a thousand feet lower. A detailed description of the volcano was published by the Mexican geological survey in 1895 according to which the crater is elliptical in form, 2008 by 1312 ft., and has a depth of 1657 ft. below the summit of the highest pinnacle and 673 ft. below the lowest part of the rim, which is very irregular in height. The steep, ragged walls of the crater show a great variety of colours, intensified by the light from the deep blue sky above. Huge patches of sulphur, some still smouldering, are everywhere visible, intermingled with the white streaks of snow and ice that fill the crevices and cover the ledges of the black rocks. The water from the melted snow forms a small lake at the bottom of the crater, from which it filters through fissures to the heated rocks below and thence escapes as steam or through other fissures to the mineral springs at the mountain's base. The Indian sulphur miners go down by means of ladders, or are lowered by rope and windlass, and the mineral is sent down the mountain side in a chute 2000 to 3000 ft. Some observers report that steam is to be seen rising from fissures in the bottom of the crater, and all are united in speaking of the fumes of burning sulphur that rise from its depths. That volcanic influences are still present may be inferred from the circumstance that the snow cap on Popocatepetl disappeared just before the remarkable series of earthquakes that shook the whole of central Mexico on the 30th and 31st of July 1909.
It is believed that Diego de Ordaz was the first European to reach the summit of Popocatepetl, though no proof of this remains further than that Cortés sent a party of ten men in 1519 to ascend a burning mountain. In 1522 Francisco Montaño made the ascent and had himself let down into the crater a depth of 400 or 500 ft. No second ascent is recorded until April and November 1827 (see Brantz Mayer, Mexico, vol. ii.). Other ascents were made in 1834, 1848 and subsequent years, members of the Mexican geological survey spending two days on the summit in 1895.
POPPER, DAVID (1846–), Bohemian violoncellist, was born at Prague, and educated musically at the conservatorium there, adopting the cello as his professional instrument. He was soon recognized, largely through von Bülow, as one of the finest soloists of the time, and played on tours throughout the European capitals. In 1872 he married the pianist Sophi Menter, from whom he was separated in 1886. In 1896 he became professor at the Royal Conservatoire at Budapest. He published various works, mainly compositions for the 'cello, together with four volumes of studies arranged as a violoncello school.
POPPO, ERNST FRIEDRICH (1794–1866), German classical scholar and schoolmaster, was born at Guben in Brandenburg on the 13th of August, 1794. In 1818 he was appointed director of the gymnasium at Frankfort-on-the-Oder, where he died on the 6th of November 1866, having resigned his post three years before. Poppo was an extremely successful teacher and organizer, and in a few years doubled the number of pupils at the gymnasium. He is chiefly known, however, for his exhaustive and complete edition of Thucydides in four parts (11 vols., 1821-1840), containing (i.) prolegomena on Thucydides as an historian and on his language and style (Eng. trans. by G. Burges, 1837), accompanied by historical and geographical essays; (ii.) text with scholia and critical notes; (iii.) commentary on the text and scholia; (iv.) indices and appendices. For the ordinary student a smaller edition (1843–1851) was prepared, revised after the author's death by J. M. Stahl (1875–1889).
See R. Schwarze in Allgemeine deutsche Biographie and authorities there referred to.
POPPY, in botany, a genus of plants known botanically as papaver, the type of the family or natural order Papaveraceae. They are annual and perennial erect herbs containing a milky juice, with lobed or cut leaves and generally long-stalked regular showy flowers, which are nodding in the bud stage. The sepals, very rarely three, which are two in number, fall off as the flower opens, the four (very rarely five or six) petals, which are crumpled in the bud stage, also fall readily. The numerous stamens surround the ovary, which is composed of 4 to 16 carpels and is surmounted by a flat or convex rayed disk bearing the stigmas. The ovary is incompletely divided into many chambers by the ingrowth of the placentas which bear numerous ovules and form in the fruit a many-seeded short capsule opening by small valves below the upper edge. The valves are hydroscopic, responding to increase in the amount of moisture in the atmosphere by closing the apertures. In dry weather the valves open, and the small seeds are ejected through the pores when the capsule is shaken by the wind on its long still slender stalk; The flowers contain no honey and are visited by pollen-seeking insects, which alight on the broad stigmatic surface. The genus contains about 40 species, mostly natives of central and south Europe and temperate Asia. Five species are British; P. Rhoeas is the common scarlet poppy found in cornfields and waste places. Cultivated forms of this, with exquisite shades of colour and without any blotch at the base of the petals, are known as Shirley poppies. P. somniferum, the opium poppy, with large white or blue-purple flowers, is widely cultivated (see Opium). The Oriental poppy (P. orientale) and its several varieties are fine garden plants, having huge bright crimson flowers with black blotches at the base. Many hybrid forms of varying shades of colour have been raised of late years. The Iceland poppy (P. undicaule), is one of the showiest species, having grey-green pinnate leaves and flowers varying in colour from pure white to deep orange-yellow, orange-scarlet, &c. Specially fine varieties with stalks 18–24 in. high are cultivated on a large scale by some growers for market. The Welsh poppy belongs to an allied genus, Meconopsis; it is a perennial herb with a yellow juice and pale yellow poppy-like flowers. It is native in the south-west and north of England, and in Wales; also in Ireland. The prickly poppy (Argemone grandiflora) is a fine Mexican perennial with large white flowers.
To the same family belongs the horned poppy, Glaucium luteum, found in sandy sea-shores and characterized by the waxy bloom of its leaves and large golden-yellow short-stalked flowers. Another member of the family is Eschscholtzia californica, a native of western North America, and well-known in gardens, with orange-coloured flowers and a long two-valved fruit pod.
The plume poppy (Bocconia cordate and B. microcarpa) are ornamental foliage plants of great beauty. The cyclamen poppy (Eomecon chionantha) is a pretty Chinese perennial, having roundish slightly lobed leaves and pure white flowers about 2 in. across. The tree poppy (Dendromecon rigidum) is a Californian shrub about 3 ft. high, having golden-yellow flowers about 2 in. across. The Californian poppy (Platystemon californicus) is a pretty annual about a foot high, having yellow flowers with 3 sepals and 6 petals; and the white bush poppy (Romneya Coulteri) is a very attractive perennial and semi-shrubby plant 2–8 ft. high, with pinnatifid leaves and large sweet scented white flowers often 6 in. across.
POPPY HEADS, a term, in architecture, given to the finials or other ornaments which terminate the tops of bench ends, either to pews or stalls. They are sometimes small human heads, sometimes richly carved images, knots of foliages or finials, and sometimes fleurs-de-lis simply cutout of the thickness of the bench end and chambered. The term is probably derived from the French poupée, doll, puppet, used also in this sense, or from the flower, from a resemblance in shape.
POPPY OIL (Oleum papaveris), a vegetable oil obtained by pressure from the minute seeds of the garden, or opium poppy, Papaver somniferum. The white-seeded and black-seeded varieties are both used for oil-pressing; but, when the production of oil is the principal object of the culture, the black seed is usually preferred. The qualities of the oil yielded by both varieties and the proportion they contain (from 50 to 60%) are the same. By cold pressing seeds of fine quality yield from 30 to 40% of virgin or white oil (huile blanche), a transparent limpid fluid with a slight yellowish tinge, bland and pleasant to taste, and with almost no perceptible smell. On second pressure with the aid of heat an additional 20 to 25% of inferior oil (huile de fabrique or huile russe) is obtained, reddish in colour, possessed