809 



HYPOXANTHIN. 



HYSTERIA. 



810 



must be to the exclusion of the other ; but if both may be true, then 

 the phenomenon z may possibly be partly due to one and partly to 

 the other. 



An hypothesis thus assumed is obviously no more than a probable 

 truth; and the existence of sects embracing different hypotheses is 

 thus rendered not only natural, but even desirable. The consequence 

 of such division is, an ardour of investigation which would not other- 

 wise be felt, in order to find out experiments or to make deductions 

 decisive of the points in dispute. The rivalry between the emanatory 

 and undulatory hypotheses on the nature of light has much increased 

 our knowledge of that agent. But if at the same time it should seem 

 that the idea which a reader entertains of physical science must be 

 lowered by hi learning to take such a view of a hypothetical founda- 

 tion as that which has here been given, it should also be remembered 

 that the exactness of natural philosophy does nothing but expose the 

 uncertainty of human knowledge in general, at the same time that it 

 reads a lesson to the cultivators of other branches of learning. The 

 hypothesis of attraction, for instance, though established on much 

 stronger grounds of probability than conclusions in connexion with 

 which the word hypothesis is never mentioned, is remembered as being 

 only an hypothesis. 



At the same time the word hypothesis, like that of theory, has been 

 frequently applied in a disparaging sense to speculations in which 

 suppositions have been made for the purpose of drawing conclusions, 

 and not, as in physics, with the view of supplying probable antecedents 

 to conclusions which are already drawn from experiment. A notion is 

 to be supported ; it would be too obvious a fallacy to make the mere 

 assertion of it an argument in its own favour, and thus some antece- 

 dent proposition, from which the one in question will follow, is 

 assumed or attempted to be proved. To prove D, assume A, taking 

 care that it shall be easy to show that from A follows u, from B 

 follows c, and from c follows D. This is a use of hypothesis the direct 

 converse of that which is made in physics, where D is supposed to be 

 known and admitted, and it is asked which among all the A'S from 

 which it might follow is that from which it most probably does 

 follow. [CAL-SE.] 



HYPOXANTHIN (C 10 H.N 4 4 ). A peculiar substance met with in 

 the fluid of the human spleen, and also in that of the ox. It has also 

 been found in the fluid pressed from the muscle* of the heart, and in 

 small quantity in the blood of oxen. It presents the appearance of a 

 white crystalline powder, which is almost insoluble in cold hydrochloric 

 acid. One part of hypoxanthin requires 1090 parts of cold, or 180 

 parts of boiling, water for its solution. It is very slightly soluble in 

 boiling alcohol. Its solution in water possesses a neutral reaction. 



HYPSOMETRY. The process by which heights are measured by 

 the indications of the barometer. [ HEIGHTS, MEASUREMENT OF ; 

 BAROMETER.] 



HYSTERIA (from v<rripa, the womb) is, in general language, under- 

 stood to signify those paroxysms to which females are subject, and 

 which are attended with convulsions, a sense of choking, and involun- 

 tary laughing or crying. But the term is used in medicine as a general 

 expression to include a vast number of other symptoms known as 

 " nervous disorders," all dependent on a peculiarly susceptible state of 

 the nervous system. 



We will first consider the different forms of hysteric affection. 



The hysteric fit or paroxysm need scarcely be described, except for 

 the purpose of pointing out how it may be distinguished from fits of 

 other kinds ; and this is a matter of no little importance, not only as 

 regards the treatment required and the temporary alarm of the friends, 

 but also with relation to the happiness and prospects of the sufferer. 

 For it appears that in France, at least, young females labouring under 

 mere hysteria have been separated from their families and society, and 

 placed in confinement under the idea that they were the subjects of 

 epilepsy, a disease which is thought to be hereditary, is but too often 

 incurable, and leads to loss of intellect. The hysteric paroxysm gene- 

 rally commences with the sensation of a ball in some part of the 

 abdomen or in the left side, which rises with a twisting vermicular 

 feeling to the throat, where it induces a sense of suffocation. A tem- 

 porary state of loss of sense and voluntary power succeeds, in which 

 the patient either lies motionless, or is agitated with violent struggles 

 of the limbs ; the head is struck against the bed or floor, and the hair 

 or the breasts are grasped and torn with the hands. Frequently the 

 patient tries to bite herself or the bystanders. The involuntary ex- 

 pulsion of the contents of the bladder not uncommonly takes pkce 

 daring the fit. In the absence of convulsions there is often immode- 

 rate laughter, crying, or singing, and the paroxysm is frequently ter- 

 minated suddenly by a burst of tears. More usually the patient lies 

 quietly for some time after the convulsions cease, and when she re- 

 covers complains of headache. Frequently she proves that conscious- 

 Dais has not been entirely lost, by repeating what has been said 

 by those around her. The attack of epilepsy differs from that of 

 hysteria in not being preceded by any sensation of a ball rising to the 

 throat ; the epileptic patient falls suddenly to the ground, and is 

 immediately violently convulsed ; the eyes are distorted, and the 

 tongue protruded and bitten. In hysteria the features are generally 

 tranquil, and the face is flushed ; whereas in epilepsy it is often of a 

 ghastly paleness. The epileptic fit is in many cases ushered in ly a 

 short cry, but thre is no laughing, crying, or singing during the 



paroxysm, or at its termination, as in hysteria. Lastly, the loss of 

 consciousness is complete in epilepsy, generally not so in hysteria. 

