STOP Early Journal Content on JSTOR, Free to Anyone in the World This article is one of nearly 500,000 scholarly works digitized and made freely available to everyone in the world by JSTOR. Known as the Early Journal Content, this set of works include research articles, news, letters, and other writings published in more than 200 of the oldest leading academic journals. The works date from the mid-seventeenth to the early twentieth centuries. We encourage people to read and share the Early Journal Content openly and to tell others that this resource exists. People may post this content online or redistribute in any way for non-commercial purposes. Read more about Early Journal Content at http://about.jstor.org/participate-jstor/individuals/early- journal-content . JSTOR is a digital library of academic journals, books, and primary source objects. JSTOR helps people discover, use, and build upon a wide range of content through a powerful research and teaching platform, and preserves this content for future generations. JSTOR is part of ITHAKA, a not-for-profit organization that also includes Ithaka S+R and Portico. For more information about JSTOR, please contact support@jstor.org. 317 On the Electrical Relations of Metals and Metalliferous Minerals, By It. W. Fox, Esq. Communicated in a letter to Davies Gilbert, Esq., F.R.S. The author states that he has ascertained that the crystallized gray- oxide of manganese holds a much higher place in the electro-mag- netic scale than any other body with which he has compared it, when immersed in various diluted acids, and alkaline solutions : he also gives a table of the order in which other metals and minerals stand in this respect. When employed in voltaic combinations he found that on being so arranged as to act in opposition to one another, the di- rection of the resultant of their action, as indicated by the deflection of the magnetic needle, did not coincide with the mean of the direc- tions of the needle when under the separate influence of each. Hence he infers that the needle is not a true index of the electricity trans- mitted; and that electro-magnetic action does not depend on a con- tinuous electric current. He conceives, therefore, that the pheno- mena are better explained on the hypothesis of pulsations which he formerly advanced. A galvanometer of a new construction is em- ployed by the author for weighing the deflecting force of these elec- trical impulses. On the Circulation of the Blood in Insects. By John Tyrrell, Esq., A.M. Communicated by P. M. Roget, M.D., Secretary 'to the Royal Society. The observations on the circulation of the blood in insects, which is a discovery of comparatively recent date, have been made almost exclusively on insects in the larva state ; but the author of the pre- sent paper details a variety of observations of the same fact in insects which had arrived at their last or perfect stage of development. Among the Myriapoda, the circulation was traced in the Geophilus, and still more distinctly in the Lithobiusforficalus. The author also detected the circulation, by the motion of globules, through the ner- vures of the wings of various perfect insects, namely, of some species of the Hemerobius, Panorpa, Phryganea, and Ephemera ; and par- ticularly in the Muxca domestica, or common house-fly. The paper is accompanied by drawings of the appearances described. January 22, 1835. JOHN WILLIAM LUBBOCK, Esq., Vice-President and Trea- surer, in the Chair. A paper was read, entitled, " Notes on the Temperature of the Air and the Sea, &c, made in a Voyage from England to India, in the Ship Hoogly, Capt. Reeves, in the year 1833." By Alexander Burnes, Esq., F.R.S. The observations contained in this communication are recorded in a tabular form, and show that the variations of the temperature of the sea accord very closely with those of the air, in all the latitudes which the author traversed in this voyage.