U X A 



bels on general lUlks, nearly as long as the partial ones. Of 

 this alfo we have juft given a defcription. We know nothing 

 of the fhape of the feeds in this fpecies, nor whether they 

 are furnilhed with any appendage, or tunic, at their fear. 

 If they fliould prove to want this charafter, that circum- 

 ftance, added to the gibbous, almoft tubular, neftariferous 

 bafes of their petals, and the great comparative length of 

 their ^laments, with refpeft to the anthers, might almoil 

 lead to their eftabliftiment as a new genus. Before this 

 could be done, however, we ought to be well acquainted 

 with the/r«/V, feeds, and their year, in Streptopus lanugimfus, 

 whofe X.wi\x\ flwdiers connetl thefe two umbellate fpecies with 

 tlie folitary itiflorefcence of the S. amplexifolius and rofeus. 



The concluding paragraph of our article Streptopus 

 fhould now be erafed. 



UvuLARiA, in the Materia Medka, the name given by 

 authors to the plant called hypoghjfum, or double tongue. 



UUZEDERINA, in Geography, a town of Bulgaria, on 

 the Danube ; 50 miles W. of Nicopolis. 



UWCHLAND, a townfhip of Pennfylvania, in Chefter 

 county, containing 1178 inhabitants. 



UXACONA, in Jncient Geography, a. town of Great 

 Britain, in Antonine's fecond Itin., marked between Uri- 

 conium (Wroxeter) and Pannocrucium (at or near the river 

 Penk, and town of Penkridge). Dr. Gale and Mr. Cam- 

 den place Uxacona at Okenyale, and Mr. Baxter at New- 

 port ; but Mr. Horfley, following the traft of the military 

 way, and obferving the diitance, fixes it at the banks of a 

 rivulet near Sheriff-Hales. 



UXAHVER, Ox-spring, a boiling fountain of water, 

 about a mile from a place called Hufavik, in the north of 

 Iceland, not far from Skalholt, more regular, and nearly 

 equal to the Gcyfer in the magnificence of its operations. 

 It is faid that this name was given to it from the circum- 

 ftancc of an ox having fallen into it by accident, and having 

 been boiled alive. 



We ihall here add, that the Geyfers are celebrated foun- 

 tains, about 16 miles N. of Skalholt, fituated in a country 

 indicating many traces of volcanic eruptions. They lie on 

 the fide of a hill, which does not exceed 300 feet in height, 

 and which is feparated from the mountain towards the W. 

 by a narrow ftripe of flat boggy ground, connefted with 

 that which extends over the whole valley. On the E. fide 

 of the hill there are feveral banks of clay, from fome of 

 which fteam arifes in different places, and in others there 

 are cavities in which the water boils briflvly. Below thefe 

 banks there is a gentle flope, compofed of matter, which, 

 at fome diilant period, has been depofited by fprings that no 

 longer exilt. The flrata or beds thus formed fecm to have 

 been broken by the flincks of earthquakes, particularly near 

 the Great Geyfer. Within the fpace of about a nnle there 

 are numerous orifices in the old incruftations, from which 

 boiling water and fteam ilTue, with different degrees of force ; 

 and at the northern extremity is the Great Gcyfer, fufli- 

 ciently diilniguirtiable from the others by every circumllance 

 connected with it. Aniidil the depofitions of matter is a 

 mount about feven feet high, lying on the W. fide, where a 

 difruption has taken place. On the top of this mount is a 

 bafon, extending 56 feet in one direction, and 46 in another. 

