Page:Collier's New Encyclopedia v. 03.djvu/424

LEFT DIOSCUBl 370 DIPHTHEBIA plant of the Cape, or elephant's-foot. Tamus communis, black bryony, is com- mon in hedge-rows. DIOSCURI (di-os'ku-ri), the classical name for Castor and Pollux, twin broth- ers (Pollux being the son of Zeus) and tutelary deities of wrestlers, horsemen, and navigators. Their transplantation to the sky as one of the 12 constellations of the zodiac (the Twins) is a celebrated allegory of mythology. They are some- times styled Tyndaridae, because Tynda- rus was the nominal father of both, DIOSMA, a genus of plants, belonging to the Rutaceaz or rue family. They are small shrubs with white or red flowers; leaves alternate or opposite, simple. They are remarkable for their overpowering and penetrating odor, arising from the presence of a yellowish volatile oil. They are the Bucku plants of the Cape of Good Hope. The plant has been employed in chronic affections of the bladder and uri- nary organs in general, and has also been administered in cholera. DIOSPYROS, a genus of plants be- longing to the natural order Ebenaeese. They consist of trees and shrubs, with white or pale yellow flowers. D. lotos is the Indian date plum, and is supposed by some to be the lotus of the ancients. The trees of several of the species furnish ebony wood. The fruit of D. kaki is oc- casionally brought from China as a dry sweetmeat, and D. virginiana is the date plum, the bark of which is employed as a febrifuge, along the Mississippi, in cases of cholera infantum and diarrhoea. A kind of cider has been made from this fruit, and a spirituous liquor distilled from its fermented infusion. DIP, the inclination or angle at which strata slope or dip downward into the earth. This angle is measured from the plane of the horizon or level, and may be readily ascertained by the clinometer. The opposite of dip is rise, and either ex- pression may be used, according to the position of the observer. DIPHTHERIA, a contagious and (in its severe forms) malignant disease, caused by a specific bacillus and gen- erally characterized by the formation of a fibrinous false membrane in the throat. Although previously observed, it was first clearly described in 1826 by M. Breton- neau of Tours under the name of "diph- terite," as a form of very fatal sore throat occurring chiefly in children. It is now known that most cases of mem- branous croup are identical with diph- theria. The period of incubation is usually from two to seven days. The disease be- gins by malaise, feeling of chilliness, loss of appetite, headache and more or less fever; soon the throat feels hot and pain- ful and the neck is stiff and tender. If seen early, the throat is red and swollen, but a false membrane of yellowish or grayish color quickly appears in spread- ing patches, usually first on the tonsils, whence it often spreads to the pillars of the fauces, uvula and back of the throat, and may even extend down the oesopha- gus or gullet; extension of the membrar.e into the nasal cavities is a grave symp- tom. There is usually enlargement of the glands at the angle of the jaw, and albuminuria generally occurs at some stage of the disease. Diphtheritic mem- brane may be formed on any mucous sur- face, or even on a wound; if it extends into the larynx it gives rise to cough and difficulty in breathing. The throat af- fection is often accompanied by a low and very dangerous form of fever, vdth quick, feeble pulse and great and rapid loss of the patient's strength, which is still further reduced by the inability to take food; in other cases, the disease is fatal by paralysis of the heart or by suf- focation, due to invasion of the larynx. Invasion of the larynx may necessitate intubation or tracheotomy. After the acute disease is over, the recovery may be delayed by paraljrtic symptoms of vari- ous kinds; or simply by extreme debility with exhaustion and loss of appetite. In the early stages of convalescence there is danger of sudden heart failure upon exertion. Diphtheria is contagious. It may occur as a complication of scarlet fever, mea- sles, and other infectious diseases. All gradations in the intensity of xhe disease from mild sore throat to septic and gan- grenous forms occur. Damp and tem- perate climates seem to favor its develop- ment. Insanitary conditions favor its oc- currence, but the disease may appear under the most favorable hygienic sur- roundings. True diphtheria is now known to be caused by a specific bacillus called bacil- lus diphthericB, or the Klebs-Loffler ba- cillus. Thif bacillus was first recognized by Klebs in 1883 by microscopical exami- nation of diphtheritic membranes, but it was first successfully cultivated by Loffler in 1884. Its causal relation to the dis- ease was not thoroughly established till the investigations of Roux and Yersin in 1888, who demonstrated the existence of a peculiar and intensely poisonous sub- stance known as the diphtheria toxin. It is now generally admitted that the Klebs- Loffler bacillus is the cause of true diph- theria. The diphtheria bacillus is a slender rod characterized especially by ir- regularities in shape and staining with aniline dyes.