysse de Williers, Itinéraire Descriptif de la France, Paris, 1813; Malte Brun, Balbi, &c.) DROMEDARY. (CAMEL, vol. vi., p. 191] DRO'MIA (Fabricius), a genus of brachyurous decapod crustaceans, placed by M. Latreille in the section of Notopoda, and referred by Dr. Leach to the family of Thelariopoda. Generic character.—External antennae small, inserted below the ocular peduncles; the intermediate antennae placed below and a little within the eyes: external jaw-feet with their third joint nearly square, slightly notched at the extremity and within: claws (chelae) great and strong; feet of the second and third pair terminated by a simple joint, and larger than those of the fourth and fifth pair, which are elevated on the back and provided with a claw, inasmuch as the last joint, which is bent and pointed, is opposed to a spine nearly of the same form, which terminates the penultimate joint: carapace oval, rounded, very convex, cut (découpée) on its anterior borders, hairy or rough (hérissée) as well as the feet and chelae: eyes small, supported on short peduncles, rather'approximated, and lodged in orbicular or cylindrical fossae. (Desmarest.) Geographical Distribution.—Probably extensive in the seas of warm climates. The Mediterranean, the Cape of Good Hope, and the Antilles, are given as localities. Habits, &c.—The Dromiae are indolent in their motions, and live in spots where the sea is moderately deep, choosing for their habitation places where the rocks are not hidden under the sand. They are almost always found covered with a species of Alcyonium or with valves of conchifers, which they retain with their four hinder feet, and which seems to serve them as a shield against their enemies. The Alcyonia, which are in general of the species named Alcyomium Domuncula, continue even to develop and extend themselves upon their carapace, which they at last entirely conceal. In the month of July, according to M. Risso, the females come out of the state of torpor (engourdissement) in which they ordinarily are, and betake themselves to the shallows for the purpose of depositing there a great number of eggs. (Desmarest.) Place in the series.—Dynomene, according to Desmarest, should be placed next to Dromia, the former differing from the latter principally in having the feet of the fifth pair only instead of the four last, elevated on the back. In general the Dromiae bear a great resemblance to the Crabs, properly so called, in the general form of the body, the structure of the parts of the mouth, the position of the antennae, &c.; but they differ from them in the elevated situation of their four posterior feet and in their manners. Example, Dromia hirsutissima. Carapace very convex, with six dentations on its lateral borders, and with a large sinus of each side of the front, which is nearly trilobated. #. covered with long red hairs. Locality, Cape of Good ope.
DROMORE, a bishop's see in the ecclesiastical province of Armagh in Ireland. The chapter, which is o ated by patent of James I., consists of dean, precentor, chancellor, treasurer, archdeacon, and one E. This diocese occupies the western portion of the county of Down, and extends partially into Armagh and Antrim. The greatest length from north to south is 35% English miles; and the greatest breadth, from east to west, 21% miles. It contains 26 parishes, constituting 25 benefices. . In 1792 there were 27 churches of the establishment in this diocese: in 1834 the numbers were, churches of the establishment 27; Roman Catholic churches, 34; Presbyterian churches, 45; other houses of Protestant worship, 24. In the same year the gross population of this diocese was 188,209, of Wi. there were 41,737 members of the Established Church; 76,275 Roman Catholics, 69,264 Presbyterians, and 933 other Protestant dissenters. There were at the same time in this diocese 233 schools, educating 16,987 young persons, being in the proportion of 9th per cent. of the entire population under daily instruction, in which respect Dromore stands twelfth among the 32 dioceses of Ireland. Of the above schools 23 were in 1834 in connection with the National Board of Education.
The foundation of this see is attributed to St. Colman in the 6th century. Its early history is obscure, and there is no regular succession of bishops on record till after the 12th century. Dr. Jeremy Taylor, who had the administration of this diocese granted him in addition to that of Down and Connor by King Charles II. in 1661, and Dr. Percy, the learned collector of antient English ballad poetry, have been the most distinguished bishops of Dromore. The bishop's house, which is a plain mansion, was built by Doctor Beresford in 1792. Before his time the episcopal residence had been at Magheralin. By act 3rd and 4th Wm. IV. c. 37, this bishopric when void becomes incorporated with the united diocese of Down and Connor, and its revenues vest in the board of Ecclesiastical Commissioners.
