5 Use of Soapstone in diminishing Friction 455 6 On peculiar Physical Repulsions _ib._ 7 On the Magnetic Effects of Metals in Motion 456 8 Duration of the Effects of Light upon the Eye 457 9 On the Measurement of the Intensity of Light _ib._ 10 On the apparent Decomposition of White Light by a Reflecting Body when in Motion 458 11 On the Barometer _ib._ 12 Easy method of reducing Barometrical Observations to a Standard Temperature _ib._ 13 Diamond Lenses 459 14 Sapphire Lenses for Single Microscopes _ib._ 15 On a Method of securing and Preserving the Rowing Pins in Boats 460 16 Cold Injection for Anatomical Preparation 461 II. CHEMICAL SCIENCE. 1 Extraordinary Experiments on Heat and Steam 461 2 On the Use of feeble Electric Currents, for effecting the Combination of numerous Bodies 462 3 Crystallization of Metallic Oxides 465 4 On Bromine _ib._ 5 Elementary Nature of Bromine _ib._ 6 Quantity of Bromine in Sea-Water 466 7 Sale of Bromine _ib._ 8 Preparation of Iodous Acid _ib._ 9 On a peculiar Nitric Acid, and Sulphate of Potash 467 10 On certain Properties of Sulphur 468 11 On the Fluidity of Sulphur and Phosphorus at common temperatures 469 12 Separation of Selenium from Sulphur 470 13 On a new Compound of Selenium and Oxygen—Selenic Acid 471 14 Preparation of Hyposulphuric Acid 473 15 Singular Habitude of Phosphoric Acid with Albumen 473 16 Economical Preparation of Deutoxide of Barium 474 17 Preparation of Aluminum—Chloride of Aluminum _ib._ 18 Mutual Action of Lime and Litharge 475 19 New Chloride of Manganese discovered _ib._ 20 Preparation of pure Oxide of Zinc 476 21 Deuto-Sulphuret of Cobalt _ib._ 22 Separation of Bismuth from Mercury by Potassium _ib._ 23 Sulphuret of Arsenic proportionate in Composition to Arsenic Acid _ib._ 24 New Double Chromates 477 25 Dobereiner’s finely divided Platina 477 26 New Metals 478 27 Analysis of Porcelain Pottery, &c. _ib._ 28 On the Composition of simple Alimentary Substances 480 29 Preparation of Sulphate of Quinia and Kinic Acid, without the use of Alcohol 482 30 Pure Narcotine prepared 483 31 Uncertain Nature of Jalapia _ib._ 32 Preparation of pure Mellitic Acid 33 On a New Acid existing in Iceland Moss 484 34 Remarks on the Preparation of M. Gautier’s Ferro-prussiate of Potash, as described in this Journal for July, 1827 _ib._ III. NATURAL HISTORY. 1 Squalls of Wind on the African Shores 486 2 Destruction of an Oak by Lightning 487 3 Description of a Meteoric Fire-Ball seen at New Haven _ib._ 4 Remarkable Meteoric Phenomenon 488 5 Aurora Borealis seen in the Day-time at Cannonmills 489 6 Aurora Borealis in Siberia _ib._ 7 On the Presence of Ammonia in Argillaceous Minerals _ib._ 8 Composition of Apatite 490 9 Burmese Petroleum Wells _ib._