DISEASES OF PLANTS. 2i)3 by they may be prevented. Cures for sueli dis- ease- are not known when the ])hint is once badly affected, so attention is given to their prevention. Sanit.irv conditions are necessai-y to keep pLints in a healthy state. In order to prevent tlie spread of phmt iliseases, all aiTccted plants and parts should be collected and burned. All weeds and wayside plants likely to harbor the disease should be destroyed. Many diseases are spread by in- sects, and, as far as possible, these should be combated. Many diseases may be jJrcvented by the thorou;;li and repeated spraying of the plants with a fungicide (q.v.). The theory upon which these act is that the copper or other substances used are detrimental to the germination of the fungus-spores by which the diseases are sjiread. Experience has shown that much of the loss due to some of our most common and destructive plant diseases might have been absolutely pre- vented by the timely and thorough use of fungi- cides, and that at a cost very small indeed com- pared to the loss sustained. BiBUOGR.riiY. Sorauer, Haiidbucli der P/lan-
- eiik)aiikheiteii (Berlin, 189fi) ; Frank. Die
Kraiikliiilcii (irr I'flnincii (Breslau. 1S9.")-9G) ; Tu- beuf and Smith. The Diseases of Plants Induced 61/ Cri/ptoiiumic Fungi (London, IS'JT): Scrib- ner. Fuii(iiis Diseases of the Grojic and Other Plavis (Little Silver. X. J., 1890): Lodeman, The Sprai/ing of Plants (New York. 1896) ; Mas- see, A Texthool: of Plant Diseases (London, 1899) : Hartig and Somerville, Diseases of Trees (London, 1894) : rrillieux, Maladies des plantes agricoles (2 vols.. Paris. 189.5-97); publica- tions of the United States Department of Agriculture, Division of Vegetable Pathology: also many of the reports and bulletins of agricultural experiment stations, lor articles particularly relating to bacterial diseases, con- sult: E. F. Smith, in American Xaturalist (Philadelphia. 1898-99) : Centralblatt fiir Bak- teriologie iiud Parasitenkunde, Zireite Abtheiluni) (•Tena. 1898, et seq.). See Fungicide: Fuxgi, ECOXOMIC. DISEASES OF WHEAT. See Wheat, Dis- E.^SES (11-, DISENTIS, de'sen-tes. A village in Switzer- land. Canton Orisons, situated on the Hither Rhine. .31 li miles southwest of Reichenau. and 3600 feet above sea-level ( Map : Switzerland, C 2j. It is the site of a large Benedictine mon- astery, founded in 614 by the Scottish monk Sigisbert. a disciple of Saint Columba. Popula- tion, in Iltnn. I 100. DISHONOR (ML. dishonor, from Lat. dis-, apart + honor, honor) OF Xegotiable Paper. The refusal or failure of the drawee of a bill to accept, or of the acceptor of a bill or the maker of a promissory note to pay, it at the proper time. If the drawee of a bill of exchange refuses to accept it when duly presented, the holder should give notice at once to the drav.er and in- dor-ers, or he will relieve them from liability on the paper, as a rule. Ordinarily, the drawer of a bill of exchange or a check has funds in the drawee's hands, upon which the bill or check is drawn, and if the drawee refuses to honor the bill or check, the drawer ought to have notice, so that he may withdraw his funds. If a banker dishonors a customer's check by refusing to pay it when the enstomer's account is good for it. he makes himself liable in damages to the customer. DISINFECTANTS. for such an act tends to harm the latter's credit. See Xecotiaulk I'ArEK, and consult the authori- ties there referred to: sec also Bill of Ex- change; Check; Promissory Note; Protest. DISINFECTANTS (from dis-, without + Engl, infict, from OF.. Fr. infecler, from Lat. inficerc, to infect, from i'h, in -1- facerc, to make). A class of sul)stances which have the power of destroying the causes of infectious and conta- gious diseases. In a large proi)ortion of these diseases the causes have been found to be micro- organisms of a vcgflable nature, called bacteria (q.v.). In the rest of these diseases, such micro- organisms are supposed to exist, but 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 dead tissue, or sup- I)uration in the living body. All clothing and bedding, curtains, carpets, etc., W'hich ought to he 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 u]) by tubercular patients read- ily imlveiizes 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 bichloride of mercurv- 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 lie 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 be thoroughly permeated by a disinfectant. For each 1000 cubic 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. Vessels 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 germs of diph- theria, anthrax, or tuberculosis. Formaldehj'de gas has been emiiloyed increasingly as a disin- fectant since 1893, 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 bacteria in a few hours. Formaldehyde does not injure clotliing. fur, paper, leather, photograph's, or rub- ber or metal goods. Dr. W. II. Park, of New York City, indorses the favorable reports on dis- infection of dwellings, carpets, bediling, clothing, and u])holstery with formaldehyde, and advocates this agent for disinfection of ambulances and other convej'ances 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