DROMORE, a pretty well built town and thriving linen market, in the barony of Lower Iveagh and County of Down, is situated on the Lagan, 66 Irish or 84 English miles from Dublin on the great northern road to Belfast. The cathedral is a mean structure on the bank of the river. East of Dromore stands a remarkable mound, 60 feet high, with three concentric entrenchments, and an extensive outwork towards the Lagan. The population of Dromore in 1831 was 1942. (Beaufort's Memoir of a Map of Ireland; Harris's Ware's Works; Reports, &c.) [Down.]
DROPSY, HYDROPS, a preternatural collection of watery fluid in different parts of the body. In the state of health, there is constantly poured out upon every surface, cavity, and interstice of the body, a watery fluid derived from the blood and deposited by o capillary blood-vessels. [CAPILLARIEs.] This fluid does not remain long where it is deposited, but by vessels appropriated to the office, termed absorbents, is soon taken up and reconveyed into the common circulating mass. As long as there is a perfect balance of action between these two sets of vessels, which is always the case in health, there is no accumulation of fluid, the exhalation and the absorption being always exactly equal. But if from any cause that balance be disturbed; if either the capillary blood-vessels pour out an unusual quantity of fluid, or if the absorbents A. to act with their accustomed energy, an accumulation of fluid must necessarily take place, and this accumulation, when it amounts to an appreciable quantity, constitutes the disease called dropsy. o follows that dropsy must always be the consequence either of increased exhalation or of diminished absorption.
The causes which lead to increased effusion are exceedingly various; but they are all resolvable either into those which produce a morbid condition of the blood-vessels, an obstruction to the free circulation of the blood, or a morbid condition of the blood itself. The morbid condition of the blood-vessels may be of two opposite kinds, either that of preternatural strength, in consequence of which their action may be so excited as to pour out an unusual quantity of fluid ; or that of extreme debility, in consequence of which they may be unable to prevent a preternatural exudation of the thinner parts of the blood through their relaxed coats. These different states of the blood-vessels depend on two diametrically opposite conditions of the system, and accord
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ingly the different species of dropsy are very generally divided into active or passive, acute or chronic, sthenic or asthenic. Whenever an obstacle is opposed to the free return of the blood from the capillary arteries into the capillary veins, the blood accumulates in the capillary arteries, which are the exhalent vessels. By this accumulation of blood in the exhalents, either their action is increased, the consequence of which is increased exhalation; or their action is diminished and their tone destroyed, the consequence of which is equally increased exhalation. Various morbid conditions of many organs oppose a free return of the circulating blood from the capillary arteries into the capillary veins: any disease of the right side of the heart, for example, which prevents its receiving from the great venous trunks of the body the quantity of blood in a given time, which is necessary to maintain the balance of the circulation; any disease of the lungs, which prevents the lungs from receiving from the right ventricle of the heart the full quantity of blood which the heart has received from the great venous trunks; any disease of the liver, which prevents the liver from receiving by the great vein which ramifies through it the vena portae, the full quantity of blood which it ought to receive from the different abdominal viscera; any disease of the great blood-vessels themselves, by which the current of the circulating blood is prevented from passing freely through them. Such a disease of the heart may be occasioned by an ossification of its valves; of the lungs, by an obliteration or compression of its air vesicles, upon the walls of which the capillary terminations of the pulmonary artery are distributed; of the liver, by an induration of its substance and a consequent mechanical compression of the minute branches of the vena porta ; of the great bloodvessels, by diseases of their coats giving rise to the tumours called aneurisms, or by the compression of tumours existing in neighbouring parts, scirrhous, fatty, or watery tumours, which may have their seat in any organ, or by the compression of the great venous trunks of the system by the bulk of the distended uterus in pregnant women. When dropsy is the result of an increased action of the capillary blood-vessels, it is considered a primary or idiopathic disease, and constitutes the sthenic, tonic, active, or acute dropsy of authors. In this case the capillaries are conceived to be in that state, whatever it may be, which constitutes acute inflammation. The increased effusion, which constitutes the dropsy, is the result of that increased action, and by the effusion the inflamed state of the vessels is often removed. This form of dropsy occurs most frequently in the young, the plethoric, and the robust. It is induced by all the causes of inflammation, such as cold, suddenly checked perspira‘ion, suppression of any of the