819 



PYRAMID. 



PYROMETER. 



860 



consist of the cores of the ancient monuments or pedestals of the 

 statues of the kings. They are 23 ft. high, slope 64, and stand on a 

 layer of Nile mucL A ruined pyramid exists at El Kufa. At Thebes 

 are some small pyramids of sun-dried bricks, the central chambers of 

 which have vaulted roofs, supposed to be of the 16th century B.C. 

 One of these at the Drah-Aboo-Negger, not facing the cardinal 

 points, is entered by a passage leading to a chamber at the bottom 

 of which is a tablet representing the king Knentef IV. of the llth 

 dynasty, followed by four dogs with their names. It is to this 

 pyramid and the adjoining tombs that the Abbott papyrus refers. 

 [PAPYRUS.] 



The principal pyramids in Nubia are those of Beg e Rauie, about 

 17 X. lat., called by Cailliaud Assur, and Hoskins Begromi, which 

 lie in three groups arranged in a crescent shape, and are the sepulchres 

 of the monarchs of Meroe. They do not face the cardinal points, but 

 the propylaea which are united to the pyramids all face the east, and 

 the sepulchral chambers which are constructed in the masonry lie to 

 the west. The inner walls of the sepulchral temples are ornamented 

 with Osiria and other Egyptian deities, and the names and legends of 

 the monarchs for whom they were made, one of whom had assumed 

 the prsenoinen of Sesortesen I., but many of the names and inscriptions 

 cannot be deciphered. The art is of a late period, but the number of 

 kings show a long duration of empire. One of these pyramids had 

 been encased and enlarged at a later period, and in another, Ferlini, in 

 1834, found a collection of solid gold rings, a bronze vase and other 

 objects walled up. Another group of about one hundred and twenty 

 > lies at El Gues N. of Gebel Barkal, and at Nourri, 18 N. lat., 

 another group of about twenty-five, the graves of the ^Ethiopian 

 monarchs, whose capital was Mount Barkal, the ancient Napata, of 

 which Tahraka was the most renowned monarch. The largest pyramid 

 contains within it another of a different date, stone, and architecture. 

 The base is about 155 ft., and the height about 104 ft. Other groups 

 are at Tanqassi, Kurru, and Zuma. 



Buildings of this shape are not confined to the valley of the Nile : 

 the Birs Nimrud, of Belus, supposed to be the Tower of Babel, but 

 now known to be a temple built by Nebuchadnezzar to the Seven 

 Planets, in form of a step-shaped pyramid of different stages of 

 appropriately coloured bricks 235 ft. high, with a perimeter of 2286 ft. 

 The Mujellibe, also of pyramidal shape, is another edifice of brick- 

 work erected by the same monarch; it is 140 ft. high, 600 ft. on the 

 N., 657 on the 8., 546 on the E., and 558 ft. on the W. side, and has a 

 hollow shaft 60 ft. square. Xenophon, in his account of the retreat of 

 the 10,000, also mentions a stone pyramid which he saw near the 

 Tigris, about 45 miles S. of Mosul, about 200 ft. high. The tomb of 

 Bardanapalus, at Tarsus, also appears to have been of pyramidal shape, 

 and the mausoleum at Halicarnassus terminated in a step-shaped 

 pyramid of 24 steps, rising 42 ft. 6 in., surmounted by a colossal 

 quadriga. The idea seems borrowed from the Egyptians, with whom 

 the Carians entertained at an early period political relations. Similar 

 tombs, consisting of pyramids, supported on celUo and columns or 

 pilasters, have been found at Mylasa in Caria, at Oi'inin near Ben I/li in 

 J'hrygia, at Celenderis in Cilicia, and elsewhere. 