 The bafon v.-as full of hot water, a httle of which was run- 

 ning over. Above the Great Geyfer, and near it, is a large 

 irregular opening, the beauties of which it is hardly pofii- 

 ble to defcribe. The water which filled it was as clear as 

 cryftal, and perfeftly ftill, though nearly at the boiling 

 point. Through it were feen white incruftations, forming 

 a variety of figures and cavities, to a great depth ; and be- 

 low was perceived a vaft and dark abyfs, over which the 



7 



U X A 



cruft. that fupported the obfervers formed a dome of no 

 great thicknefs ; a circumftance which contributed much to 

 the effed of this awful fcene. Near this fpot are feveral 

 holes, from which vapour continually rifes ; and from one 

 of which a rumbhng noife proceeded. One of the moft re- 

 markable of thefe fprings threw out a great quantity of 

 water ; and from its continual noife it was called the Roar- 

 ing Geyfer. The eruptions of this fountain were inceffant. 

 The water dalhed out with fury every four or five minutes, 

 and covered a great fpace of ground with the matter it de- 

 pofited. The jets were from thirty to forty feet high. They 

 were fluvercd into the fineit particles of fpray, and fur- 

 rounded by great clouds of fteam. The fituation of this 

 fpring was eighty yards diftant from the Geyfer, on the fide 

 of a hill. It is probable that an earthquake has damaged 

 the mechanifm of this fpring, or the produftion of heat, at 

 the particular fpot where it is fituated, has ceafed to be fuf- 

 ficient to produce the phenomena which it formerly exhi- 

 bited. In collefting incruftations near the bafon, and 

 ftriking on its brink many blows with a hammer, a found 

 was heard like the diftant difcharge of a piece of ordnance, 

 and the ground fhook. The found was irregul.irly and 

 rapidly repeated ; and then the water, after having feveral 

 times fuddenly rifen in a large column, accompanied by clouds 

 of fteam, from the middle of the bafon to the height of ten 

 or, twelve feet, the column feemed as if it burft, and fink- 

 ing down, it produced a wave which caufed the water to 

 overflow the bafon in confiderable quantity. After the firfl; 

 propulfion, the water was thrown up again to the height of 

 about 15 feet ; and there was a fucceffion of jets, to the num- 

 ber of eighteen, none of which appeared to exceed fifty feet iu 

 height, and they lafted about five minutes. After the laft 

 jet, which was the moft furious, the water fuddenly left the 

 bafon, and funk into a pipe in the centre. The heat of the 

 bafon foon made it dry, and the wind blew afide the vapour 

 almoft immediately after the fpouting ceafed. The pipe, 

 into which tlie water had fimk about ten feet, was imme- 

 diately examined, and it appeared to be riling llowly. The 

 diameter of the pipe, or rather pit, is 10 feet, widening 

 near the lop to 16 feet. The perpendicular depth of the 

 bafon is three feet, that of the pipe is fomewhat more than 

 60 feet. When the water was Hill, ftones were thrown 

 into the pipe, and a violent ebullition followed. The tem- 

 perature of the water within reach, when the pipe was full, 

 was found to be 209°. At repeated intervals frefh jets oc- 

 curred, none of which exceeded 30 feet in height. But we 

 have not room to enlarge in the detail of various other cir- 

 cumftances obferved by tliofe who examined thefe extraor- 

 dinary fountains. The depofitions of the prefent and former 

 fprings are vifible to a great extent, about half a mile in 

 every direftion, and they probably extend themfelves under 

 the furfacc, now covered with grafs and water to a very 

 coiifiderable diftance. 



Ahhough hot fprings occur in every part of the country, 

 the Geyfers are the moft remarkable, and muft have exiiled 

 for a long time ; but as they are lituated on the verge of that 

 valt diftrift of uninhabited and defolate country which 

 forms the interior of Iceland, they have not been parti- 

 cularly noticed by the early Icelandic authors ; nor are they 

 now much vifited by the natives. In order to account for 

 the phenomena exhibited by the operations of thefe fprings, 

 it is fuppofed that they are occafioned by fudden produc- 

 tions of heat, whatever may be the caufes of that heat. A 

 column of water is fufpended in a pipe by the expanfive 

 force of fteam confined in cavities under the furface. An 

 additional quantity of fteam can only be produced by more 

 heat being evolved. The heat is fuddenly evolved, and 



elaftic 