natural secretions and discharges, a plethoric condition of the system, a repulsion of acute diseases of the skin, &c. It has its seat most frequently in the serous membranes of the great cavities of the body, the walls of which are lined by those membranes, as those of the chest and abdomen, or of the viscera to which these membranes afford an external covering, as the brain, the lungs, the heart, the liver, and all the abdominal and pelvic viscera. This form of dropsy is attended with a greater or less degree of fever, the invariable concomitant of acute inflammation. . The febrile symptoms are general uneasiness, more or less restlessness, pains in the back and limbs, heat of skin, preceded by chilliness, headache, suppression of the secretions and excretions, and consequently a dry or clammy state of the mouth, a constipated state of the bowels, and a loss of appetite. The pulse is always excited, and is usually full and hard, or small and sharp. There is commonly some degree of pain in the organ in which the inflammation has its principal seat. When the inflammation and febrile symptoms are intense, the pain is usually acute and its seat clearly defined; but when the inflammation and febrile symptoms are not very intense, the pain may be slight and its seat correspondingly obscure; but some degree of pain or uneasiness may generally be found is carefully sought for, and at all events the true seat of the inflammation may be usually detected by the disordered function of the affected organ. When this condition of the system exists with a certain degree of intensity it constitutes the most acute form of dropsy ; but when it exists with less intensity it gives rise to another form of the disease, termed sub-acute dropsy, in
which the symptoms are the same but less urgent. In this case there is often little or no local pain; the febrile symptoms are milder, the general uneasiness is less prominent, the skin less hot; there may be little or no thirst, and the pulse much less hard and sharp. This form of the disease is equally dangerous in itself, and often more fatal, in consequence of its true nature being overlooked, until it has made such progress that its course is no longer to be checked. It is often the consequence of more acute diseases, and frequently follows scarlet fever, measles, bronchitis, inflammation of the pleura, inflammation of the liver, influenza, &c. The original and urgent disease may subside, and then comes on slowly and almost imperceptibly this insidious and fatal malady. The third form of dropsy is that termed asthenic, or passive. It is so generally the consequence of some othel morbid condition of the system that it is not usually considered a primary or idiopathic disease, but merely a sequent or ultimate result of some other pathological state Its proximate cause is conceived to consist partly of a laxity of the tissues of the exhalant vessels, in consequence of which they are incapable of retaining the fluid part of the blood; and partly of an altered condition of the blood itself, in which its solid portions, namely, its albumen, fibrin, and red particles [Blood] are preternaturally diminished and its serum proportionally increased. The state of the system in which this form of dropsy usually comes on, and the causes which most frequently and obviously induce it, are supposed to conduce equally to this morbid state of the containing vessels and the contained blood. The state of the system in which it comes on is that of extreme debility, however induced ; but its ordinary exciting causes have so obvious and great a tendency to exhaust the vital power, that they are usually denominated debilitating causes; such are fever, whether intermittent or continued, exanthematous or typhus, long continued and excessive evacuations, whether of natural discharges, or of preternatural effusions of blood, deficient or unwholesome die!, diseases of the digestive organs, by which the due assimilation of the food is prevented, intemperance in the use of intoxicating liquors, whence drunkards of all kinds, and especially dram-drinkers, so commonly, nay, almost invariably, die of dropsy. The acute and inflammatory forms of dropsy ordinarily produce increased exhalation only into paricular parts of the body; but this state of general debility may give rise to an increased exhalation into every cavity and interstice, and thus bring on a general dropsy. Thus it is by no means uncommon to have at one and the same time effusions into the cavity of the cranium, into that of the thorax, into that of the abdomen, and likewise into the cellular tissue almost over the whole body. In such cases the operation of a general cause is rendered manifest by these several dropsies increasing in one part as they diminish in another, and this alternately in the different parts. This combination of the different species of dropsy, or rather, as it may be justly termed, this universal dropsy, must, it is argued, be referred to a general cause, and in most instances, hardly any other can be thought of but a general laxity of the exhalants. It is this which constitutes what is called the hydropic diathesis, which frequently occurs by itself, and frequently concurring with other causes, is especially that which gives them their full effect. This state of the system, when it first comes on, gives rise to a disordered, enfeebled, and wasted appearance of the body, which