TEN 



189 



T E N 



w' lh the intention of thus defending the main ditch; and 

 in order that the defenders of the tenaille may not be 

 injured by the shot fired over their heads, from the flanks 

 of the bastions, it is usual to make the crest of that work 



coincid 

 below 



;ide with a horizontal plane passing three or 

 rV the point where a line of fire from one 



four feet 

 of those 



flanks would cut a vertical plane, bisecting the angle of 

 the tenaille or its curtain. The height thus determined 

 will allow the parapet of the work to be elevated from 

 two to four feet above the terreplein of the ravelin in its 

 front; and, consequently, from the curtain of the tenaille 

 a grazing fire of musketry might be employed to protect 

 the interior of the ravelin, or of its reduit, if there is one, 

 should the defenders of either of those works abandon it 

 (in consequence of an assault being made) before the 

 enemy lias time to cover himself in it by a lodgment : that 

 fire will also contribute powerfully to prevent the enemy 

 from attempting to enter the ravelin by its gorge. 



Vanban, at first, gave to his tenailles short flanks nearly 



' ram's horns ' was given, has seldom been put in prac- 

 tice. 



Any work belonging either to permanent or field for 

 tification, which, on the plan, consists of a succession of 

 lines forming salient and re-entering angles alternately, is 

 said to be d tenaille. 



TENAILLON, or Great Tenaille, in Fortification, is a 

 species of exterior work which has been occasionally con- 

 structed before the faces of a small ravelin, with a view of 

 increasing the strength of the latter, procuring additional 

 space beyond the ditch, or covering the shoulders of the 

 bastions. They were invented by Vauban, who, however, 

 very seldom constructed them ; and subsequent engineers 

 have generally considered them as inferior in defensive 

 qualities to a counterguard [QQ, FORTIFICATION', Fig., p. 

 377] placed over the faces and salient angle of the 

 ravelin. 



The form and position of a tenaillon may be 'understood, 

 Y being supposed to represent a small ravelin, if beyond 



parallel to those of the bastions, but he soon abandoned the ditch of the latter the ramparts of the right and left 

 that construction, perceiving that though the defenders faces be produced till each of them meets a rampart 

 might thus fire correctly along the main ditch, yet the nearly perpendicular to the face of the bastion and ex- 

 parapets of those flanks were liable to be destroyed by the ! tending to the place of meeting from the counterscarp of 

 fire from the enemy's counter-batteries [H, Fig. 1, BAS- ' the main ditch at a point opposite the middle of that face. 

 TIO.V], and they were enfiladed from the rampart of the | The works thus formed, one over each lace of the ravelin 



ravelin (Q), or from the glacis of the places of arms (L). 



Besides affording additional fires for the defence of the 

 main ditch, the tenaille serves to cover, in part, the revet- 

 ment of the curtain in its rear, and prevent it from being 



Y, constitute a tenaillon ; before each line of rampart is 

 a ditch, and part of the general covered-way, the main 

 ditch and that of the ravelin being in the rear. The two 

 laces which are beyond the salient angle of the ravelin 



breached bv fire from any lodgments of the enemy on the would, if produced towards the latter, form with each 



I ' T. 1 lit j ' 1 1 it I*. 1_ 1- - 11 



glacis. Its parapet serves also to mask the postern in the 

 curtain of the enceinte, which would otherwise be so much 

 exposed to the fires from the counter-batteries, that the 

 defenders might be unable to communicate through it 



other a re-entering angle, whose vertex would coincide 

 with that of the said angle. 



The objections to tenaillons are.'that the besieger would 

 experience little difficulty in establishing a lodgment on 



with the outworks. On this account the breadth of the that part of the covered-way or glacis which is imme- 

 ditch between the curtain of the tenaille and that of the ! diately in front of the salient angle of the ravelin ; and in 

 enceinte is made such only as to allow the parapet of the this situation he would be able to breach the faces of the 



former, with the relief determined as above mentioned, to 

 conceal the postern from the view of the enemy on the 

 g!:u-is. This ditch is advantageous in preventing the de- 

 fenders of the tenaille from being injured by the splinters 

 which may be detached from the flanks and curtain be- 

 hind it ; and, when dry, it serves to cover bodies of troops 



-_ 1 ! I. ' , . I I 1 L _ 1_ Al. _ 1 ' 1 



two half-bastions in four places, by fires of artillery directed 

 along the ditches of the ravelin and those on the side 

 fare;, of the tenaillon. The salient angles of the tenaillon, 

 and of the ravelin which it covers, may be breached at the 

 same time, and, when the ditches are dry, it would be 

 possible to attack and cany the ravelin at the time of 



which may issue from thence and attack the enemy while { making the assaults on the tenaillon: then, the enemy 

