Page:The New International Encyclopædia 1st ed. v. 16.djvu/709

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.
*
621
*

QXJINOA. 621 QUINSY. tion. It is sometimes cultivated as a substi- tute for spinach. QUINOLINE, or Lelcolixe, CjH^X. An or- ganic base to which many vegetable alkaloids are chemically more or less closely related. It may be obtained by the distillation of quinine, cinchonine, or similar substances, with caustic potash. It occurs, together with isoquinoline, a substance of the same molecular composition as quinoline, in coal-tar, and in bone-oil, and may be isolated in a somewhat impure state from the fraction distilled over between 230" and 243° C. It is now prepared on a large scale by a purely artificial method, known as Skraup's method. This consists in heating 120 parts of glycerin with 100 parts of strong sulphuric acid, 38 parts of aniline, and 24 parts of nitrobenzene, a some- what violent reaction soon setting in. After the reaction has subsided, the mixture is kept boiling for several hours, then cooled, diluted with water, and subjected to distillation in a current of steam until the portion of the nitrobenzene that has remained untransformed, is completely removed. The quinoline remains fixed in combination with sulphuric acid, but on adding an excess of soda and again distilling in a current of steam, it passes over almost pure; after drying, it may be further purified by fractional distillation. Three chemical transformations probably take place, in sueeessi%'e order, in this process: First, the action of sulphuric acid on glycerin causes the formation of acrolein, C'H2:CH.CH0; next, acrolein com- bines with aniline. C,..H,XHo, vielding acryl- aniline, CAXiCH.CHtCH,; finally, by the oxi- dizing action of nitrobenzene, ar-ryl-aniline loses hydrogen and is converted into quinoline, Ct,H;N. Pure quinoline has a specific gravity 1.005 at 20° C. and boils at 239° C. It is scarcely soluble in water, but dissolves freely in alcohol and in ether. It is a tertiary aromatic base and com- bines with acids to form erystallizable salts. The peculiar odor of quinoline is characteristic. Quin- oline is largely used in the arts, especially in the manufacture of aniline colors. In medicine it is used as an antiseptic and as a substitute for quinine: it has also been found of great value in diphtheria, a weak alcoholic solution of quino- line being applied to the diseased membranes. The chemical constitution of quinoline is repre- sented by the following graphic scheme: two oxygen atoms are directly linked to the ben- zene nucleus, (fiee Cakbox Compounds.) The simplest member of the group is the substance called benzoquinone, which may be readily pre- paied by the action of potassium bichromate and sulphuric acid on aniline; from the mixture ob- tained by this reaction, benzoquinone is extracted with ether; the ether is then distilled ofi', and the residue is purified by sublimation or by recrystal- lization. Benzoquinone has a peculiar, irritating odor; if pure it melts at 116° C. ; its molecular foiTuula is CeHjO,, and its chemical constitution is represented by one of the following graphic formulas : It may be seen that the molecule of quinoline is composed of two nuclei, the benzine nucleus and the pyridine nucleus. The substance iso- quinoline. mentioned above, has a much similar constitution and its chemical properties are much the same as those of quinoline itself; its boiling-point is, however, 241° C, i.e. two degrees higher than that of quinoline; besides, at ordinary temperatures it is solid, its melting- point being about 22° C. QUINONES (from Xeo-Lat., Sp., Port.. Qui- chua quinn. quinine). .

interesting group of 

carbon compounds belonging to the so-called aro- matic series. Theoretically the quinones may be defined as benzene derivatives in whose molecules "K /i" ^c/ QUINQUAB.TICULAR CONTROVERST. See Ahiii.maxism. QUINQUENNIAL PRESCRIPTION (Lat. quinquennialis, from quiiiquennis, of five years, from quinque, five + annus, year). A period of five years allowed by the law' of Scotland within which payment of sums on all bargains concern- ing movables, arrears of rent in some leases, multures, ministers' stipends, arrestments, must be enforced. QUINSY ( formerly also quincy, squincy, from OF. squininicie. esquinance, Fr. esquinancie. from Lat. cynanche, from Gk. Kvydjxv, h-ynanche, sort of sore throat, from kvup, kyon, dog -t- fivxcii', anchein, to choke). An acute inflammation of the loose tissue surrounding the tonsil, termi- nating usually in suppuration. Quinsy is most prevalent between the ages of fifteen and forty, children and old persons seeming to be exempt. A rheumatic tendency predisposes to the disease. The exciting cause is sudden and imequal ex- posure of the body to cold or wet. The affection is usually confined to one tonsil, but both may be successive or simultaneotisly involved. One at- tack predisposes to others. The disease is ushered in with feelings of chilliness and ex- haustion followed by a temperature of 102° or 103° F. These symptoms are accompanied by severe pain in the region of the tonsil. The latter becomes so swollen as to interfere with deglutition. The mouth can only be partly opened and with great pain, and the taking of food, except in liquid form, becomes impossible. The peritonsillar tissues become swollen and- painful. The voice is muffled and indistinct, and sleep is almost impossible. Severe cases are marked by an intensity of all these symptoms, successive chills and sweats, delirium at night. Although the disease is acute and painful, it rarely proves fatal. Cases have occurred in which bursting of the abscess into the larynx during sleep produced instant death. The or- dinary duration of suppurative tonsillitis is from five to eight days. At the end of this time the abscess bursts, all the symptoms disappear, and prompt recovery ensues. In its early stage the affection may often be cut short or aborted if prompt measures for relief are taken. These consist in rest, free purgation by a saline cathar-