 These are the principal points of difference. It is well to remark in 

 addition that hysteria is almost confined to women, and that the 

 paroxysm is generally preceded by some strong mental emotion ; while 

 epilepsy is most frequent in men, and more usually attacks the patient 

 during the night, or between the states of sleep and waking. Repeated 

 attacks of epilepsy leave imprinted on the countenance a peculiar dull 

 expression which is not seen in the hysterical. 



" Nervous " females are very liable from the slightest causes to 

 hurried respiration, sighing, sobbing, and palpitation; the irregular 

 and hurried breathing may become occasionally so aggravated as to 

 resemble asthma, from which it is to be distinguished by its occurring 

 in young persons, and by its being accompanied by other hysterical 

 symptoms, and a peculiarly irritable susceptible state of mind. 



Merely from a disturbed action of the nerves, and quite independ- 

 ently of all real structural or inflammatory disease, females frequently 

 become distressed by more or less painful sensations fixed in one spot 

 or shifting from one part to another. Violent pain in the head, as if 

 a nail were driven into the forehead, is a very common hysterical 

 symptom. Another frequent seat of the uneasiness or pain is the left 

 side, just below the breast, and this pain is often attended with palpi- 

 tation of the heart, and the patient is unable to lie on that side. 

 Sometimes excruciating pain occupies the whole abdomen. In all such 

 cases it will be found that the disease, simulated by the hysterical 

 affection (whether it be of the head, chest, or abdomen, or of one of 

 the large joints), cannot exist, since other symptoms essential to con- 

 stitute it are absent. The pain of hysteria too, besides being frequently 

 transitory and unfixed in its seat, has generally the peculiarity of being 

 aggravated by the slightest touch of the skin, which is not the case 

 with pain arising from inflammation. With this external tenderness 

 there is frequently great tenderness along the course of the spine, and 

 this is frequently greater at one particular spot. 



Other symptoms of a decidedly hysterical or nervous nature will 

 perhaps be present, or a true hysterical paroxysm may supervene. It 

 is important to know that symptoms of almost every disease may be 

 simulated by hysteria, which, though a troublesome affection for the 

 sufferer, is unattended with danger. It is when real disease is present, 

 and complicated with nervous or hysterical symptoms, that it requires 

 the greatest acuteness of the physician to discern what proportion of 

 the symptoms is of the latter kind, and what due to the more important 

 affection. 



Hysteria sometimes assumes the form of different paralytic affections 

 the power of moving the arm, or the voice, may be lost. These pheno- 

 mena may be of considerable duration, but are ultimately, and often 

 suddenly, recovered from. The state of long-continued stupor which 

 has received the name of " trance " is most commonly hysterical. 

 Different spasmodic affections, as hiccough and spasm of the throat, 

 preventing swallowing, not unfrequently occur in the hysterical state. 

 Then, again, certain disordered states of the senses and mental faculties 

 and feelings occur, as the consequence of uterine or sexual irritation, 

 and are to be referred to hysteria. Such are somnambulism, some 

 kinds of transitory monomania, and those peculiar perversions of the 

 mind manifested in the desire to feign various diseases. The occa- 

 sional occurrence of hysterical paroxysms, the irritable state of mind, 

 the knowledge that the mind has been acted on in a way calcu- 

 lated to excite the affections, and the presence of other phenomena 

 decidedly hysterical, will assist in detecting the true nature of all these 



There is certainly a peculiar state of the system which predisposes to 

 the affections which we have thus cursorily described, for the causes 

 by which they are excited have nothing peculiar in themselves. All 

 the phenomena indicate a disordered state of the nervous system, and the 

 exciting causes are such as act either through the medium of the body 

 or the mind on that system. The susceptible state of the nervous 

 system, which predisposes it when thus acted on to give rise to the 

 various hysteric phenomena, is without doubt frequently connected 

 with or kept up by an excited condition of the uterine system and the 

 sexual feelings ; with no system of organs and no feelings of the mind 

 does the nervous system of females so much sympathise. This con- 

 clusion is confirmed by the fact of hysteria occurring in a great 

 proportion of cases between the age of puberty and that at which the 

 catamenia cease, during which period the uterus is in a state of greater 

 activity than before and after it ; and by the circumstance of its being 

 at the commencement and termination of that period, when the uterine 

 organs are undergoing the greatest changes, and the feelings of the mind 

 connected with them are most disturbed, that the attacks of hysteria 

 are most frequent and violent. It is from their supposed connection 

 with particular states of the uterus that the attacks have derived their 

 name. Other facts, however, show that a predisposed state of nervous 

 system is necessary, for vascular excitement and structural disease of 

 the uterus may exist without giving rise to hysteria ; and that other 

 functions, as those of the digestive organs, being disordered, may act 

 on a susceptible person so as to aggravate the tendency to hysterical 

 symptoms, or even excite them. In some females, having the requisite 

 nervous susceptibility, a mere plethoric state of the body, without any 

 affection of any special organ, will excite hysteria ; the opposite state, 

 deficiency of blood in the body, will have the same effect : anything, 



