The following papers were read, viz. :
1. " Meteorological Register kept at Port Arthur, Van Diemen's Land, during the year 1838, and Register of Tides at Port Arthur, from August 1838 to July 1839, both inclusive." By Deputy- Assistant-Commissary- General Lempriere. Communicated by Sir John Franklin, R.N., F.R.S., &c.
2. " Notice relative to the form of the Blood-particles of the Ornithorhynchus hystrix." By John Davy, M.D., F.R.S.
A portion of the blood of the Ornithorhynchus hystrix, mixed when fresh with a strong solution of common salt, being examined by the author, exhibited a few globules of irregular shape. Another portion, preserved in syrup, contained numerous globules, most of which had an irregular form, but many were circular ; none, how- ever, were elliptical, like those of birds. Hence the author con- cludes, that in form they accord more with those of Mammalia.
3. " Researches on Electro-chemical equivalents, and on a sup- posed discrepancy between some of them and the atomic weight of the same bodies, as deduced from the theory of isomorphism." By Lieut. -Colonel P. Yorke. Communicated by Michael Faraday, Esq., D.C.L., F.R.S., &c.
The author describes various experiments made with a view to determine the electro- chemical equivalents of sodium and potassium. Three experiments gave, respectively, 22*3, 22*9, and 25, as the equivalent of the former ; and two other experiments gave, respec- tively, 45 and 41*7, as the equivalent of the latter of these sub- stances. He then inquires what would be the result of the electro- lyzation of the aqueous solutions of soda and potash, on the hypo- thesis of these bodies being composed of two equivalents, or atoms, of metal, and one of oxygen. To determine this question he em- ploys a solution of dichloride of copper in muriatic acid, as being a substance composed of two atoms of metal and one of an electro- negative element. Its electrolysis gave as the equivalent of copper, 52" 8, 59*4, and 61" 6, numbers approximating closely to 63*2, or double the atomic weight of copper. After a long train of investi- gation, he concludes that there is no reason deducible from the theory of isomorphism for doubting the correctness of the received atomic weights of silver, sodium, &c., but that the difficulty, or anomaly, if it may be so called, should be considered as attaching itself to the di- compounds of copper; and that Faraday's proposi- tions on this subject remain unimpeached.
4. Second series of AjDproximate Deductions made from about 50,000 observations taken during the 3^ears 1836, 1837, and 1838, at the P. Louis Observatory, Mauritius, four times each day; namely, at 8 a.m., at noon, and at 4 and Sf.m." By J. A. Lloyd, Esq., F.R.S.
5. " On the Solubility of Silica by Steam ; with an account of an experiment on the subject, conducted in the East Indies by
