DISINFECTANTS (from dis-, without + Engl. inject, from OF. Fr. injecitT. from Lat. in/let-re, to infect, from in, in + faccre, to make). A ,'lass of substances which have the power of destroying the causes of infectious and conta gious diseases. In a large proportion of these diseases the causes have been found to be miero organisms of a vegetable nature. called bacteria (q•v•l• In the rest of these diseases, such micro organisms are supposed to exist. loot have not yet been identified. Disinfectants are used to destroy these germs or to stop infection. The term deodorants is applied to substances that dissipate or destroy foul smells, but do not neces sarily destroy germs; and the term antiseptics is applied to substances that prevent the growth especially of those bacteria which cause fermen tation or putrefaction of deal tissue, or sup puration in the living body.
All clothing and bedding, curtains, carpets, etc., which ought to be disinfected should be kept moist until completely sterilized, for the bac teria and their spores are easily scattered in the dust arising from handling dry articles. The mucus coughed up by tubercular patients read ily pulverizes and mixes with the dust when dry, thus endangering any one who may inhale the dust-laden air of an infected room. All dust which has settled in cracks, on woodwork or furniture of an infected room, should be removed by wiping it up with cloths wet with a solution of biehloride of mercury and water, 1 to 1000; or a 3 per cent. solution of carbolic acid in water; and the cloths should be burned afterwards. The same solution may be used in washing all walls and woodwork. Boards of health advise that apartments, after being thus treated, should be fumigated with sulphurous acid, that all cracks may he thoronghly permeated by a disinfectant. For each MOO cultic feet of space, 4 pounds of sulphur is placed in an iron pan, which is placed upon a brick, which, in turn, stands in a tub of water. Vessel, of boiling water are placed about the room. The sulphur is then light ed and the room closed air-tight. This method is useful in eases of smallpox, scarlet fever, and measles, but it does not kill the plans of diph theria, anthrax, or tuberculosis. Formaldehyde gas has been employed increasingly as a disin fectant since 1...+93, as generated by special ap paratus from formalin pastilles. Two grams of formalin for every 35 cubic feet of room space has destroyed anthrax. tubercle, diphtheria and typhoid bacilli, streptococcus, and other baeteria in a few hours. Formaldehyde does not injure clothing. fur, paper, leather. photograph's, or rub ber or metal goods. Dr. NY II. Park, of New York City, indorses the favorable reports on dis infection of dwelling:, carpets, bedding, clothing, and upholstery with formaldehyde, and advocates this agent for disinfection of ambulances and other conveyances which can be tightly closed, the gas to be used in the proportion of 10 per cent. by volume, the time of the exposure to be not less than one hour.
Surgeons' instruments are disinfected (or, rather, sterilized) by boiling them in water con taining 2 per cent. of bicarbonate of soda, or by exposing tlwin to formaldehyde gas. The latter does not dull keen edges. Surgeons' and arms are sterilized by washing with soap and nail-brush, and then with a solution of perman ganate of potash or of bichloride of The Idees of typhoid and chob-ra and the sputa of patients suffering w ith tubercu losis. influenza pneumonia, ete., should he dis infcctvil xvith a 5 per cent. solution of chloride of lime or a 5 per cent. solution of crude carbolic acid. Either of these is useful in disinfecting privy vaults or aceuttitila tint!, of SI•;lage. Peroxide of hydrogen is used in disinfecting suppurating wounds in some ruse-. Chloride of zinc and chlorine gas, as well as •er tain patented derivations of the refuse resulting atter distilling kerosene from erode petroleum, are used in speeial eases for disinfection.
11F..kr AND Cohn. It must, however, be remem bered that the best disinfectant of all is of that can In' are easily disinfected by the use of boiling water. Other articles may be subjected to baking, or to ster ilizing by the use of steam under pressure. Dry heat penetrates very slowly. Ovens for disin fection. called sterilizers, are arranged in Lospitats, into which steam at a temperature of about 225' F. is admitted under pressure for the treat ment of clothing and bed-coverings„ vonstructed for the use of health departments in large cities. ('old kill, the bac teria of yellow fever, hut not those of anthrax, smallpox, or typhoid fever. See ItAcriattA; CON T.1GION ; INFECTION ; DISE.\ SE. “EltNI TIIEORY DISK (Lat. discus, (:k. afaxor, disko.v, disk). A word of various application among plants. .‘inong Composite:esters. etc.) it refers to the ventral part of the bead in which the showy corollas do not °rem- as at the margin. In other groups it refers to a ring-like structure developed within the flower, front tvltirh certain of the floral parts often arise: or to it disk like structure upon the top of the ovary in certain epigynou, flowers. See Ft.owEit.
DISLtRE, t•L ( I gin—) . A hrrurh engineer and administrator, born at Itonai. Ho studied at the Ecole Polytechnique, and in Isull entered the naval engineers. in ISsS; he becatne an engineer of the first class. From to IS7 I he was in ('barge of the arsenal at Saigon, French Indo-China; in 1S8I was ap pointed a Councilor of State; and in Isti2, re eeived the post of colonial director in the 'Nlinis try of Marine Ile was transferred in Is91 to Ilie directorship of foreign eonimerce. Ills Trftitt' rlr liqislatimt eolonialt. (1SSII1 is regara •d as authoritative. His works further inelude: 1,a quo err d'r seallre et qurrre rb's (•1;tf•R Eludes Ile Lcs btr(lpf Is wililaires dr ill POI gleterre (IS78): and 1,e r•ie, ait.r robmies (1SS9).