CONTENTS 
OF 
No. IV. 
Art I. On Peat. By John MacCulloch^ M. D. M. G. S. Leo 
turer on Chemistry to the Board of Ordnance, &c. 
Communicated by the Author, - Page 201 
II. Account of the Seven Icebergs of Spitzbergen. By 
^ ^ William Scoresby, Esq.y«w. F. R. S. E. & M.W.S., 217 
III. Account of the Malleable Iron Passage-Boat, now ply- 
ing on the Forth and Clyde Canal. In a Letter from 
John Robison, Esq. F. R. S. E. to Dr Brewster, 222 
IV. Sketch of the Distribution of Recks in Shetland. By 
Samuel Hibbert, M. D. F. R. S. E, & M. W. S. &c., 224 
V. Account of the Electrical Eelsjand of the Method of catch- 
ing them in South America by means of Wild Horses. 
Abridged from -Humboldt’s Personal Narrative, 242 
VI. Observations on Mr Menge’s Account of his Mine? alo- 
gical Journey in Iceland. In a Letter from Sir G. S. - 
Mackenzie, Bart. F. R. S. L. and President of the 
Physical Class of the Royal Society of Edinburgh, &c. 
to Professor Jameson, - - 249 
VII. Account of the Trap and Clay-slate Formation extend- 
ing from Llandegly to Builth in Brecknockshire. In 
R Letter from Dr Gilby to Professor Jameson, 253 
VHI. Description of a New Perspective Machine. By the 
late James Watt, Esq. LL. D. F. R. S. Lend, and Ed. 
Member of the National Institute of F ranee, &c. 259 
IX. An Account of a Map of the Countries subject to the 
King of Ava, drawn by a Slave of the King’s Eldest 
Son. By Francis Hamilton, M. D. & F. R. S, & 
F. A. S. Lond. & Edin. Communicated by the Author, 26*2 
X. On the Changes of Colour in the Feathers of Birds, 
independent of Moulting. In a Letter from the Rev. 
John Fleming, D. D. F. R. S. E. & M. W. S. to Pro- 
fessor Jameson, - - 271 
