S IN LATIN. 



m 





Hut wit!i / >. n.-i.' it fornm a compound of a buff colour 

 whi'-h ia the ban! 



resent tho oommoroial value of gelatine. Th 

 parings of hides, tho oars and hoofs, etc., are H tee pod ir. lim<- 

 lovo tho hair and other impurities ; they aro then 

 exposed to thu air, that the limo may become carbonate, an 

 thus innoxious. When washed thoy aro introduced into a coppe 

 with a false perforated bottom ; tho water is boated by injection 

 of steam. As soon as a portion of the liquid gelatinises on 

 cool iri},', tho copper ia emptied, and tho liquid allowed to cool 

 i supply of water is added to tho copper; this produces 

 an ii;tVrior kiiul of gluo, while the product of tho third dilution 

 Is site. Tho process of drj-inj? tho gluo is the most delicate par 

 of the manufacture. The soft gelatinous mass is out into slices 

 by wire, and those are exposed to the air on nets. But a sudden 

 rise of temperature will liquefy tho whole ; a frost or a fog wil 

 bo equally injurious. The marks on a cake of glue are from tho 

 meshes of tho not. 



Leather is mode by steeping tho skins in lime-water, anc 

 removing tho hair by scraping. They are next submitted to the 

 action of a very dilute solution of sulphuric acid, which clears 

 thorn of lime and opens the skin to the action of the tan. The 

 '"tanning" is a long process; oak-bark is used to supply the 

 tannio acid ; this combines with the gelatine in the cuticle, 

 forming leather. 



The leather used for boots and shoes undergoes the process 

 of currying, by which it is impregnated with oil, which renders 

 it more supple and impervious to moisture. 



Chondrine may bo distinguished from gelatine by becoming 

 coagulated by vegetable acids and by alum. It is produced by 

 boiling any of tho cartilages; its solution gelatinises on cool- 

 ing. There is reason for believing that chondrine oxidises into 

 gelatine. 



Osseine is tho gelatine procured from bones. The composition 

 of this group is given in the following table : 



GELATIGENOU8 GROUP. 



The liquids which circulate through animals may be divided 

 into three classes: (1.) Those which are secreted by various 

 glands, and aid the progress of digestion. (2.) Those which are 

 the products of digestion, as blood and milk. (3.) Those which 

 come away from the body, carrying off the used-up material. 



(1.) The saliva is secreted by glands in the neighbourhood of 

 the mouth, and is poured into the food during the process of 

 mastication. It contains a very active principle, ptyaline, which 

 can convert starch into sugar. Its inorganic constituents are 

 salts of sodium, potassium, and calcium, together with lithates 

 of the alkalies. These are sometimes deposited on the teeth, 

 forming tartar. 



Gastric juice is secreted by the lining membrane of the 

 stomach, whence it issues to carry on the work of digestion 

 that is, of rendering the food soluble. Its active principle ia 

 pepsin, which has a remarkable solvent power on albumen. 

 When the process of digestion is going on, the gastric juice 

 contains a free acid which, according to Miller, is a mixture 

 of hydrochloric and lactic acids. The saline constituents are 

 chlorides of calcium, sodium, and magnesium, sodic lactate, and 

 a trace of phosphates of lime and iron. 



The pancreatic fluid is the product of the pancreas the 

 sweetbread of culinary language. It carries on the work com- 

 menced by the saliva, saccharifying tho starch ; it seems also to 

 have on action on fatty matters. It is one of the few fluids in 

 the body which contain albumen in a soluble state. 



The "bile is secreted by the large and important gland, the 

 liver, from the venous blood ; it is collected in the gall-bladder, 

 from which it is passed by a duct into the digesting food. Its 

 colour is greenish-yellow, and from containing mucus it is ropy. 

 From the latter it may be separated by dissolving ia aloohoL 



It U found to bo a compound of nodi urn with two resinous Midi, 

 ylycnchfjlic and tawroehoUe, bat it i 

 pound, and in itn analysis there appear 

 stances. 