At Rome, within the walls of Aurelian, is a small pyramid 120 ft. 

 high, and 95 ft. diameter, of marble face, formed of hewn stone upon a 

 pavement of travertine, erected 20 or 30 years B.C. The door is on 

 the N. side, and inside is a small sepulchral chamber with obliterated 

 paintings on the walls and roof. It was erected in honour of 

 C. Cestius, one of the seven marshals, Epitlnna, who furnished the 

 banquets of the gods, according to the directions of his will by his 

 executor M. Agrippa. There is an inscription on the front and 

 back of the monument recording the name and title of the deceased, 

 and that the work was begun and ended by Pontius and Pothas 

 in 360 days the Roman lunar year. It is generally known 

 as the pyramid of Cestius, and was evidently imitated from the 

 Egyptian. 



There are some temples of pyramidal form at Benares, and other 

 places in the East Indies, which are said to be copies of the sacred 

 mount Mene, and are called Merit Sringat, or " Peaks of Meru." 

 Pyramidal structures called Leen tan, representing the mountain of 

 Yu, and used for sacrifice, exist at Pih-king, and have several stages 

 ascended by flights of steps. Pyramidal temples have also been found 

 at Suka in Java. 



The Mexican pyramids called Teoralla, meaning " House of God," 

 or " Temple," consist of pyramidal mounds of earth or stone, terraced, 

 and mounted by steps, having on them the statues or altar of the god 

 to whom they were dedicated, and where their bloody human sacrifices 

 were performed. [MEXICAN ARCHITECTURE.] 



Pyramidal structures called mora.it, of large size, are found in the 

 Polynesian islands : a stone one at Atehuru, 270 ft. long, 94 ft. broad 

 at base, and 50 ft. high, with a flat top reached by a flight of steps, the 

 lowest 6 ft. high ; the whole was cased with coral and basalt ; another 

 at Maeva was 120 ft. square. These structures were used as places of 

 worship and burial. Easter Isle abounds in these morals. Colossal 

 tatn'es were often erected on the summits. 



The pyramidal form in connection with sacred and sepulchral edifices 

 appears to be distributed all over the world, and is nothing more than 

 a geometrical mound ; the facility of forming it, and the grand sim- 

 plicity as well as the solidity and pleasing proportions of the figure, 



ARTS AKD SCI. DIV. VOL. VI. 



having caused it to be selected as best suited for primeval archi- 

 tecture. 



( Long, Egyptian, Antiquities, vol. ii. in the Library of Entertaining 

 Knmclfdije ; Description derEgypte,Antia l v,ite'3,vo\.-v.; Sir G. Wilkin- 

 son, Topography of Thebes, 8vo, Lond., 1835; Col. Howard Vyse, 

 Operations carried on at Giseh in 1837, vols. i., ii., & iii., 8vo, 1840-1842 ; 

 J. Gliddon, Otia jEyyptiaca, Lond., 1849, p. 20-51 ; R. Lepsius, Ueber 

 den Ban der Pyramiden, in the MonaUberichte der Akademic z Berlin, 

 1843, p. 177; K. J. Buusen, Egypfi Place, 8vo, Lond., 1824; R. 

 Lepsius, Sriefe aus jEgi/pten, 8vo, Berlin, 1852, p. 197-239 ; A. 

 Mariette, Rtr. Arch., 1860, p. 161 ; E. G. Squier, The Serpent Symbol, 

 8vo, New York, 1851, p. 72-106; also Jolowicz, Billiotheca ^Sgyptiaca, 

 p. 204 & foil.) 



PYREN (C, H 12 ?). A crystalline substance procured from gas-tar. 

 It is insoluble in water, but crystallises in small rhombic lamina; in 

 alcohol. It is insipid and inodorous, slightly soluble in alcohol and 

 in ether. It melts at about 350 Fahr., and concretes on cooling into a 

 crystalline mass. A stronger heat volatilises it without alteration. 

 Sulphuric acid carbonises it. It much resembles paranaphthalin. 



PYRIDINE (C 10 H 5 N). A volatile organic base found in bone-oil. 

 In its properties it greatly resembles picoline. It yields the following 

 derivatives : 



. C 1(I H 5 N, HCl + PtCl, 

 . C 10 H 3 Pt"N 

 . C 10 II,PtN 



Chloroplatinate of pyridine 

 Platinopyridine . . 