is commonly called a breaking up of the constitution, and is technically termed a cachexy; in a very short space of time it is usually followed by general dropsy. All the acute inflammatory and febrile symptoms so characteristic of the other forms of dropsy are of course absent in this. The skin, instead of being hot, is often unusually cold; the pulse, instead of being full and hard, is weak, small, unequal, and rapid ; the contraction of the heart is so feeble that slight causes often completely arrest its action, and render it incapable of carrying on the circulation, whence the patient drops down dead instantaneously. perhaps on endeavouring to walk down stairs, or to move from one chair to another; the muscles in general are flaccid, all the movements are weak, irregular, and uncertain, and all the actions of the system exceedingly feeble. It is more especially this last form of dropsy which is induced by a morbid change in the constitution of the blood, namely, an increase in the proportion of its serum. An
unusual quantity of water taken into the body, and not carried off by the excretory organs, may possibly give rise to such a condition of the blood, and accordingly it is said that suddenly drinking large draughts of very cold water has been immediately followed by dropsy, probably from the cold producing a constriction of the excretories; in consequence of which they are unable to carry off the water as it flows into the mass of blood and thus to maintain its proper constitution. A preternatural abundance of the more, fluid parts of the blood may also accumulate in the circulating mass by a suppression or diminution of the ordinary aqueous excretions. ence the influence of a cold and moist atmosphere in inducing dropsy; and the highly important influence of diseases of the kidneys in producing the disease. It is found that there are several different diseases of the kidneys of which dropsy is the ordinary result. . It is the office of the kidney to remove from the blood a large proportion of its fluid parts; it is an excreting and depurating organ of the greatest importance. Any disorder of it which interferes with the performance of its function may therefore occasion an accumulation of the watery particles of the blood, and thus give rise to dropsy; and it is . found that when the secretion of the urine is suppressed, the watery portion of the blood is often poured into some of the internal cavities. Moreover, large abstraetions of blood are frequently followed by dropsy, because the albumen, the fibrin, and the red particles which constitute the solid parts of the blood are not so easily renewed as the serum, and the superabundant serum readily passes off by the exhalants preternaturally relaxed by the debilitated state of the system induced by the bleeding. The parts of the body in which the dropsical effusions usually collect are the cavities of the cranium, chest and abdomen, and the interstices of the cellular tissue diffused over the whole body, and forming a constituent element of every organ. The dropsical fluid itself consists for the most part of the serum of the blood; but its sensible properties and its ohemical constitution vary exceedingly according to the form of the disease and the condition o the capillary vessels at the moment the effusion takes place. If the vascular action have been great, the fluid is yellow or straw coloured like whey, and is more or less turbid, and contains minute particles of albumen and fibrin. If, instead of excited vascular action, the effusion have been the consequence of an altered condition of the blood, the fluid is darkcoloured and turbid, probably from the admixture of the red particles of the blood. If the effusion have taken place very slowly in consequence of the operation of some cause progressively but not rapidly impeding the circulation more and more, the fluid is almost colourless and nearly destitute of animal matter. If the fluid have been long retained in the cavity containing it, it may be of all colours and consistence, and its sensible properties may be infinitely diversified, and these diversities are apparently increased by the admission of the external air to the cavity in consequence of the artificial removal of the fluid by the operation called tapping. But another general cause of o has been stated to be, interruption or diminution of the absorption which should take up the exhaled fluids from the several cavities and interstices of the body. It is obvious that absorption may be diminished, or may cease altogether, from a loss of tone in the proper absorbent vessels. Without doubt, a certain degree of tone or power is necessary in the absorbent extremities to enable them to perform their office; and it was justly observed by Cullen, that the same general debility which produces that laxity of the exhalant vessels which constitutes the hydropic diathesis, occasions at the same time a loss of tone in the absorbents; that therefore a laxity of the exhalants generally accompanies a loss of tone in the absorbents; that consequently a diminution of absorption must have a considerable share in the production of dropsy; and that this is rendered the more probable since dropsies are often cured by medicines which seem to operate by exciting the action of the absorbents. There are many diseases of which dropsy is the sequent, and the dropsy induced in this indirect mode is called secondary, consecutive, symptomatic, or passive, in contradistinction to its primary acute and active forms. The diseases which precede dropsy as their ordinary consequent have their principal seat in the heart, and its great vessels, in