 _ r the main ditch, prc\iously to making an assault, having trot possession of the former work, any retrench- 

 Il'thc main ditch contains water, the tenaille serves to ments which may have been made in the tenaillon must 



lie serves to 



t the boats and rafts by which the defenders of the 

 enceinte communicate with the outworks. 



The tenaille has been considerably improved by Bous- 

 mard, who, returning, in one respect, to the original idea 

 of \auban, has given flanks to the work in order that 

 the main ditch may be directly defended by them. These 

 flanks are raised high enough to cover the revetments of 

 the flanks of the bastions, while their upper surfaces may 

 azcd by a fire of artillery from thence ; and, instead 



necessarily be abandoned by the defenders. 



At the siege of Lille, in 1708, one of the tenaillons 

 held out a long time, but this is ascribed by French 

 engineers rather to the faulty manner in which the siege 

 was conducted by the allies than to the strength of the 

 work. 



The re-entering space between the two faces which are 

 in the prolongation of the faces of the ravelin, and which 

 constitute the head of the tenaillon, is sometimes occu- 



of bcirii: formed with open terrcpleins, and parapets for j pied by a small redoubt, consisting of two ramparts per- 



musketry, as usual, each flank of the tenaille is provided 

 with casemates, or vaults, for four pieces of artillery which 

 are placed nearly on a level with the terreplein of the 

 covered-way. These guns are consequently capable of 

 being directed against the counter-batteries (H) of the 

 enemy, as well as of defending the foot of a breach in the 



:ion. 

 This construction was adopted by Chasseloup de Laubat 



pendicular to the faces which have been just mentioned ; 

 and thus there may be obtained a good crossing fire for 

 the defence of that part of the covered-way which is con- 

 cealed by the salient angles of the tenaillons from the 

 defenders of the bastions. 



Demi-tenaillons are works placed also on the sides of a 

 ravelin, and consisting of two ramparts which are per- 

 pendicular to and nearly opposite the middle of the faces 



in the tenailles of the detached works which he executed I of the bastions and ravelins: these are usually accom- 

 about Alessandria, in Italy, when Napoleon (after the 

 battle of Marencn. proposed to make that, city the base 

 of his operations beyond the Alps. But, in order to avoid 

 the mischief which results from a fire directed against 

 .nates (the shot in striking the cheeks or sides of the 

 emir, ' Hi them splinters, which being 



vault do more injury to the defenders than 



the >-hot itself), this engineer raised before each flank of 

 the tenaille a mas.-, of earth which was reveted with brick- 

 work, and perforated in such directions that, in defending 

 1he ditch, the shot, from the casemates could be fired 

 through the apertures, v,hile the mass served as a mask 

 t the enemy from seeing the cmbra- 

 he flanks of the tenaille. 



Belidor, in his 'Science des Ingenieurs' (1729), proposed 

 in the form of a circular arc, 



panied by eounterguards which cover the salient angles 

 of the latter works, and are called Bonnets. 



TENANCY. [TENANT.] 



TENANT. [TENURE.] Tenants, in the more extended 

 legal sense of the word, are of various kinds, distinguished 

 from each other by the nature of their estates ; such as 

 tenants in fee simple, in fee tail, for life, &c. [ESTATE; 

 TENANT IN FEE SIMPLE, &c.] 



TKNANT AND LANDLORD. The word tenant in the 

 more limited legal sense, which is also the popular sense, 

 is i>ne uho holds land under another, to whom he is bound 

 to pay rent, and who is called his landlord. The present 

 article is confined to this sense of the word, in which it is 

 proposed to show the nature, construction, and effect oft he 

 conn-act by which the relation of landlord and tenant is 

 c(l; the rights, liabilities, and duties of each under it; 



Main and the shoulder o 1 ' it ceases or may be terminated ; and the legal means 



bastion. But this construction, to which the name of by which the rights and duties of each may be enforced. 