 Platosopyridinc . 

 Iodide of ethyl-pyridine . 



PYRITES. [METALS ; Iron, BUvlphate of.} 



PYROBENZOLIN. Synonymous with LOPHTNE. 



PYROCATECHIN. [PHENYLIC GROUP.] 



PYROCITRIC ACID. [CITRIC ACID.] 



PYROGALLIC ACID. (C, 2 H 8 B ). If the dry extract of nut galls 

 be heated to 356 Fahr. for 10 or 12 hours, a beautiful white crystal- 

 line substance sublimes, which is pyrogallic acid : 100 parts of the dry 

 extract yield about 5 parts of the sublimed acid. Pyrogallic acid is 

 Eoluble in 2J times its weight of cold water, and much less soluble in 

 alcohol and ether. It does not redden litmus paper. Rendered alka- 

 line with potash or soda, it rapidly absorbs oxygen, and assumes a 

 blood-red colour. It is employed in eudiometry for the estimation of 

 oxygen, and in photography for the development of collodion pictures. 



PYROGUAIACIC ACID. [GuAiACYL.J 



PYROINDLIN. [INULIN.] 



PYROLEIC ACID. [SEBACIC ACID.] 



PYROLICHENIN. A substance obtained from the Variolaria 

 amara. In order to procure it the powder of the lichen is to be treated 

 with alcohol, and the solution evaporated to the consistence of a syrup. 

 The pyrolichenin then crystallises, and after being washed with a 

 solution of carbonate of potash it is to be dissolved in and crystallised 

 from alcohol. 



Its properties are : It forms colourless inodorous crystals unalter- 

 able in the air, inodorous, and of a bitter taste. It fuses below 212, 

 and concretes on cooling. It is insoluble in cold water, and slightly 

 soluble in boiling water, and nothing is deposited from it on cooling. 

 It is very soluble in alcohol, ether, bisulphide of carbon, and oils, both 

 volatile and fixed. The alcoholic solution has an acid reaction, and, 

 like the solution in acetic acid, and also in concentrated sulphuric acid, 

 it is precipitated by water. It is not decomposed by the nitric, hydro- 

 chloric, or phosphoric acids. 



It combines with ammonia, and forms yellow brilliant crystals, 

 which effloresce in dry air. They are insipid, and dissolve readily in 

 alcohol and the caustic alkalies. Solution of potash dissolves pyro- 

 lichenin with a wine-red colour, which gradually becomes brown. Acids 

 precipitate from it a bitter reddish-brown substance. When decom- 

 posed by heat it yields no ammonia ; and when heated in the air it 

 burns with a bright sooty flame, which is violet-coloured on the edges. 

 Its composition is not known : it is stated to possess antifebrile pro- 

 perties. 



PYROLIGNEOUS ACID. [ACETIC ACID.] 



PYROLITHOFELLIC ACID. [LITHOFELLIC ACID.] 



PYROLIVILIC ACID. [OLIVILE.] 



PYROLIZARIC ACID. [NAPHTHALIC GROUP.] 



PYROMARIC ACID. [TURPENTINE.] 



PYROMECONIC ACID. [MECONIC ACID.] 



PYROMELLIC ACID (C^H.O,,). A crystalline organic acid, 

 obtained by distilling mellic acid : 



3C 8 H.,0. = 4CO, + C,.H.0 1B 

 Mellic acid. Carbonic acid. Pyromellic acid. 



PYROMETER (literally "fire-measurer," from irBp, "fire," and 

 UtTfov, " a measure "). No fluid has hitherto been found applicable to 

 the construction of thermometers capable of indicating higher tempe- 

 ratures than that of boiling mercury (about 660 Fahr.). The term 

 pyrometer was first employed by Muschenbroek to designate an instru- 

 ment invented by him for measuring the effects produced in the 

 dimensions of solid bodies by the application of heat; but the sign ifi- 