and the ovaria. When dropsy is the consequence of disease of the heart, the signs of disease of the heart commonly long recede the appearance of the dropsy. The diseases of the #. which most commonly give rise to dropsy are passive dilatation of its muscular parietes and ossification of its valves, the existence of which may be ascertained with tolerable certainty both by certain signs which are pathognomonic of these organic changes, and by auscultation. When dropsy is the consequence of disease of the heart, the effusion is commonly indicated first by swelling of the face, especially beneath the eyelids, and next by swelling of the feet and ankles, and of the hands and arms, particularly of the left. As in the progress of the disease the effusion collects and accumulates in the cavity of the thorax, or in that of the pericardium, it is denoted }; peculiar train of symptoms hereafter to be described. [HYDROTHoRAx and HYDRops PERICARDII.] The respiration is always more or less embarrassed; the horizontal position uneasy, and often impossible; the pulse, which is seldom or never natural, is very variously affected. Whenever there is a watery swelling of the face, hands, arms, or ankles, with an impaired state of the constitution, the consequence of protracted ill health, and without manifest disease of the lungs, it may be certainly inferred that there is a disease of the heart. The dropsy which results from disease of the heart is very often completely removed by appropriate remedies. The effusion often recurs indeed, and is again removed, and this successive recurrence and removal of the affection takes place indefinitely until the cardiac disease, on which the effusion depends, reaches a point which is no longer compatible with life. Diseases of the coats of the great blood-vessels constituting aneurism, concretions within their cavities, or tumors of neighbouring parts, pressing upon their trunks, and obstructing the passage of the blood through their canal, are frequent causes of consecutive dropsy. Inflammation of the pleura o; the cavities of the chest, inflammation and congestion of the lungs, the consolidation or hepatization of the substance of the lungs, and the obliteration of the air-vesicles by the deposition of tuberculous matter, may give rise to effusion either into the cavity of the chest, or into the cellular tissue forming the parenchyma of the lungs, or into the cellular tissue diffused over the whole body. Inflammation of the liver, generally of a slow or chronic nature, leading to a deposition of adventitious matter in its substance, and the consequent enlargement of the organ and the consolidation of its tissue, is a common cause of dropsy, occasioned by the obstruction to the circulation through the vena portae, the effusion being in this case often confined to the cavity of the abdomen. The spleen, which consists of a congeries of blood-vessels, and which is very apt to be enlarged and obstructed, may occasion effusion into the abdomen in the same manner as disease of the liver. ... The kidneys are subject both to functional and organic "diseases, which are followed by effusions into all the cavities, in consequence of the failure of these organs to remove from the common mass of blood the superfluous and noxious principles which it is their office to eliminate. Dropsical effusions are often poured into the uterus and ovaria, in consequence of primary disease in these organs; at other times tumors are formed within or attached to them, which press upon and compress the trunks of neighbouring blood-vessels, and thus occasion dropsy by a me. chanical obstruction to the circulation of the blood. It is an interesting and important fact, that while in this disease the thinner parts of the blood are thus poured out into the several cavities and interstices of the body, the kidneys often remove to a very large extent the more solid portions of the blood, more especially the albumen, and sometimes even the red particles. , Hence there are several forms of dropsy in which the urine is loaded with a preternatural quantity of albumen, the presence of which may be detected by the application of heat, nitric or muriatic acids, alcohol, or corrosive sublimate, to the urine, all of which coagulate the albumen and thus render it visible. But albumen is not always contained in the urine of dropsical patients. It is of some importance in practice to discriminate the cases with albuminous urine from those without it, since there are remedies of great efficacy in the latter form of the disease,
the lungs, the liver, the spleen, the kidneys, the uterus,
which are useless, if not injurious, in the former. This fact
