TRANSACTIONS, OF THE ROYAL SOCIETY OF LONDON. FOR THE YEAR MDCCCX. PART II. LONDON, PRINTED BY W. BULMER AND CO. CLEVELAND-ROW, ST. JAMES'S; AND SOLD BY G. AND W. NICOL, PALL-MALL, BOOKSELLERS TO HIS MAJESTY, AND PRINTERS TO THE ROYAL SOCIETY. MDCCCX, CONTENTS. VII. SUPPLEMENT to the First and Second Part of the Paper of Experiments, for Investigating the Cause of Coloured Con- centric Rings between Object Glasses, and other Appearances of a similar Nature. By William Herschel, LL. D. F.R. S. VIII. On the Parts of Trees primarily impaired by Age. In a Letter from T. A. Knight, Esq. F.R.S. to the Rt. Hon. Sir Joseph Banks, Bart. K. B. P.R.S. IX. On the Gizzards of Grazing Birds. By Everard Home, X. Observations on Atmospherical Refraction as it affects astro- nomical Observations; in a Letter from S. Groombridge, Esq. to the Rev. Nevil Maskelyne, D. D. F. R. S. Astronomer Royal. Communicated by the Astronomer Royal. p. 190 XI. Extract of a Letter from the Rev. John Brinkley, D. D. F. R. S. Andrews Professor of Astronomy in the University of Dublin, to the Rev. Nevil Maskelyne, D. D. F. R. S. Astro- nomer Royal, on the annual Parallax of a Lyræ. p. 204 XII. On the Mode of breeding of the Oviviviparous Shark, and on the Aeration of the fœtal Blood in different Classes of Animals. XIII. On Cystic Oxide, a new species of Urinary Calculus. By William Hyde Wollaston, M.D. Sec. R. S. p. 223. XIV. Researches on the oxymuriatic Acid, its Nature and Combinations; and on the Elements of the muriatic Acid. With some Experiments on Sulphur and Phosphorus, made in the Laboratory of the Royal Institution. By H. Davy, Esq. Sec. R. S. Prof. Chem. R. I. F.R.S. E. p. 231 XV. Observations upon Luminous Animals. By J. Macartney, Esq. Communicated by Everard Home, Esq. F.R.S. p. 258 XVI. Observations and Experiments on Pus. By George Pearson, M.D. F.R.S. p. 294 Presents received by the Royal Society, from November, 18c9, to July, 1810. Index. P. 319 p. 325 PHILOSOPHICAL TRANSACTIONS. VII. Supplement to the First and Second Part of the Paper of Experiments, for Investigating the Cause of Coloured Concentric Rings between Object Glasses, and other Appearances of a similar Nature. By William Herschel, LL.D. F.R. S. Read March 15, 1810. WHEN the intricacy of the subject, on which my two last papers have been treating, is considered, it will not appear singular that a few supplementary articles should be given. The compression of the account of the experiments into a small compass, where many material circumstances must be left unnoticed, may throw some obscurity on the results, which can only be removed by examining the subject in a fuller extent, and from various points of view. I hope the following illustration and additional explanations will have the effect of clearing up what may possibly to some appear obscure or doubtful, in either the first or second part of my paper, and serve also to make the conclusions, which in the second have been chiefly supported by prismatic experiments, directly |