Page:The New International Encyclopædia 1st ed. v. 06.djvu/282

DIGEST. 238 DIGESTION. in condensed form; ijartit-ularly, llie authorita- tive compilation of the civil law, otherwise known as the Pandects, made under the author- it,v of .Justinian ID30-533). See Civil Law; Code; 1'axdects. In English and American law the term is ap- plied to a great number and variety of legal works of reference, ranging from such encyclo- jiirdie collections of special treatises as Bacon's and 'incr's Abridgments and Comyn's Digest, to the alphabetical arrangements of statutes and of case law which have monopolized the title in recent years. The former kind of digest was a favorite form of legal autliorship in the earlier period of the common law, and several of these compilations — as tho.se of Slatham (about 1470), Fitzherbert (lolG), Brooke (1568), and RoUe (16C8) — long maintained a high position as legal authorities. The earliest of these arc still useful as containing references to cases as yet buried in the Year-Books and other early reports. As authorities, however, the.v have all been supcrscdi'd in the estimation of lawyers by more systematic treatises. The modern digest of case law is in efTect an elaborate inde. to the enormous collections of judicial decisions in which the common law of Great Britain and of the I'nited States lies imbedded. The most authoritative of the Eng- lish digests are those of Fisher and Chitty. Each American State has one or more of such compila- tions, of which Abbott's Encyclopa-dic Digest of New York decisions is perhaps the most exten- sive and complete. There are also digests of the Federal reports, of the United States statutes, and a comprehensive compilation of all the Federal and State reports, known as the Century Digest. The plan of all these digests of case law is substantially the same, consisting of an alpha- betical arrangement of legal titles, under which are given brief statements of the rule or doctrine enunciated in each decision, together with the title and location of the case in which the deci- sion was rendered. (See .VnRinr.MK.NT : RKroRT.) Consult: Wambaugh. The Sliujii <if Cases (2d ed., Boston, 1894): Lindley, •The History of Law Reports," Law Quarterly Review (London, 1885). DIGESTEB. A name originally applied to a strong lioili r. with a closely fitting cover, in which l)oncs or other animal substances, placed in water, could be raised to a temperature above the boiling point, or 212° F. The word is now given a wider meaning: the malerial may be placed in some liquid other than water, and chemical action instea<l of heat may be used to efTect the disintegrating prix'css. The digester, in its simplest form, was invented in 1081 by Denis Papin (q.v.). a French scientist. It is made of iron or other metal, and has an air-tight cover, proided with a safety-valve, from which steam may be allowed to escajie when the pres- sure becomes loo great. The increased pressure to which the contents of the boiler are exposed raises them to a much higlier temperature than could he secureil in an open vessel, reaching at times 400° F. At such a temperature bones will dissolve. In its modern form, (he Papin digester is put to much wider uses than (he mere prep- aration of soup and ex(rac(ion of gelatin from bones, for which i( was originally intended. One applica(it>n of the invendcm is (he lard or grease tank, which is an esscnli:il fea(nre of a large , modern slaugliter-house. Into such tanks the carcasses of animals too |)oor for the regular market and llic cntiails and grease yielding olfal of other animals are thrown. Steam is applied, which resolves the contents of the tank into fat; water, which contains much soluble matter in .solution; and mud, containing earthy and solid particles, the contents arranging themselves in layers, from top to bottom, in the order named, according to their spccilic gravity. The tank is usually a vertical cylinder, with a perforated false bottom, which holds the charge and at the same time allows the water of <'Oiidensa(ion to percolate into the lower chamber. There is a discharge hole at the bo(toni for removing the residuum, and a number of try-cocks are ar- ranged along the sides, by means of which the level of the fats and water may be a.scertained. There may be two discharge cocks; through the higher one the lloating fat may be decanted and tliroiigh the lower one the water may he drawn oil', as the contents and stale of the (irocess require. In some forms of digesters, like those for treating garbage, the waler and grease may be drawn oil' together, and separated afterwards. The solid matter, called tankage, may be pressed or dried, or both, and is oftentimes utilized for various purposes. A familiar example of a chemical digester is the apparalus for extracting tannin from nut- galls by means of ether. The nut-galls are placed in a vessel saturated with ether; tlic volatile extract falls into a closed vessel placed below and cuniiccted by means of a jiipe with the top of the other vessel, to prevent the escape nf the ether. DIGESTION IX Animals. See Food. DIGESTION (Lat. di(ieslio. from ditjcren-. to digest) i.N Pl. t.s. The process by which foods are rendered lit for absorption, conduction, or assimila(ion (qq.v.). Foods are somelimes in- soluble in waler. or, when solulile. need to be altered to make them more readily dilfusible or usable. Since no subslances can be absorln-d except in solution in water, and since pro(oplasin and cell-walls offer resistance to the movement of foods having large molecules, digestion is necessar.v. There are no special digestive organs in plants corres])f)nding (o (he alimentary tract of animals, and cnnqiarisun of leaves to the stomach is entirely misleading. Digeslion may occur outside the plant body to make foods soluble and prepare (hem for absorption. Or it ma.v occur in the interior of any cell of any organ, (hough it is naturally most active in those cells which contain the largest quantities of foods that are to be rendered available for growdi and repair. Tn bo(h cases digestion id ! accomplished by the protoplasm. Doubtless the protoplasm may act direedy. bill in most cases il di'_'e~(s foods by .secreling enzymes (q.v.) (o do (he work. Enzymes may he j>roduced in all (he cells of an organ, e. g. in leaves, tubers, the mycelium of a fungus; or in certain cells, free of reserve food. e. g. nasdirtium and other Cm- cifene: or in definite groups of cells constitut- ing a gland (q.v,), e. g. panlen nasturtium: or in a glandular epidermis, e. g. on the embryo of grasses; or in superficial glands, e. g. saxi- fragr and insectivorous plants. (Sec Secre- tion.)