lies 



URAN-BLOOM. 



URINE. 



lies 



100 100-4 



Tliis mineral is evidently a mere mixture of OxiJe of Uranium, 

 with other substances, and, besides those above enumerated, Arfwed- 

 son found the oxides of arsenic, zinc, and copper, in the Pitchblende of 

 Joachimsthal. 



Chalcolite, Green Uranite, CwprtO-Pkapkale of I'ranium. This 

 Mineral agrees with the preceding in crystalline form, but differs in 

 colour, it being grass- or emerald-green, owing to the presence of phos- 

 phate of copper instead of phosphate of lime. It occurs in Cornwall, 

 was first shown to contain uranium by the Rev. Mr. Gregor, and 

 analysed afterwards by R. Phillips and subsequently by Berzelius ; the 

 results of the experiments gave as its composition 



Phosphoric Acid . 

 Oxide of Uranium 

 Oxide of Copper . 

 Water . 

 Stony Matter 



16-0 

 60-0 

 .9-0 . 

 14-5 

 0-5 



Bcrzelius. 

 15-56 

 60-25 



8-44 

 15-05 



0-70 



100 100 



Urantte, Uran-Mica, Calcareo-Phoiphale of Uranium occurs crystal- 

 lised. Primary form a square prism. Cleavage parallel to the terminal 

 planes, very distinct. Fracture foliated. Hardness : scratches sulphate 

 of lime, and is scratched by the carbonate. Colour lemon- or golden- 

 yellow, and yellowish-brown. Lustre adamantine. Transparent, 

 translucent. Specific gravity 3'12 to 3'33. It is found in veins in 

 granite at St. Symphorien near Autun, and at St. Yrieux near Limoges 

 in France, and also in several places in Saxony. An analysis of a 

 specimen from Autun by Berzelius gave : 



Phosphoric Acid 14-63 



Oxide of Uranium "59'37 



Lime ........ 5-66 



Silica and Oxide of Iron 2'85 



Magnesia and Oxide of Manganese . . 0'19 



Barytes 1-51 



Water 14-90 



Fluoric Acid and Ammonia . . . . Traces 



99-11 



This mineral appears essentially to consist of the phosphates of 

 uranium and lime. 



Carbonate of Uranium, Uran-Bloom, Uraconite, occurs in small in- 

 distinctly crystalline flakes. Lustre but slight. Colour bright-yellow. 

 Occurs in silver-veins at Joachimsthal in Bohemia, forming a coating 

 on pitchblende. 



^nljihale of Uranium. This occurs as a thin botryoidal yellow- 

 coloured coating over the surface of the minerals on which it is found. 

 It is friable, and soils the fingers. Partially soluble in water, and the 

 remainder in nitric acid ; both solutions contain sulphate of uranium, 

 and are of a yellow colour. It is found at Joachimsthal in Bohemia. 

 Sulphate of Uranium and Copper, Juhannite, occurs crystallised. 

 Primary form an oblique rhombic prism. Crystals very minute. 

 Fracture imperfect conchoidal. Hardness 2 to 2'5. Taste slightly 

 bitter. Partially soluble in water. Colour deep grass-green. Streak 

 paler. Lustre vitreous. Translucent. Specific gravity 3'19. It occurs 

 at Joachimsthal in Bohemia, and has not been quantitively analysed. 



Samankite, Uranotantalite, Yttroilmenite, is a compound of oxide of 

 uranium with niobic and tungstic acids. From Miask and the Ural. 

 URAN-BLOOM. [URANIUM.] 

 URAN-MICA. [URANIUM.] 

 URANOCENTRON. [IOUANIDJE.] 



URANO'SCOPUS, a genus of Acanthopterygious Osseous Fishes of 

 the Perch Family, and very nearly related to the Weavers ( Trachiurus) 

 of the British seas. One or two species inhabit the Mediterranean. 

 The bead is nearly cubical, and the eyes placed in the flat summit, so 

 that they look upwards : hence the name. The mouth is turned up in 

 a similar manner. Thin arrangement agrees with the habits of the 

 fish, which buries itself in sand all but the summit of the head, and 

 thus lies in wait for its prey. Its colour resembles the sand in which 



URANOTANTALITE. [URANIUM.] 



UHAO, a variety of Sesqni-Carbonate of Soda. [SODIUM.] 



URARI. [STKvniNos] 



IJ'KCKOLA, a genua of Plants belonging to the natural order 

 Aporynacta, do named by Dr. Roxburgh from urceolus, 'a pitcher," in 

 consequence of the form of its corollx. The genus Urceola is con- 

 fined to the Malayan peninsula, and the islands of Sumatra and 

 Penang ; but tut it is by some botanists considered not to differ from 

 the Vahea of Madagascar, the genus may have a wider distribution. 

 It had the calyx small, 6-partite. Corolla urceolato; tube elongated, 



ventricose, 5 cleft. Stamens 5, anthers sagittate. Follicles 2 ; seeds 

 numerous, glabrous. 



