CONTENTS. 
IX. Abstract of Observations on a diurnal Variation of the 
Barometer between the Tropics. By J. Horsburgh, Esq. In a 
Letter to Henry Cavendish, Esq. F. R. S. p. 177 
X. Concerning the Differences in the magnetic Needle, on Board 
the Investigator, arising from an Alteration in the Direction of 
the Ship’s Head. By Matthew Flinders, Esq. Commander of 
his Majesty’s Ship Investigator. In a Letter to the Right Hon. 
Sir Joseph Banks, K. B. P R. S. p. 186 
XI. The Physiology of the Stapes, one of the Bones of the Organ 
of Hearing ; deduced from a comparative V iew of its Structure, 
and Uses, in different Animals. By Anthony Carlisle, Esq. 
F. R. S. p. 198 
XII. On an artificial Substance which possesses the principal cha- 
racteristic Properties of Tannin. By Charles Hatchett, Esq. 
F.R.S. p. 211 
XIII. The Case of a full grown Woman in whom the Ovaria were 
deficient. By Mr. Charles Pears, F. L. S. Communicated by 
the Right Hon. Sir Joseph Banks, K. B. P. R. S. p. 225 
XIV. A Description of Malformation in the Heart of an Infant. 
By Mr. Hugh Chudleigh Standert. Communicated by Anthony 
Carlisle, Esq. F. R. S. p. 228 
XV. On a Method of analyzing Stones containing fixed Alkali, by 
Means of the Boracic Acid. By Humphry Davy, Esq. F.R.S. 
Professor of Chemistry in the Royal Institution p. 231 
