TENDRIL. 124 TENEMENT HOUSE PROBLEM. surroundetl by a cortex of thin walled and some- what elongated parenchyma cells, covered by a delicate epidermis. (See Histology.) Physio- logically, they are sensitive to friction, often remarUably. Sensitiveness is ordinarily greatest on the concave side of the curved tip, though some tendrils are more sensitive on the Hanks and others equally sensitive on all sides. Ten- drils of Cyclanthera luider favorable conditions will respond to a stinuilus in less than ten sec- onds, those of Passitlora in about 30 seconds, ■while those of some other plants may only re- spond after 30 to 00 minutes. The response con- sists in a curvature of the tip. This is first due to the shortening of cells on the concave side and the lengthening of those on the convex side. This temporary curvature is maintained by the ac- celerated growth of the convex side, so that the part of the tip beyond the object with which it has come into contact is coiled around the sup- port, provided this be of sufficiently small diam- eter. If large and rough the tip may be ap- pressed to the surface, growing closely into the irregularities, and so adhere more or less firmly in that way. The petioles of some leaves, e.g. Clematis, show a similar but less acute sensi- TENDRILS OF BRYONY. a. a tendril that has attached itself and is coilingr, with reversal of coils in centre: fa. a recently attached tendril, the unequal firowth just bef^inning; c. one just attached; d. one just straightened out; e, one still coiled from the bud. tiveness to friction, making one turn about a support. Uncaria has short conical hooks which are stimulated by contact and friction 4o grow in such a way that they enlarge gieatly and curve about a support. After a tendril has laid hold of an approjiriate support the portion be- tween the support and the axis of the plant is brought under strain, to which it responds by unequal growth on one side. By this means it is thrown into a spiral with one or more points of reversal (a mechanical necessity when a once straight cylindrical body elongates on one side and so coils up). The coils develop mechanical tissues, and the most perfect tendril thus becomes a strong, uniformly coiled, elastic spiral spring which supports the plant. See Lianas. TENEBR.a! (Lat.. darkness). A service in the Roman Catholic Church ; the matins of Thursday, Friday, and Saturday in Holy Week, generally sung on the preceding evening. The name is taken from the opening of the Kespon- sorium following the fifth lesson on Good Fri- day, Teiicbrce factw sunt. The service consists of si.xteen Psalms and a Canticle from the Old Testament, sung with their proper Antiplions in fourteen divisions, nine Lessons, nine Respon- sories, the Canticle Benedictus, and the Miserere. Most of the service is in unisonous ])laiii chant. At the conclusion of each Psalm and Antiplion one of the fifteen candles in the triangular candle- stick used for this special service is extinguished with ceremony. During the singing of the Bene- dictus the six altar candles are put out one by one. The only light remaining is the candle at the apex of the candlestick. This is removed and carried liehind the altar. After the singing of the Antiphon, Christus factiis est pro nobis oredi- ens usque ad mortem, a silence follows, during which the Paternoster is whispered in secret; after the Miserere, a prayer is made and the candle is brought from behind the altar. Then, according to the rubric, "all rise and depart in silence." TEN'EDOS. An island in the .^gean Sea, situated five miles from the northwestern coast of Asia Jlinor, near the entrance of the Darda- nelles (Map: Greece, G 2). Area, 16 square miles. The only town which bears the name of the island is inclosed by walls and has. an old castle and remains of the storehouses erected by .Ju.stinian. The surface of the island is uneven and rocky, but the soil is fairly fer- tile. Wine is the most important product, about. 5.000.000 gallons being annually exported. Pop- ulation, about 4000, one-third of whom are Jlohammedans. Originally settled by .Eolians, Tenedos was successively under tlie control of Persia, Athens, Rome, the Byzantine emperors, and Venice. Since 1322 it has been a Turkish possession, and is included in the Archipelago- Vilayet. TENEMENT (Lat. tcitcuientum, a holding, fief, from trncre, to hold, retain). In the strict legal sense, anything of a permanent nature, corporeal or incorporeal, which may be lield or be an object of tenure (q.v.). The term is now used in a very broad sense and denotes any estate or interest in lands. The word is alsO' popularly used to denote a rented house, espe- cially one which is occupied by several fam- ilies. See Real Propebty. TENEMENT HOUSE PROBLEM. The problem of the making possible a healthful hu- man existence under the conditions of dense popu- lation in our modern cities. With the growth of great cities, a double movement of population- takes place. The well-to-do are driven from former residential districts by the encroachments of business, while working people crowd into their vacated houses. Rear tenements are built behind the old houses : new structures are put up solely for use as tenements ; and the whole- process is left in the hands of private builders- and landlords, ill-regulated by the municipality, until its two most obvious evils, the danger from epidemics and the danger from fire, force them- selves upon public attention. The fundamental evil of the tenement is crowd- ing under tinsanitary conditions. Houses built for one family cannot be adapted to hold four or more, sanitary conveniences become increas*
