769 



ELAENE. 



ELASTICITY. 



770 



would be capable of receiving the injury of dispossession. A lease for 

 years was therefore stated to have been made by the party claiming title 

 to the plaintiff, who was a fictitious person, John Doe. It was also stated 

 that the lessee, in consequence of the demise to him, entered into the 

 premises, and that the defendant, who was also a fictitious person, 

 Richard Roe, and called the casual ejector, entered thereupon and 

 ousted the plaintiff, for which ouster the plaintiff brought his action. 



A notice professing to be written by the casual ejector to the tenant 

 in possession of the premises, advised him to appear in court at a 

 certain time and defend his title; otherwise he, the casual ejector, 

 would suffer judgment to be had against him, by which means the 

 actual tenant would inevitably be turned out of possession. 



The declaration, in the action, formally stated the lease, entry, and 

 cutter, and it and the notice were then served upon the tenant in 

 possession of the premises, who had thus an opportunity of defending his 

 title. If he omitted to do so within a limited time, he was supposed 

 to have no right ; and upon judgment being obtained against the casual 

 ejector, the real occupier was turned out of possession by the sheriff. 



If the tenant applied to be made a defendant, he was allowed to 

 appear upon condition that he entered into a rule of court to confess 

 at the trial of the cause four of five requisites for the maintenance of 

 the plaintiff's action the lease of the lessor, the entry of the plaintiff, 

 the ouster by the tenant himself, and the possession by the tenant. 

 These requisites were wholly fictitious ; and if the plaintiff should put 

 the defendant to the proof of them, he would of course be nonsuited 

 at the trial ; but the stipulated confession of lease, entry, and ouster 

 being made, the case then rested upon the merits of the title only, 

 and the cause went to trial under the name of the fictitious lessee on 

 the demise of the lessor, who was the person really claiming title 

 against the defendant. 



The lessor was bound to make out on the trial his title to the 

 premises ; and if he did so in a satisfactory manner, judgment was 

 given for the nominal plaintiff, and a writ of possession went to the 

 sheriff to deliver up the possession to him, under which process it was 

 in fact delivered to the real claimant. If it appeared that the person 

 claiming title had no right of entry, that is, no right to the immediate 

 possession, he could not maintain his action. 



The Common Law Procedure Act, 1852, has abolished the fictions 

 above alluded to, by substituting for the declaration Doe v. Roe and 

 the notice by Roe to the tenant in possession, a single writ, directed 

 to the tenant in possession, in which the plaintiff asserts his right to the 

 property described in it. If the tenant, or his landlord who is entitled 

 to notice from the tenant, disputes the claimant's right, one or other 

 must appear and defend the action, the appearance being construed to 

 be a denial of the title of the claimant, on which the parties may 

 proceed to trial. If the tenant or his landlord does not appear, the 

 claimant obtains an ordinary judgment by default, on which the 

 sheriff gives him possession. 



A mortgagee may maintain an action of ejectment against the 

 mortgagor to gain possession of the mortgaged premises without 

 giving any notice, unless the mortgagor is protected by the covenant 

 for quiet enjoyment until default. He may also eject the lessee, to 

 whom the mortgagor has made a lease subsequent to the mortgage, 

 without giving him notice to quite. Where the right of the tenant to 

 retain the possession has ceased by effluxion of time, by a legal notice 

 to quit, or by the commission of an act of forfeiture, a landlord may 

 bring an ejectment against his tenant ; and various other persons who 

 have a right of entry in law upon the premises may take advantage of 

 the same remedy. 



The time within which an action of ejectment may now be brought 

 is regulated by the 3 & 4 Will. IV. c. 27, which enacts that no person 

 shall bring an action to recover any land or rent but within twenty 

 years next after his right to bring such action, or that of the person 

 through whom he claims, shall have first accrued. The third section 

 fixes the time at which the right shall be deemed to have first accrued. 

 (Blackstone's ' Commentaries,' Mr. KBIT'S edit., vol. iii. p. 206.) 



ELAENE. [NONYLE.NE.] 



EL.EOPTENS. [ESSENTIAL OILS.] 



HI. AfDIC ACID. [OLEIC Aero.] 



ELAlDINE, a fatty substance, of uncertain composition, produced 

 by the notion of nitrous acid upon certain oils, as olive and almond 

 oil, &c. This substance is white, inodorous, insoluble in water, and 

 fusible at 95 Fahr. It is soluble in ether, and in 200 times its weight 

 of boiling alcohol ; when treated with potash it saponifies, giving rise 

 to glycerin, and a peculiar acid which has been called elaidic acid. 

