DISINFECTANTS. 294 DISMAL SWAMP. exposing tlioni lo foniialdcliyde pus. The latter dws nut ■lull kern edges. Surgeons' hands and arms are sterilized by washing with soap and nailbrush, and then with a solution of perman- ganate o£ potash or of biehloride of mercury. The fivces of tvphoid and cholera iiatients, and the sputa of patients sulTering with tubercu- losis inlluen/.a jineumonia. etc., should he dis- infec'ted with a 5 l>er cent, solution of fresh chloride of lime or a 5 per cent, solution of crude earl>olie acid. Either of these disinfectants is useful in disinfecting privy vaults or accumula- tions of sewage. rero.ide of hydrogen is used in disinfecting suppurating wounds in some cases. Chloride of zinc and chlorine pas, as well as cer- tain patented derivations of the refuse resulting after distilling kerosene from crude petroleum, arc used in special cases for disinfection. Heat .M) C'oi.d. It nuist, however, be remem- bered that the best disinfwUint of all is heat. Articles of clothing that can be washed are easily disinfected by the use of boiling water. Other articles mavbe subjected to baking, or to ster- ilizing by the u.se of steam inder pressure. Dry heat penetrates very slowly. Ovens for disin- fection, called sterilizers, are arranged in hospi- tals, into which steam at a temperature of about 225° F. is admitted under pressure for the treat- ment of clothing and bed-coverings. Similar cylinders are constructed for the use of health departments in large cities. Cold kills the bac- teria of cllow fever, but not those of anthrax, smallpox", or tvphoid fever. See Bactioria ; Co>-- TAi.iox ; Infection ; Disea.se, Oerm Theory of. DISK (Lat. discus. Ok. SIckoc, dL<:l:os, disk). A word of various application among plants. . iong Comi>osit:P (sunflowers, asters, rt"") >* refers to the central part of the head in which the showv corollas do not occur as at the margin. In other "groups it refers to a ring-like structure developed" within the (lower, from which certain of the (loral parts often arise; or to a disk-hke structure upon the top of the ovary in certain epig ous flowers. See Flower. DISLEKE, df'slar', Paul (1840—). A French engineer and administrator, born at Douai. He studied at the Ecole Polyteehniquc, and in ISfil entered the naval engineers. In 1S88 he became an engineer of the lirst class. From 1868 to 1871 he was in charge of the arsenal at Saigon, French Indo-China: in 1881 was ap- pointed a Councilor of State: and in 18S2 re- ceived the post of colonial director in the Minis- try of Marine lie was transferred in 18fll to tli"e directorship of foreign commerce. His Traill' dc Uqishition colonialc (188fi) is regard- ed as authoritative. His works further include: l.'i <itttire d'escadre et la guerre des cOtes ( 18iC) ; Ktiidcs de statistiquc ; Les budncls militaircs de la France ct dc I'Anfilrlerre (1878); and Le service tnilifairc aux colonies (1889). DISLOCATION (Fr. dislocalion. from ML. disclwdrr. to ilisln.ate, from Lat. dis: apart + locare, to place, from lorii.s, place). . displace- ment of one bone from another with which it forms a joint ('put out of joint' being the popu- lar expression). Dislocations are generally the result of accident, hut may also be the result of disease, or mav be congenital. The displacement may be partial" or complete, and surgeons classify their cases into simple dislocations when the Bkin remains unbroken, and compound when there is a wound by which the cxlernal air may eom- municale with the joint, (.tccasionally. in addi- tion to the dislocation, there arc fractures of the bones, or lacerations of importjiiit l>hK)d-ve8- sels in the neighhorhood : the dislocation is then said to be •complicated.' Dislocation is a rare accident in infamy :iiid in old age: because in the former the joint-ends of the liones are very llexible and vield to violence, while the aged skeleton is so' rigid that the brittle bones frac- ture under force that would drive y.aingcr and lirmer ones out of their sockets. Dislocations are most frequent between the ages tpf thirty and sixtv. Persons with weak muscles, and lax, long ligainents, in- tho-e in whom the latter have been strftened by inllammation of the joint, are pre- disposed to dislocation. The joints most fre- qucntlv displaced arc the shmihler and the elbow. General Symptoms, .ftcr a blow, fall, or violent muscular exertion, a limb is found to be immovable at the injured joint; there is great pain, and the shape of the part is ehang.d; but soon swelling ensues, and every distinctive mark about it is obscured. If left alone, or merely treated as an inllamcd joint, the swelling gradu- ally subsides, but the immobility continues, the limb is crijipled for months or years, when at last Nature may form a new socket for the end of the bone, and" some amount of useful motion is restored. The proper shape of the part is never restored, but remains an eyesore lo the patient and a disgrace to the surgeon. Treat.ment. The general treatment of dislo- cations consists ill reduction or replacement of the bone into its original position. Us return is opposed bv the muscles attached to it, which are stimulated to contraction by the pain of the operation, the latter requiring, of course, the application of considerable force, lleduction is accomplished bv two methods — manipulation and traction, in using the former the surgeon endeavors first to relax those muscles wliuli l>.v tbcir contraction prevent the return of the he.id of tile bone into its proper position, and then by certain movements to cause the Ixme to retrace tlic path bv which it escaped from the socket. When manipulation is unsuccessful, the attempt is made to overcome the resisting p.iwer of the muscles by traction. AVhen this is fully done the bone usuallv slips easily into its idace, with per- haps some "guidance from the hand of the sur- geon Too great violence in traction, however, must never be used, as injury to surrounding tissues, or fracture, may result. In cases which do not readilv reduce, an:esthesia must be re- sorted to in o"rdcr to produce ccmiplete mus<'Ular rela.xation. The subsequent treatment consists in rest, with splints or bandages to prevent a recurrence of the dislocation while the rent in the jomtcap- sule is healing. Four to six weeks arc usually necessarv for the accomplishment of this proc- ess Th'e treatment of ccmgcnital and iiatholog- icai dislocation is jialliativc. and rnpiiics the use of some special apparatus, although at timra operation may give a new and serviceable joint. DISLOCATION (ix GEOLO(iY). See Favlt. DISMAL SWAMP. A swamp fomierl* iibout -40 miles long bv 2r, miles wide, lying chief- Iv in Virginia, and partly in North Oarolina (Map: Virginia. H .->). In its centre is LaM Drumniond. about square miles m area. lil»»
