COLUMBIX. 



COLUMN. 



nan place* of Intenneat ha* ariam from the rr*etnblanee between 

 null arched bole* which oooUln Uw sepulchral urn* and the 

 nvtmut fi.nn.il f..r the dove* iu doreeote. 



ThU application of th word columbarium it proved by undent 

 fakMriptiona, but we ara not aware that the term U wed in this MOM 

 by any extant Latin writer. 



In the Villa Doria Pamnli at Rome WM diaoorered, in 1833, a very 

 extensive ooluml*rium. or rather an asmrniblage of columbaria, *jU*i 

 are ahown on the accompanying plan. It WM lurrounded by a wall, 

 with a triple entrance, formed by two column.. Tin. coluniKiria, 

 which are on a very diminutive wale, are pi I \.iilioutauyrcgu 

 larity. One building. A, superior in workmanship to the othon, 

 appeal* to hare been a mall temple in antin, built with red bricks, *et 

 with very delieate joinU, and rubbed on the surface*. The chamber*, 

 B, B. ,*<.-., were luperior cohunbaria, with largu niches, which .mi 

 tained double olhe or va** for the aahm of the dead, with small 

 tablet* let into the wall below each niche. The email structure* at c, c, 

 which mart reaetnble the dovecote*, are supposed to hnvc been the 

 sepulchre* of the slave*. They art built with reticulated work, and 

 are filled with sever*! row* of pigeon-holes, which contain olloo : they 

 have no inscriptions. The brickwork of these columbaria is of several 

 dates, if we may judge from the diversity of construction. The 

 chamber* B ft, B ft, have stone doorway*, Egyptian in character. The 

 interior of these little structures, and the temple, have been stuc- 

 coed and ornamented with reliefs, and painted. In the columbaria 

 of wealthy families a considerable amount of .l.-.-..r.i<i..u was some- 

 time* expended. In the immediate neighbourhood of the Columba- 

 rium, in the Villa Dona Pamfili, are numerous inscriptions, tablets, and 

 monumental unis. which belonged to these sepulchre.*, but having been 

 removed from the olke, they lose port of their interest. There ore 

 several columbaria in the neighbourhood of Rome, among which that 

 of the family Fompeia U remarkable for it* tablets and urns. There U 

 another and very fine sepulchral chamber, discovered in the year 1740, 

 near the gate of Kan Sebastian at Rome. 



COLUMBIX (C n H,,O,1), the Buppoeed active principle of the Co- 

 lumba root. The root contains, according to Buchuer 



Bitter subnUnce with resin 

 Rrnlnous colouring nutter 

 Wax .... 

 Gum .... 

 Starch .... 

 Pectin 



Fibre .... 

 Water, salts, and loss . 



. 12-2 



5-0 



2 

 4-7 



. 25-0 

 17-1 



. 22-6 

 12-9 



100 



Columbia is obtained from the alcoholic extract of the root, and 

 crystallises therefrom during spontaneous evaporation. It is purified 

 by filtering its alcoholic solution through animal charcoal, and it then 

 possesses the following properties : It crystallise* in bitter, inodorous, 

 e. -I. .urle*s rhombic prisms, possessing neither acid nor alkaline i 

 Batting alcohol of -835 dissolves from , to J of its weight. It is also 

 soluble in caustic alkalies. Taken internally it is poisonous. 



("U'MHirM (Ta) Tantalum. A metal found in 1802, in two 

 Swedish minerals, tanlalile and yttro-tantalite. The first, somtimex 

 called also Columiile, occurs amorphous and nodular, and also crystal- 

 lised in the form of a right rhombic prism. The massive variety is 

 cither granular or conijiact : the crystals are grayish-block : fracture 

 uneven; hardness, 6: sp. gr., G'038 ; lustre, imperfect metallic; it is 

 oji|iie. It contains about 80 per cent, of oxide of coluinbium, 12 of 

 oxide nf iron, mid 8 of oxide of manganese. The yttro-tantolito con- 

 tains oxide of columbium, yttria, ami some other substances. 



Cvlamblum is obtained with great difficulty. BerzcUus procured it 

 bv heating potassium with the potaaso-fluoridc of eolumbium. It is. a 

 black |M,wdcr, which by the burnisher acquires the colour and lustre 

 i.f iron. The specific gravity is about 6. It is nearly insoluble in 

 acid*. When heated in the air it- is oxidised, and converted into 

 columbic ncid. 



Oxygm and C<Jmbiam combine in two proportions, forming colum- 

 bjc acid and oxide of columbinm. 



(Mum/fie aeid may be obtaim .1 by burning the metal in the air ; it 

 scoIourlesK, insipid, nnd does not act upon vegetable blue colours. 

 When heated with ch.ircoal it i* reduced to the state of oxide. If 

 heated with iron it low* oxygen, and on alloy of iron and columbium 

 i formed. Columbic acid combined with water forms a very white 

 hydrate, which redden* vegetable blues. It combine* with snlifiable 

 base* to form salt* which are called columbatrt, but no one of them is 

 of any importance, or applied to any purpose what. 



tWdi/iiic arid i* composed of 



3 equivalent* of oxygen . . . 24 

 1 equivalent of columbium . . 185 



Equivalent . . 209 



Ofide ofC'-li'inltlum in obtained by heating columbic acid to white- 

 nea* in covered crucible. It i* of a graj ih black colour, very hard, 

 and almost infusible. 



Oxide of eolumbium coiuist* of 



2 equivalent* of oxygen . . . 10 

 1 equivalent of columbium . . 1 85 



Equivalent . . 201 



Columbium combine* al*o with chlorine and sulphur, 4e., but 

 com]x>unds are little known and of no importr 



< U.UMN, from the Latin rofonuta. The column i* a shaft of wood, 

 stone, or iron, in the form of a truncated cone, a little swelled from the 

 straight lino at about one-third it* height from the lower extremity : 

 this swelling U called the entaau. The column i* furnished with a 

 bate at the foot and a capital at the head of the shaft. Column* are 

 of variou* proportions ami kind* : circular on U plan, and rarely 

 polygonal. The Romans had five model* of column*, which were 

 called orders ; but the Greek*, from whom the lloman* appear to have 

 derived their architecture, only three. The Egyptian* used columns, 

 but they were very different in their form awl pro|>ortion from both 

 the lloman and Greek example*. Very different again from all these 

 were the column* in Assyrian architecture. I NIHETKU, AKCUITECTUBB 

 OF.] 



[Egyptian Column In the British Museum.) 



The elliptical figures are the cartouches on the column, drawn to a larger 

 scale. The height of the column is 13 ft. 1 1 { In. 



The five Roman orders arc the Corinthian, Ionic, and Composite, 

 which is a mixture of the two former, and the Doric and the Tuscan, 