would indicate that dropsy with albuminous urine has its seat in a particular set of organs, and is dependent on a peculiar morbid action of those organs; and although very much still remains to be ascertained in relation to these points, yet some progress has been made at least towards determining the seat of the malady, if not the nature of the affection when the urine is albuminous. The condition of the urine in this respect ought therefore always to be examined, because it may throw some light however small on the constitutional and local disorder, and may be some guide to the judgment in the selection of remedies. Dropsy is always a formidable and often a highly dangerous disease. Its acute forms, though attended with the most urgent symptoms, are in general less unfavourable than most of its chronic forms, because in the former, though the disordered actions may be very intense and dangerous, yet they are more under the controul of remedial agents, and they often do not depend on any irreparable vice of the constitution, whereas the latter are the sign and the result of deep-seated and surely advancing disease. Of course the prognosis in any particular case must entirely depend on the seat and nature of the disease of which it is the sequent. There is no disease which requires a more varied treatment than dropsy, because, like fever, dropsy may exist in, and be essentially connected with, diametrically opposite morbid conditions of the system. Dropsy may depend on a state of the system, for the removal of which all other remedies will be tried in vain unless their application be preceded by a decided abstraction of blood: dropsy may depend on a state of the system in which the abstraction of the smallest quantity of blood may prove almost instantaneously fatal: in the former case stimulants and excitants invariably increase the intensity of the disease; in the latter they are indispensable to the preservation of life. On the clear discrimination of these two different states of the system, and the two different classes of disease to which they give rise, and on the sagacious detection of the different shades b which they may appear to be blended with and lost in eac other, the successful treatment of dropsy mainly depends. In the acute form of dropsy dependent on active inflammation, blood-letting is necessary, just, as it is in ordinary inflammation, the quantity of blood which it is proper to abstract depending, of course, on the organ inflamed, on the intensity of the inflammation, and on the strength of the constitution. One full bleeding will commonly suffice; but there are many cases in which its repetition is indispensable. In the great majority of cases, however, after a full bleeding from the arm, the local will be preferable to a repetition of the general bleeding: The next indication after blood-letting is to equalize the circulation and to promote the secretions. This is most effectually accomplished by bringing the system under the influence of mercury, by calomel combined with James's Powder or with opium, and this treatment may be conjoined with diuretics, of which digitalis is the best. In the subacute form the same general plan of treatment is necessary, but it can by no means be carried to the same extent, and in each individual case the application of the remedies employed must of course be modified according to the circumstances peculiar to that case. In the chronic, passive, or asthenic form, life would be destroyed by the employment of the remedies which alone are efficacious in the acute form. In this debilitated state of the system the abstraction of the smallest quantity of blood is highly pernicious. The safer and the most efficient remedies in this form of the disease are tonics, the laxatives called deobstruents, taraxacum, mild unirritating doses of mercury, and iodine, particularly in the form of the hydriodate of potass. The only effectual treatment of consecutive dropsy is that which is proper to the removal of the primary disease. But the detection of the true seat and nature of those organic diseases which are antecedent to dropsy is often a matter of extreme difficulty, requiring patient and acute investigation, and an extensive and precise acquaintance with pathology. And the treatment of the disease when ascertained, the selection of the appropriate remedies, and the employment of these with due, and only with due, activity and vigour, is a delicate and difficult task, sometimes rewarded, when performed with sagacity and skill, with a degree of success not to have been anticipated. It is pre-eminently in cases like these that the scientific and discerning phy
sician saves, when the ignorant, careless, and routine practitioner destroys. [HYDRocKPHALUs, HYDROPs PERscaRDII, HYDROTHoRAx, &c.]
DROPWORT, a poisonous wild umbelliferous plant, with fleshy-fingered roots, inhabiting ditches and wet places. It has been sometimes sold fraudulently by itinerant gardeners as a new species of dahlia. Its botanical name is OEnanthe crocata.
DROSERA'CEAE, a natural order of albuminous exogenous plants, consisting of marsh herbs, whose leaves are usually covered with glands or glandular hairs, and whose flowers are arranged in circinate racemes. The calyx consists of five sepals: there are five petals, five or ten hypogynous stamens, a one-celled many-seeded capsular fruit, and minute seeds, having an embryo lying at the base of a large quantity of albumen. There are many species of the genus drosera, called in English sundews, more remarkable for the singular structure of their glandular hairiness than for the beauty of their flowers, and of no known use. few other little-known genera are associated with it; and it is probable that dionaba [Dion*:A], whose singular irritable leaves have much analogy with those of drosera, also forms a part of the order, notwithstanding its indehiscent fruit and erect vernation.
