RES 



'Whenever this function is suspended, 

 even for a very short time, the animal 

 die*. The fluid respired by animals is 

 common atmospherical air; and it has 

 been ascertained by experiment, that no 

 other gaseous body with which we are 

 acquainted can be substituted for it. All 

 the known gases have been tried ; but 

 they ail piv.'ve ratal to the animal which 

 is made to breathe them. Gaseous bo- 

 dies, a--, r'jr as respiration is concerned, 

 inuy uivid -d into two classes: 1. Un- 

 I'tspn ir gases. 2. Respirable gases. 

 : ues bt-lunging to the first class are 



of budb iuuiiit-, that they cannot be 

 into the lungs of an animal at all ; 

 the epiglottis closing spasmodically when- 

 ever they are applied to it. To this class 

 belong carbonic acid, and probably all 

 the oilier acid gases, as has been ascer- 

 tained by the experiments of Pilatre de 

 Jtozier, who went into a brewer's tub 

 iviiite full of carbonic acid gas evolved by 

 fermentation. A gentle heat manifested 

 itseif in all parts of his body, and occa- 

 sioned a sensible perspiration. A blight 

 itching sensation constrained him fre- 

 quently to shut his eyes. When he at- 

 tempted to breathe, a violent feeling of 

 {suffocation pr \ : sited him. He sought 

 for the steps to t ' tt out ; but not finding 

 them readily, the necessity of breathing 

 increased, he became giddy, and felt u 

 tingling sensation in his ears. As soon 

 as his mouth reached the air, he breathed 

 freely ; but for some time he could not 

 distinguish objects ; his face was purple, 

 his limbs weak, and he understood with 

 difficulty what was said to him. But 

 these symptoms soon left him. He re- 

 peated the experiment often ; and always 

 found, that as long as he continued with- 

 out breathing, he could speak and move 

 about without inconvenience; but when- 

 ever he attempted to breathe, the feeling 

 of suffocation came on. For the lungs of 

 animals suffocated by it were found by 

 Piiatre not to give a green colour to ve- 

 getable blues. The gases belonging to 

 the second class may be drawn into the 

 lungs, and thrown out again without any 

 opposition from the respiratory organs : 

 of course the animal is capable of respir- 

 ing them. They may be divided into 

 tour subordinate classes : 1. The first 

 set of gases occasion death immediately, 

 but produce no visible change in the 

 blood. They occasion the animal's death 

 merely by depriving him of air, in the 

 same way as he would be suffocated by 

 being kept under water. The only gases 

 which belong to this class are hydrogen 

 TOL. V. 



and azotic. 2. The second set of gases 

 occasion death immediately ; but at the 

 same time they produce certain changes 

 in the blood, and therefore kill, not mere- 

 ly by depriving the animal of air, but by 

 certain specific properties. The gases 

 belonging to this class are car bu retted 

 hydrogen, sulphuretted hydrogen, carbon- 

 ic oxide, and perhaps also nitrous gas. 3. 

 The third set of gases may be breathed 

 for some time without destroying the ani- 

 mal; but death ensues at last, provided 

 their action be long enough continued. 

 To this class belong the nitrous oxide 

 and oxygen gas. 4. The fourth set may 

 be breathed any length of time without 

 injuring the animal. Air is the only gase- 

 ous body belonging to this class. See 

 PHYSIOLOGY, and Thomson's Chemis* 

 try. 



RE5PONUEAS ouster, is to answer 

 over in an action to the merits of the 

 cause. As if a demurrer is joined upon 

 a plea to the jurisdiction, person, or writ, 

 and it be adjudged against the defendant, 

 it is a respoudcus ouster-. 



REST, the continuance of a body in the 

 same place, or its continual application or 

 contiguity to the same parts of the ambi- 

 ent or contiguous bodies ; and therefore 

 is opposed to motion. Sir Isaac Newton 

 defines true or absolute rest to be the 

 continuance of a body in the same part of 

 absolute space ; and relative rest to be 

 the continuance of a body in the same part 

 of relative space. Thus, in a ship under 

 sail, relative rest is the continuance of a 

 body in the same part of the ship ; but 

 absolute, is its continuance in the same 

 part of universal space in which the ship 

 itself is contained. It is one of the laws 

 of nature, that matter is indifferent to 

 motion or rest, as has been shown under 

 the article INERTIA. 



REST, in poetry, is a short pause of the 

 voice in reading, being the same with the 

 caesura, which, in Alexandrian verses, 

 falls on the sixth syllable ; but in verses 

 often or eleven syllables, on the fourth. 



RESTIO, in botany, a genus of the Dio- 

 ecia Triandria class and order. Natural 

 order of Calamarirc. Essential character: 

 calyx three-leaved, two of the leaflets 

 boat-shaped; corolla three-leaved, leaf, 

 lets lanceolate, one wider : female, germ 

 three-sided ; style one, seldom two or 

 three ; stigmas one, two, three, feathered. 

 There are twenty-eight species. These 

 plants are all natives of the Cape of Good 

 Hope, where some of them are used for 

 making ropes, for brooms, or for thatch- 

 ing. 



4D 





