Page:Encyclopædia Britannica, Ninth Edition, v. 6.djvu/577

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on the ground, is proceeded with. The eggs, from seven to fourteen in number, are about 1/ inches in length and an inch in breadth, and are of a slightly reddish-white colour spotted and speckled with reddish-brown. The young crakes are covered at first with a black down, but soon assume their feathers, and are able to fly in six weeks. The upper plumage of the male is for the most part a yellowish-brown, each feather being marked with a central streak of a darker colour, and the under surface a pale buff- transversely barred with reddish-white. The Corn Crake, or Land Rail, as it is sometimes called, feeds on snails, slugs, worms, and seeds. It is a shy and timid bird, seeking safety in concealment among the rank herbage which it frequents, and through which it runs with amazing rapidity j its note may thus be heard in quick succession proceeding from the most diverse parts of the same field, a circum stance which seems to have suggested the idea that the crake possessed for protective purposes a certain ventriloquial power. It seldom takes wing unless driven to it, and then flies slowly, with its legs hanging down, to the nearest place of concealment, and is thus much oftener heard than seen. In common with many other animals it is said to feign death as a means of avoiding a threatened danger. As an article of food the Corn Crake is regarded as a great delicacy. The Spotted Crake (Ortygometra porzana), a smaller and more aquatic species, is much less common in Britain than the former, from which it is readily distin guished by the numerous white spots on the upper surface of its plumage. It breeds on marshy ground, frequently at the water s edge. The Little Crake and Baillon s Crake

both occur in Britain as rare summer visitors.

CRAMP, a painful spasmodic contraction of muscles, most frequently occurring in the limbs, but also apt to affect certain internal organs. This disorder belongs to the class of diseases known as local spasms, of which other varieties exist in such affections as spasmodic asthma and colic. The cause of these painful seizures resides in the nervous system, and operates either directly from the great nerve centres, or, as is generally the case, indirectly by reflex action, as, for example, when attacks are brought on by some derangement of the digestive organs.

In its most common form, that of cramp in the limbs, this disorder comes on suddenly, often during sleep, the patient being aroused by an agonizing feeling of pain in the calf of the leg or back of the thigh, accompanied in many instances with a sensation of sickness or faintnesa from the intensity of the suffering. During the paroxysm the muscular fibres affected can often be felt gathered up into a hard knot. The attack in general lasts but a few seconds, and then suddenly departs, the spasmodic contrac tion of the muscles ceasing entirely, or, on the other hand, relief may coma more gradually during a period of minutes or even hours. A liability to cramp is often associated with a rheumatic or gouty tendency, but occasional attacks are common enough apart from this, and are often induced by some peculiar posture which a limb has assumed during sleep. Exposure of the limbs to cold will also bring on cramp, and to this is probably to be ascribed its frequent occurrence in swimmsrs. Cramp of the extremities is also well known as one of the most distressing accompaniments of cholera. It is likewise of frequent occurrence in the process of parturition, just before delivery.

This painful disorder can be greatly relieved and often entirely removed by firmly grasping or briskly rubbing the affected part with the hand, or by anything which makes an impression on the nerves, such as warm applications. Even a sudden and vigorous movement of the limb will often succeed in terminating the attack.

What is termed cramp of the stomach, or gastralgia, usually occurs as a symptom in connection with some form of gastric disorder, such as aggravated dyspepsia, or actual organic disease of the mucous membrane of the stomach, and must be dealt with in reference to those particular ailments.

The disease known as Writer's Cramp, or Scrivener's Palsy, is a spasm which affects certain muscles when engaged in the performance of acts, the result of education and long usage, and which does not occur when the same muscles are employed in acts of a different kind. This disorder owes its name to the relative frequency with which it is met with in persons who write much, although it is by no means confined to them, but is liable to occur in in dividuals of almost any handicraft. It has been termed by Dr Duchenne Functional Spasm.

The symptoms are in the first instance a gradually increasing difficulty experienced in conducting the move ments required for executing the work in hand. Taking, for example, the case of writers, there is a feeling that the pen cannot be moved with the same freedom as before, and the Jiandwriting is more or less altered in consequence. At an early stage of the disease the difficulty may be to a large extent overcome by persevering efforts, but ultimately, when the attempt is persisted in, the muscles of the fingers and occasionally also those of the forearm, are seized with spasm or cramp, so that the act of writing is rendered impossible. Sometimes the fingers instead of being cramped move in a disorderly manner and the pen cannot be grasped, while in other rare instances a kind of paralysis affects the muscles of the fingers, and they are powerless to make the move ments necessary for holding the pen. It is to be noted that it is only in the act of writing that these phenomena present themselves, and that for all other movements the fingers and arms possess their natural power. The same symptoms are observed and the same remarks apply mutatis mutandis in the case of musicians, artists, compositors, seamstresses, tailors, and many mechanics in whom this affection may occur. Indeed, although actually a rare disease, no muscle or group of muscles in the body which is specially called into action in any particular occupa tion is exempt from liability to this functional spasm. Hence the cause has been ascribed to over-use of the parts concerned, although this is regarded as doubtful by many high authorities, since cases have been observed where there had been no excessive strain upon the function of the affected muscles, hile again in persons who pursue their special occupation, even to the utmost possible amount of fatigue, the symptoms of this disorder are exceedingly rare. It is, however, difficult to account for the phenomena on any other theory, and at all events the complaint is greatly aggravated by over- exertion of the parts.

In the treatment of this complaint the only effectual remedy is absolute cessation from the work with which the attack is associated. It is sometimes recommended that the opposite hand or limb be used so as to afford the affected part entire rest, but this is generally followed with the extension of the disease to that locality also. Peculiar forms of penholder and other mechanical contrivances have been suggested so as to enable the occupation to be carried on, but they do not afford any relief to the disease, for tie cure of which the only means that can be relied on is entire rest.

(j. o. a.)
CRANACH, Lucas (1472-1553), one of the represen

tative painters of Germany at the time of the Reformation, was born at Cronach in Upper Francpnia, and learnt the art of drawing from his father. It has not been possible to trace his descent or the name of his parents. We are not informed as to the school in which he was taught, and it is a mere guess that he took lessons from the South German masters to whom Mathew Grunewald owed his education.

But Grunewald practised at Bamberg and Aschaffenburg,