De Candolle having inexactly described the embryo as lying in the axis of the albumen, the true affinities of the order were overlooked; they have lately however been more correctly determined to be with Cephalotaceae and Francoaceae rather than with Violaceae, §. or Frankeniaceae.
A plant of Drosera rotundifolia. capsule magnified—the seeds are seen between the valves of the capsule; 3, a seed very much magnified—the dark space in the middle is the nucleus, the remainder is a loose integument that invests the seed; 4, a section of the nucleus still more magnified—bere the minute dicotyledonous embryo is seen at the base of the albumen. & toen
DROWNING, the state of asphyxia [Asphyxi duced by the immersion of the body under water. a warm-blooded animal is immersed under water, and forcibly retained there, he immediately begins to struggle violently, and uses every effort to rise to the surface. These struggles are not at first the result of pain, but of fear. It is proved by direct experiment that the obstruction to the respiration which produces pain does not come on for some time. The point of time when the painful impediment to respiration occurs is well o For the reason assigned in the article Asphyxia, in the space of three quarters of a minute a violent effort is. made to inspire, to expand the lungs with air, but no air con enter. Every
l, a complete flower magnified; 2, a ripe
effort to inspire is followed by a corresponding effort to expire. At each expiration a small quantity of air is expelled from the lungs, and is seen under the surface of the water in the form of bubbles; for although the water excludes the air from entering the lungs, notwithstanding the most violent efforts to inspire, yet it cannot prevent some portion of air from being expelled from the lungs by the violent efforts to expire. The ultimate result of these repeated and violent expirations is greatly to diminish the bulk of the lungs, and to bring them to the utmost degree of collapse to which it is possible to reduce them by any voluntary or instinctive efforts which the animal is capable of making. When a human being is drowned by accident, if the fall has been from a considerable height and the water is not of very great depth, the body is precipitated to the bottom of the water; it then quickly rises to the surface, partly because the specific gravity of the body, when the lungs are full of air, is less than that of water, and partly because the body is rendered still lighter by the air, always amounting to a considerable quantity, which is collected and retained in the clothes. If the person be not able to swim, he generally struggles violently, and probably screams; by these efforts the lungs are partly emptied of the air they contained, the comparative weight of the body is increased, and consequently it again sinks to the bottom, but it soon again rises, and this alternate rising and sinking may occur several times in succession. Whenever the body comes to the surface and the mouth is above water, the painful impediment to respiration produces an instinctive effort to inspire, and a hurried gasp is made to obtain air. But ofen the mouth is not sufficiently above the surface of the water to obtain air without respiring a quantity of water along with it; but the quantity of water received in this manner is never great, probably not more than is expelled by the cough excited by the irritation of the glottis in consequence of the contact of the water and by the subsequent expiration. Every instant the body remains in the water, for the reasons immediately to be . the powers of sensation and of voluntary motion rapidly diminish, and at length, perfectly insensible and motionless, it remains at the bottom of the water, where, if wholly undisturbed, it continues until the disengagement of various gases in the progress of putrefaction renders it again specifically lighter than water, and brings it once more to the surface. The change in the system produced by continued submersion, the consequent suspension of respiration, and the necessary extinction of life, are all referrible to one pathological condition, namely, a change in the nature of the blood. The water prevents any portion of air from entering by the trachea to the air vesicles of the lungs; consequently no air comes in contact with the venous blood contained in the capillary branches of the pulmonary artery which are spread out upon the walls of these air vesicles; the venous blood which flows to the lungs is therefore incapable of being converted into arterial blood, whence the lungs can deliver to the left side of the heart only venous blood to be sent out to the system. As the circulation goes on, all the arterial blood in the body is at length converted into venous, and flows into the great venous trunks of the system, by which it is returned to the right side of the heart, and thence to the lungs, where it undergoes no change, but remains venous. These currents of venous blood, and of venous blood only, are successively sent out to the system. But venous blood is incapable of maintaining the action and vitality of the brain and spinal cord of the heart, of the voluntary muscles, or of any organ of the body, and consequently, when nothing but venous blood circulates in the system, the death of all the organs is the sure and quick result, and the organs die in the order and mode already described. [Asphyxia.] Taking the average of a great number of experiments, it is found that when an animal is forcibly and continuously held under water, the blood in the arteries loses its vermiion colour, and begins to grow venous in the space of three quarters of a minute. In one minute and a quarter it is obviously dark. In one minute and a half, no difference can be distinguished between the blood in the arteries and the blood in the veins; consequently, in an animal that is submersed and that never rises to the surface, the system is brought completely under the influence of venous blood in the space of one minute and a half, and though the body should remain under water half an hour, the blood does
