THE 



EDINBURGH ENCYCLOPEDIA; 



CONDUCTED DY 



DAVID BREWSTER, L L. D. 



F. R. S. LOND. AND ED1N. AND M. R. I. A. 



CORRESPONDING MEMBER OK THE ROYAL ACADEMY OF SCIENCES OF PARIS, AXD OF THE ROVAL ACADEMY OF SCIENCES OF 



PRUSSIA ; M: .1111, u OF THE ROYAL SWEDISH ACADEMY OF SCIENCES ; OF THE ROYAL SOCIETY OF SCIENCES OF DENMARK ; OF 

 THE ROYAL SOCIETY OF GOTTINGEN, AND OF THE ROYAL ACADEMY OF SCIENCES OF MODENA ; HONORARY ASSOCIATE OF THK 

 ROYAL ACADEMY OP SCIENCES OF LYONS; ASSOCIATE OF THE SOCIETY OF CIVIL ENGINEERS; MENDER OF THE SOCIETY OF THE AN- 

 TIUUARIFS OF SCOTLAND ; OF THE GEOLOGICAL SOCIETY OF LONDON, AND OF THE ASTRONOMICAL SOCIETY OF LONDON ; OF THE 

 AMERICAN ANTIQUARIAN SOCIETY ; HONORARY MEMBER OF THE LITERARY AXD PHILOSOPHICAL SOCIETY OF NEW YORK, OF THK 

 HISTORICAL SOCIETY OF NEW YORK; OF THE LITERARY AND PHILOSOPHICAL SOCIETY OF UTRECHT; OF THE PHILOSOPHICAL 

 M>I MTV OF CAMBRIDGE; OF THE LITERARY AND ANTIQUARIAN SOCIETY OF PERTH; OF THE NORTHERN INSTITUTION, AND OF 

 THE ROYAL MCDICAL AND PHYSICAL SOCIETIES OF EDINBURGH; OF THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA; OF 

 THE SOCIETY OF THF. FRIENDS OF NATURAL HISTORY OF BERLIN; OF THK X VTl'RAI. HISTORY SOCIETY OF FRANKFORT; OF THK 

 PHILOSOPHIC II. AND LITERARY SOCIETY OF LEEDS, OF THK ROYAL GEOLOGICAL SOCIETY OF CORNWALL, AND OF THE PHILOSOPHICAL 

 SOCIETY OF YORK. 



WITH THE ASSISTANCE OF 



GENTLEMEN EMINENT IN SCIENCE AND LITERATURE. 



IN EIGHTEEN VOLUMES. 



VOLUME VI. 



EDINBURGH: 



PRINTED FOR WILLIAM BLACKWOOD ; 



AND JOHN WAUGH, EDINBURGH; JOHN MURRAY; BALDWIN & CRADOCK ; 

 J. M. RICHARDSON, LONDON ; AND THE OTHER PROPRIETORS. 



M.DCCC.XXX. 



