11 
CONTENTS. 
Art. XIII. On the Length of the Seconds Pendulum, observed 
at Unst, the most northern of the Shetland Isles. 
By M. Biot, Member of the Institute, F. R. S. &c. 77 
V. Description of an Improved Self-acting Pump. By 
James Hunter, Esq. of Thurston, - 79 
XV. Account of a New Method of making Single Micros- 
copes of Glass, proposed and executed by Thomas 
SivRiGHT, Esq., F. R. S. Edin. and F. A. S. E. 81 
XVI. Remarks on the Size of the Greenland Whale, or Ba- 
laena Mysticetus. By William Scoresby junior, 
F.R.S. Edin. & M.W.S. - - 83. 
XVII. Account of the Recent Discoveries in Egypt respect- 
ing the Sphinx and the Great Pyramid, - 88 
XVIII. Observations on the Arctic and Skua Gulls of British 
Ornithologists. By the Rev. John Fleming, D. D. 
, F. R. S. Edin. M. W. S. - - 97 
XIX. Description of the Nautical Top, as constructed by 
Edward Troughton, F. R. S., - 105 
XX. On the Geognostical relations of Granite, Quartz- Rock, 
and Red Sandstone. By Professor Jameson, 109 
XXL Account of an Improved Hygrometer. By John Li- 
vingstone, M. D. of Canton, - - 116 
XXII. On the Temporary Residences of the Greenlanders 
during the Winter Season. By Sir Charles Gie- 
secke. Professor of Mineralogy to the Dublin 
Society, M. W. S. &c. - - II7 
XXIII. Narrative of an Excursion upon the Island of Jan 
Mayen. By William Scoresby jwmor, F. R. S. 
Edin, and M. W. S. . _ - 221 
XXIV, Notice respecting the Journey to the Sources of the 
Jumna and the Ganges, by J. B. Fraser, Esq. 127 
XXV. On the Black Lead of Borrodale, of Ayrshire, and 
of Glenstrathfarrar. By Professor Jameson, 130 
XXVI. On the Temperature of Air and of Water in the 
Coal-Mines of Great Britain. By Robert Bald, 
F.R. S. Edin. M.G.S.& M.W.S. - 134 
XXVII. 1. Secondary Greenstone and Wacke not of Volca- 
nic Origin, 2. Veins which connect Mineral 
Beds together not confined to Trap-rocks, 3. Trap 
Veins (Whin-dikes) probably of cotemporaneous 
Formation with the trap-rocks which they tra- 
> verse. By Professor Jameson, - 138 
