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ORCHESTRION, a name applied to three different kinds of instruments, (1) A chamber organ, designed by Abt. Vogler at the end oi the i8th century, which in a space of 9 cub. ft. contained no less than 900 pipes, 3 manuals of 63 keys each and 39 pedals (see Harmonium). (2) A pianoforte with organ pipes attached, invented by Thomas Anton Kunz of Prague in 1791. This orchestrion comprised two manuals of 65 keys and 25 pedals, all of which could be used either independently or coupled. There were 21 stops, 230 strings and 360 pipes which produced 105 different combinations. The bellows were worked either by hand or by machinery. (3) A mechanical instrument, automatically played by means of revolving cylinders, invented in 1851 by F. T. Kaufmann of Dresden. It comprises a complete wind orchestra, with the addition of kettle-drums, side-drums, cymbals and triangle.  (K. S.) 

ORCHHA, or Urchha (also called Tehri or Tikamgarh), a native state of Central India, in the Bundelkhand agency. Orchha is the oldest and highest in rank of all the Bundela principalities, and was the only one not held in subjection by the peshwa. Area, 2080 sq. m.; pop. (1901) 321,634; estimated revenue, £47,000; no tribute. The maharaja, Sir Pratap Singh, G. S.C.I, (born in 1854, succeeded in 1874), took a great personal interest in the development of his state, and himself designed most of the engineering and irrigation works that have been executed here within recent years. He bears the hereditary title of “First of the Princes of Bundelkhand.” The state exports grain, ghi, and cotton cloth, but trade suffers from imperfect communications. The town of Orchha, the former capital, is on the river Betwa, not far from Jhansi. It possesses an imposing fort, dating mainly from the early 17th century. This contains a number of palaces and other buildings connected one with another. The most noteworthy are the Rajmandir, a massive square erection of which the exterior is almost absolutely plain; and the Jahangirmahal, of the same form but far more ornate, a singularly beautiful specimen of Hindu domestic architecture. Elsewhere about the town are line temples and tombs, among which may be noticed the Chaturbhuj temple on its vast platform of stone. The town of Tehri or Tikamgarh, where the chief now resides, is about 40 m. S. of Orchha; pop. (1901) 14,050. It contains the fort of Tikamgarh, by which name the town is generally called, to distinguish it from Tehri in the Himalayas.

ORCHIDS. The word Orchis is used in a special sense to denote a particular genus of the Orchid family (Orchidaceae); very frequently, also, it is employed in a more general way to indicate any member of that large and very interesting group. It will be convenient here to use the word Orchis as applying to that particular genus which gives its name to the order or family, and to employ the term “orchid” in the less precise sense.

The flowers of all orchids, though extremely diverse within certain limits, and although superficially very different from those of other monocotyledons, are all formed upon one common plan, which is only a modification of that observable in such flowers as those of the narcissus or snowdrop {Galanlhiis). The conformation of those flowers consists essentially in the presence of a six-parted perianth, the three outer segments of which correspond to a calyx, the three inner ones to a corolla. These segments spring apparently from the top of the ovary — the real explanation, however, being that the end of the flower-stalk or "thalamus, " as it grows, becomes dilated into a sort of cup or tube enclosing and indeed closely adhering to the ovary, so that the latter organ appears to be beneath the perianth instead of above it as in a lily, an appearance which has given origin to the term " inferior ovary." Within the perianth, and springing

A. Floral diagram of typical orchid flower; /, labeflum; a, anther; s, rudiments of barren stamens (staminodes).

B. Diagram of the symmetrical trimerous flower of Fritillary (Fritillaria).

from its sides, or apparently from the top of the ovary, are six stamens whose anthers contain pulverulent pollen-grains. These stamens encircle a style which is the upward continuation of the ovary, and which shows at its free end traces of the three originally separate but now blended carpels of which the ovary consists. An orchid flower has an inferior ovary like that just

Fig. 2. — Diagram of the flower of Orchis.

s, si, si, The three divisions of the outer perianth.

pi, pi, The two lateral divisions of the inner perianth.

ps, The superior division or the labellum, which may become inferior by the twisting of the ovary.

e. The fertile stamen, with its two pollen-masses in the anther-lobes.

r, The one-celled ovary cut transversely, having three parietal placentas.

Fig. 3. — Flower of Orchis.

s, s, s, The three outer divisions of the perianth.

p, p, l, The three inner, l being the labellum, here inferior by the twisting of the ovary.

e, Spur of the labellum.

o, The twisted ovary.

St, The stigma.

a. The anther, containing pollen-masses.

described, but with the ovules on the walls of the cavity (not in its axis or centre), a six-parted perianth, a stamen or stamens and stigmas. The main distinguishing features consist in the fact that one of the inner pieces of the perianth becomes in course of its growth much larger than the rest, and usually different in colour, texture and form. So different is it that it receives a distinct name, that of the " lip " or " labellum." In place of the six stamens we commonly find but one (two in Cypripedium), and that one is raised together with the stigmatic surfaces on an elongation of the floral axis known as the "column." Moreover, the pollen, instead of consisting of separate cells or grains, consists of cells aggregated into "pollen-masses, " the number varying in different genera, but very generally two, four, or eight, and in many of the genera provided at the base with a strap-shaped stalk or " caudicle " ending in a flattish gland or "viscid disk" like a boy's sucker. In Cypripedium all three stigmas arc functional, but in the great majority of orchids only the lateral pair form receptive surfaces {st, fig. 3), the third being sterile and forming the rostellum which plays an important part in the process of pollination, often forming a peculiar pouch-like process (fig. 4, r) in which the viscid disk of the pollen-masses is concealed till released in the manner presently to be mentioned. It would appear, then, that the orchid flower differs from the more general monocotyledonous type in the irregularity of the perianth, in the suppression of five out of six stamens, and in the union of the one stamen and the stigmas. In addition to these modifications, which are common to nearly all orchids, there are others generally but not so universally met with; among them is the displacement of the flower arising from the twisting of the inferior ovary, in consequence of which the flower is so completely turned round that the " lip, " which originates in that part of the flower, I conventionally called the posterior or superior part, or that

Fig. 4. — Diagram illustrating arrangement of parts in flower of Orchis. s. Sepals. p. Petals. a. Anther.

st, Two united stigmas. r, Rostellum (barren stigma).