 This acid is solid, fusible at 112 Fahr., and is partially distilled by ex- 

 posure to a strong heat. [OLEIC ACID.] 



ELAIODIC ACID. [RiciNOLic ACID.] 



ELALDEHYD. When aldehyd is kept for some tune in sealed 

 tubes, it is converted into two polymeric bodies, metaldehyd, a hard 

 crystalline inodorous solid, and daldehyd, which is a liquid. [OTHYL, 

 HVDKIDK OP.] 



ELASTICITY. When the form of a body is affected by the pres- 

 sure of another extraneous to it, the re-acting force by which . it 

 sustains or tends to remove that pressure is its elasticity. This energy 

 of restitution is thus defined by D'Alembert : " La force elastique est 

 une proprie'te' ou puissance des corps, au moyen de laquelle ils se 

 rcitablissent dans la figure et IMtendue, qu'une cause exte"rieure leur 



ABT3 AND SCI. DIV. VOL. III. 



avait fait perdre." The term has been very loosely used in popular 

 works, which, instead of furnishing an exact and general idea of this 

 force, are, in general, limited to the phenomena exhibited by elastic 

 solid bodies ; and to this imperfect notion of elastic force we are to 

 attribute the discrepancies of treatises, some 'of which used to repre- 

 sent water as perfectly inelastic, some (as the more modern treatises) 

 as perfectly elastic. The cause of elasticity then belongs to the theory 

 of molecularity, its effects in aggregate masses to mechanics. 



The equilibrium of the molecules of solid bodies is almost completely 

 dependent on their own mutual actions and quantity of heat. These 

 forces determine certain mean places for the constituent particles, to 

 which points of stable equilibrium they tend to return when removed 

 a little from them by an external force. This removal may be such 

 as to effect in the mass either compression or extension, inflexion, or 

 torsion, and therefore their elastic force is capable of being exhibited in 

 all these ways. It is demonstrated in fluids only by their compressi- 

 bility, while in gases it acts as a predominant living force which 

 would refuse any position of equilibrium to the constituent particles 

 without external pressure, and is proportional to such pressure uni- 

 formly exercised. 



When heat is applied to a solid elastic body, that is, when its 

 temperature is raised, the particles seek a different position of equili- 

 brium more remote from each other than before. But while this heat 

 is much below that necessary for friction, or for destroying the fibrous 

 formation of organized matter, the stability of the removable particles 

 is but little affected, and experiment shows that there is scarcely any 

 change of elasticity. In fluids the compressibility obtains a greater 

 range, while in gases, where no countervailing force of attraction ig 

 sensible, the increase of temperature is accompanied by a proportional 

 increase of elastic force. 



Amongst bodies whose elasticity is very apparent, we may enume- 

 rate glass, ivory, caoutchouc, sponges, and fibrous substances, as beams, 

 muscles, and artificial webs, some gums, steel, and all the gases and 

 vapours. In gases and vapours its effects may be produced to any 

 extent, but they are limited in solids by their softness and facility of 

 fusion, as in wax, lead, &c. ; by their absorption of moisture, as in 

 clay, feathers, catgut, straw ; or by their friability, as in glass, dry 

 resins, and copper or iron which have been exposed to a stream of 

 ammoniacal gas. 



Suppose an elastic string, or lamina, to be fixed at one end, and at 

 the other stretched by a force T, which will also represent its tension; 

 if this force be increased by a small quantity (, an additional length I 

 would be given to the string, or lamina ; the whole tension now ia 

 T + t, and if we again add a force t, since the physical condition of the 

 body is sensibly the same as before, the same length I will again be 

 added, and generally the additional extension should be proportional 

 to the additional tension : this law is, however, only approximative, for 

 it is manifest that a force tending to produce either extension or con- 

 traction may be applied which would cause the body to break, aud 

 near these limits the law would vary considerably from simple pro- 

 portionality. Let a horizontal elastic lamina A B be fixed by a screw 

 at A, and having been stretched by a known weight G at B let it be 



screwed also at that point, when its tension will evidently be equal to 

 the weight appended ; let the beam D E of a balance F be sustained at 

 D, the middle of A B through a drilled orifice d, and be attached to a 

 string passing over the fixed pulley c, which string also sustains a 

 weight P, which is an exact counterpoise to the weight of the scale and 

 beam so that they may produce no deflection of themselves in A B ; 

 then if a small weight be put into the scale, the lamina A D B will be 

 bent into the form A d B, with a dellection D d from its original 



3D 



