Page:The American Cyclopædia (1879) Volume IV.djvu/109

 CATAPLASM CATARACT 101 half partly hilly and partly mountainous. Only a small portion is watered by small rivers. The chief products are vegetables, chestnuts, acorns, inilk, cheese, butter, silk, wool, hemp, lumber, oil, and wine. It has several coal mines and mar- ble quarries. II. The capital of the province, situated on a mountain near the gulf of Squil- lace, 30 m. S. S. E. of Cosenza ; pop. in 1872, 24,901. It is the seat of a bishop, and has a cathedral, several churches and convents, a cas- tle, a royal academy of sciences, and numerous schools and charitable institutions. Consider- able trade is carried on in cattle, corn, and wine, and there are manufactures of silk vel- vet, embroidery, and carpets. It suffered se- verely from the earthquake of 1783, which overthrew some of the principal buildings. CATAPLASM (Gr. KaTaxXdaaeiv, to spread over, to plaster), a poultice or soft substance applied externally to some part of the body, either to repress inflammation and allay pain, or to pro- mote inflammation or its consequences, and lessen the pain attending it. For the former purpose it is applied cold, and often contains a preparation of lead to increase its astrin- gent and refrigerating power; for the latter it is used at different degrees of temperature. When intended to hasten the progress of in- flammation and lead to suppuration, poultices should be of as high a temperature as the part will bear, but of a lower temperature when used as mere emollients. Cotton wool, steeped in water, and bound to the part with a light bandage, is a very simple and efficient applipa- tion, in most cases where a cold poultice is re- quired to allay pain and repress inflammation. Warm poultices may be made of bread, slip- pery elm bark, or flaxseed meal. CATAPULT (Gr. Kara, against, and ir&Ueiv, to hurl), an ancient military engine for throwing stones, darts, and other missiles, invented in Syracuse in the reign of Dionysius the Elder. It acted upon the principle of the bow, and consisted of wood framework, a part of which was elastic, and furnished with tense cords of Catapult. hair or gut. Catapults were of various sizes, being designed either for field service or bom- bardments. The largest of them projected beams 6 ft. long and weighing 60 Ibs. to the distance of 400 paces, and Josephus gives in- stances of their throwing great stones to the distance of a quarter of a mile. The Romans employed 300 of them at the siege of Jerusa- lem. From the time of Julius Caesar it is not distinguished by Latin authors from the lal- lista, which was originally used only for throw- ing masses of stone. CATARACT, a disease of the eye in which there is an opacity of the crystalline lens or of its capsular investment. It is most common in old persons, in whom it seems to be the natural consequence of age ; but it also occurs in infants, and is even congenital ; it appears to be more frequent in cold and damp climates than in warmer regions, and it is certainly hereditary in many instances. Among the exciting causes, especially of the capsular form, are wounds and inflammations of the internal eye ; but the ordinary cause is the diminished nutrition of the organ in common with others in advancing age. True cataract may be either lenticular, capsular, or capsulo-lehticular, according as the seat of the opacity is in the lens itself, in its capsule, or in both at the same time. Certain cases of opacity external to the crystalline ap- paratus have been called false cataracts, and may be caused by the effusion of lymph, blood, or pus, or by false membranes ; secondary cata- racts are those which follow the surgical opera- tions for the extraction or depression of the lens. The lenticular cataract may vary in hardness from stony to gelatinous ; its opacity is rarely uniform, being generally thickest in the centre and thinnest on the edges ; in some cases the opacity begins at the circumference in rays which slowly converge to the centre ; the color varies from pearly white to amber yellow. The capsular cataract, which Velpeau considers more common than the lenticular, offers a great variety of colors and streaks, and may occupy either the anterior or posterior surface, or both. In the last form of cataract both the lens and its capsules are involved, with the varieties common to both. The physical sign of cataract is a more or less troubled appearance behind the pupil, of a yellowish color, deepest in the centre, and becoming more distinct as the disease progresses ; the rational sign is a gradual diminution of vision, accom- panied by the sensation as if a cloud, specks, spiders' webs, or snowflakes were passing be- fore the eyes ; objects are seen best in certain positions of the head, as when turned on one side, and during the evening or in the shade when the dilated iris permits more light to enter the pupil; on looking at a candle the flame appears surrounded by a thick bright haze. The progress of the disease is very slow, generally unaccompanied by fever, pain, or any disturbance of the general health. It is very rare for a person to be unable to distinguish day from night. M. Sanson has proposed an excellent catoptric test for the detection of cataract by the reflection of light. When a lighted candle is held before the eye of a