Cluilexterine is ever present in very small quantities, hot it U 

 extremely insoluble, and when onoe too much U secreted it 

 becomes deposited in the gall-bladder, forming "gall-stones;" 

 when these get into the duct, violent pains at onoe ensue. 



(2.) Blood is the great agent which builds op and repair* the 

 body, and furnishes material from which the gland* extract their 

 secretions. Hence it contains all the element* necessary to 

 renew every part of the frame. When allowed to stand it soon 

 coagulates; this is brought about by the fibrine refusing to 

 remain in a fluid state when separated from the action of life. 

 If this fibrine be removed, as previously described, the blood 

 will remain fluid. Under tho microscope it appears not M a 

 fluid of uniform colour, but as consisting of tenon, a yellowish 

 transparent liquid, in which float red 



Blood corpuscles. Those the fibrine as it coagulates gathers 

 together mechanically, and thus the blood is separated into its 

 two ports. These corpuscles owe their colour to haematine, which 

 contains no less than 6*6 per cent, of iron. This may be removed 

 without materially affecting the colour. 



The corpuscles are flattened discs, the shape of which varies 

 in different animals. 



Tho blood which flows back to the heart by the veins owes its 

 dark colour to the presence of carbonic acid gas ; whilst the 

 bright red of the arterial blood is due to the free oxygen which 

 it contains. The supposed process of respiration was alluded 

 to in the lesson on carbonic acid. 



The normal constitution of the blood is albumen, fibrine, 

 haematine, globuline; oleio, stearic, lactic, phosphoric, sulphuric, 

 and hydrochloric acids combined with sodium, potassium, am- 

 monium, calcium, and magnesium ; small portions of cholesterine 

 and phosphorised fat. 



Chyle. The intestines are lined with a set of vessels, termed 

 lacteals; these absorb from the digested food this incipient 

 blood, which is a milky fluid, and empty it into the thoracic duct, 

 from which it enters into the general circulation. 



Its composition, determined from the few specimens which 

 have been obtained, is similar to that of blood, and some few of 

 the red corpuscles are found in tho thoracic duct. The true 

 nature of chyle and blood is not well understood ; it may yet be 

 found that the red corpuscles are animal organism*. 



LESSONS IN LATIN. XL. 



DEVIATIONS IN THE THIBD CONJUGATION (continued) 

 4. Perfect in -Ivi ; Supine in -ITUH. 



THESE verbs in the perfect and supine really follow the fourth 

 onjugation, and so form a kind of hybrid conjugation, a com* 

 pound of the third and tho fourth. 



i. Cupio, cupere, cupivi, cupitum, to desire. 



ii. Peto, petere, petivi, petition, to strive after, aim at; at, 

 aliquo, to ask from, entreat. 



iii. Quaero, quserere, qurcsivi, qnsesitum, to seek. The com- 

 Dounds are in quiro, quisivi, quisitum ; as, exquiro, to March 

 out. 



iv. Kudo, rude'ro, rndivi and rndi, rnditnm, to nor. 



v. Tero, terere, trivi, tritum (E. B. trite), to rub. 



vi. Arcesso, arcessere, arcessivi, arcesaitum, to tend for. 



vii. Capesso, capesse're, capesaivi, capessitum, to take in Ktmi 



viii. Facesso, facesse're, faoessivi, facessitnm, to make, takt 

 yourself off; negotium faoessere, to give trouble. 



ix. Incesso, incessere, inceasivi (no supine), to fall upon. 



z. Locesso, lacessere, lacesaivi, lacessitum, to challenge. 



Adipiscor, adipisci, ' 



adeptus sum, dep., ' 



to obtain. 

 Aratrum, -i, n., a 



plough. 

 Attertre, to rub at, or 



wear down, 

 areo, cavi, cautum, 



to takt care, aroid. 

 Cupide, eagtrly. 