U. elaitica, or Caoutchouc-Vine, is shrubby and twining, climbing 

 over trees to a great extent, sometimes as much as 200 paces; with 

 oval opposite leaves, nd terminal panicles. From wounds made in 

 the bark of this plant there oozes out a milky fluid, which on expo- 

 sure to the open air separates into an elastic coagulum, and watery 

 liquid apparently of no use. After the separation takes place, this 

 coagulum is not only like American Caoutchouc, or Indian-Rubber, 

 but possesses all the same properties a* first ascertained by Dr. Rox- 

 burgh ('Asiat. Res.,' v. 171.) He states that a ball of it externally 

 has the appearance of American Caoutchouc; when cut into, it is of 

 a light brown colour, till the action of the air darkens it. This ball, 

 measuring 9J iuches in circumference, and weighing 7.f ounces, in 

 simply falling from a height of 15 feet, rebounded about 10 or 12 

 times, which is of itself an indication of the goodness of the Caout- 

 chouc. Dr. Roxburgh also found that slips of it were capable of 

 bearing a greater degree of extension and contraction than the Ameri- 

 can. When they broke, the elasticity was so great, that each end 

 returned to its respective mass. The least pressure with the finger 

 and thumb united different portions as perfectly as if they had never- 

 been separated : this property of Caoutchouc has been considered a 

 much more modern discovery. [INDIAN-RUBBER.] 



URCKOLA'RIA, a genus of Crustaceous Lichens, belonging to Fde's 

 family Lecanontz. The characters of this genus are as follows : 

 Thallus crustaceous, spreading, aduate, uniform ; the apothecia, repro- 

 ductive organs, are orbicular, with the disc concave, coloured, and 

 immersed in the crust ; the border of the apothecium is formed of 

 the crust, and has the same colour. Hooker, in his ' British Flora," 

 enumerates six British species of Urceolaria. They are generally 

 found on rocks, stones, and walls. Two of the species U. scruposa, 

 the Common Urceolaria, and U. cinerea, the Gray Urceolaria, are used 

 for dyeing. 



URCHIN. [EBINACEUS.] 



URCHIN, SEA. [ECHINIDA] 



UREDINACE^E, a family of Fungi, belonging to the sub-order 

 Sporiferi. It includes the various forms of Fungi which occur on 

 diseased vegetable tissues, and which are hence called Blights. The 

 spores are single, often partitioned on more or less distinct sporophores, 

 Socci of the fruit obsolete or mere peduncles. [FDNOi.] 



URE'DO. [Fuuui.] 



URE'NA, a genus of Plants belonging to the natural order Malna- 

 cece. Like other Malvaoeous plants, the species of Urena, abound in 

 strong and serviceable nax-like fibres, which are well fitted for conver- 

 sion into cordage. U. lubata and 17. sinuata are specially mentioned 

 as employed for this purpose in India. 



URKTER. [BLADDER.] 



URE'THRA. [BLADDER.] 



URIA. [GUILLEMOTS.] 



URINARY SYSTEM. [URINE.] 



URINARY ORGANS. [KIDNEYS.] 



URINE is a fluid secreted from the blood by the kidneys. This 

 fluid in a healthy person when recently voided is acid, transparent, 

 usually of a pale amber or straw-colour, of a brackish taste, peculiar 

 odour, and of a specific gravity varying from 1-010 to 1-030. The 

 character of the urine however is apt to be altered by a variety of 

 circumstances : it differs, for instance, according to the time of the 

 day at which it is passed, whether before or after a meal, and according 

 to the quantity and quality of the food and drink consumed. Urine 

 has therefore been divided into two kinds, that of assimilation, and 

 that of the blood. The urine of the blood is that voided at a consi- 

 derable time after food has been taken, when the process of digestion 

 is complete, and the chyle has entered the blood : it has the properties 

 of urine in an eminent degree, and from it we aro enabled to learn the 

 state of the kidneys and system in general. The urine of assimilation 

 varies, being sometimes limpid and colourles", when a great quantity 

 of fluids has been taken ; at other times, after a full and solid meal, of 

 a deep colour, and becoming turbid on cooling. 



The character of the urine is affected by the seasons ; in winter the 

 kidneys are excited to greater activity than in summer, nor is the 

 reason of this difficult of explanation. All the emunctories of the body 

 act, as occasion may require, as mutual suppeditories. Now, in cold 

 weather the perspiration is more or leas suppressed ; and were it not 

 that the action of the kidneys was iucreased, we should be liable to 

 plethoras, or repletions of the most dangerous nature. Hence it 

 happens that when the perspiration is abundant, the urine is scanty 

 and high coloured, and contains a strong impregnation of saline 

 ingredients ; when the perspiration is checked by any cause, the urine 

 is copious, limpid, and its proper salts more diluted. The state of the 

 mind has also a great influence on the urine : any sudden shock 

 usually increases the quantity of this fluid, and it is then almost 

 without odour or flavour, like water. 



The colour of the urine of persons in health is usually of a pale 

 amber colour, becoming slightly turbid towards the centre, seven or 

 eight hours after having been passed, and shortly depositing a sedi- 

 ment, that rises up in the form of a cone from the centre of the fluid. 

 This deposition, which at first is in small quantity, increases until 

 putrefaction renders the whole of the urine turbid. The colour of 