not become sensibly darker, because it can only be completely venous. Circumstances may make a few seconds difference in regard to the point of time when these phenomena take place. If for example an animal be submersed at the instant of expiration, the colour of the blood is lost somewhat sooner than when it is submersed at the instant of inspiration, and if the animal be much alarmed and struggle violently, the change takes place with greater rapidity; but the difference from any cause of this kind never amounts to more than a few seconds. Age however is capable of effecting a more remarkable difference. It is proved by numerous and accurate experiments that the younger the animal the longer it can live when deprived of air by submersion. If, as is commonly the case, an adult warm-blooded animal be irrecoverably dead in the space of four minutes after complete and continuous submersion, an animal of the same species only a few days old will live twelve minutes. A pup will live considerably longer than a young dog, a young longer than a middle aged dog, and a middle aged longer than an old dog. Sensibility and the power of voluntary motion are diminished the moment the arterial blood begins to lose its vermilion colour; an animal is completely insensible, and has wholly lost all power of voluntary motion, that is, it is in a state of apparent death, as soon as the arterial blood is completely venous. In one minute and a half, then, after complete and continuous submersion, animal life is completely extinguished. But by the prompt and vigorous use of the appropriate remedies, recovery from this state is possible; because the organic functions go on for a considerable period after apparent death, and death is not real until the organic functions have wholly ceased. Neverthe less, though the organic functions may continue for an indefinite period after the animal functions are extinguished, from ten minutes to half an hour, or more, yet, in no instance in which the experiment has been fairly tried has any adult warm-blood animal that has been completely and continuously submersed for the space of four minutes been capable of resuscitation, though all the means of restoring animation may have been instantaneously and most actively and judiciously employed. Accordingly it is found in practice that the immediate and vigorous use of the best means for restoring animation often fail when the person has not been in the water more than four minutes. In general, however, if the body has not been in the water longer than from five to eight minutes, the prompt and persevering use of the proper means for restoring animation will succeed; no doubt, because in some one of or in all the times that the body has come to the surface air has been obtained and conveyed to the lungs in the hurried gasp instinctively made at these moments. Still it is exceedingly rare that persons are recovered who have been in the water fifteen minutes; occasionally however animation is restored after a submersion of twenty minutes, or even half an hour; and apparently authenticated cases are on record in which resuscitation was accomplished after the body had been in the water for three-fourths of an hour. In these cases, circumstances must have favoured the occasional inspiration of air; it is utterly impossible that life can have been maintained so long unless the individual had breathed at intervals during the time; and as none can tell what circumstances may have occurred favourable to the inspiration of air, it is an imperative duty in all cases to resort to the proper means for restoring animation with all the promptitude and energy possible. When a person who has been drowned, who was previously in a state of sound health, is taken out of the water, the appearances presented by the body are the following:— The whole of the external surface is cold: the colour of the skin is pallid, excepting in the parts where it is livid rather than pallid, as in the face, which is always either entirely pale or slightly livid. The eyes are half open, and the pupils much dilated. The mouth and the nostrils contain a great deal of frothy fluid. A large quantity of the same kind of fluid is contained in the trachea, the bronchial tubes, and the air vesicles of the lungs. The tongue is protruded between the teeth, and approaches to the under edge of the lips. The whole head is sometimes much swollen, and the features occasionally present the appearance of those of a person who has died from apoplexy; and this is said to be particularly the case with those who have fallen