Dr. LECONTE expressed his views "On the Geographical Distribution of Coleoptera," which will be published at length in a work now in preparation for the press. After an animated discussion on the subject of the geographical distribution of animals, in which many members took part, it was moved and seconded, that an election be held for Chairman, when Dr. S. G. MORTON was unanimously chosen. The Section then adjourned to meet to-morrow at 10 o'clock, A. M. R. W. GIBBES, Sec'ry. September 21. SECTION OF GENERAL PHYSICS, &c. Morning Session. Pursuant to the order of business, the Section for General Physics met at 10, A. M., in the Chemical Hall of the University. A programme of business was submitted by the Committee, and the first page read was A REPORT ON THE WINDS OF THE NORTHERN HEMISPHERE. BY PROF. J. H. COFFIN. After some remarks upon the importance in investigations of that kind, of lengthened periods of observation, for the purpose of eliminating accidental errors, and of extending the field of research over as wide a field as possible, he proceeded to classify the observations which formed the basis of the report according to the regions or countries in which they were taken. These were widely scattered over both continents, and the Atlantic, Pacific and Arctic Oceans, and embraced an aggregate period of over two thousand years, at 550 fixed stations, beside numerous voyages and tours. A more extensive collection, he remarked, than had ever before been brought together for the purpose. He next proceeded to point out the method he adopted to determine from these observations, the mean course of the wind, which was the same as that by which the traverse of a ship at sea is resolved. By the aid of extensive diagrams, he then proceeded to establish the fact that between lat. 33° and 60°, there is a general current from the west, (or rather from a little to the south of west,) extending entirely round the globe; but that, as we approach those limits, (particularly on the south,) it gradually loses its decided character, and at the limit all trace of a fixed direction disappears, the current at any place being controlled entirely by local influences. This he illustrated by a separate diagram of the winds at Augusta, Geo. After passing this limit, on the south, he showed that a current from the opposite direction sets in, which, as we go south, gradually assumes a more decided character till we come fully within the limits of the trade-winds. He alluded, in passing, to a peculiarity in the winds west of the Mississippi, between lat. 30° and 40°, as explaining the tracks of storms in those regions. North of lat. 60°, he showed that there are indications that the strong current that comes down from the north, in the polar regions, veers toward the west, thus establishing a third system, which breaks up at about lat. 60°. The observations taken at various places, in Russian and British. America, Norway and St. Petersburg, in Russia, were alluded to as indicating this fact. After having gone through with his remarks upon the general course of the winds, he took up the subject of the annual curve which they describe, and showed that while on the eastern coast of Asia it is the same as here, in Europe the curvature seems to be in the opposite direction. Also, that a curvature, physically similar, exists in both the easterly and westerly systems of winds. He next spoke of the relative force of the different winds, showing how far the general results are modified from this cause. After remarking that he was compelled, for want of time, to omit several matters embraced in the report, he closed with an expression of thanks to the numerous friends who had aided him in obtaining the necessary data, and whom he mentioned by name, with the kind of aid received from each. The next subject was A DISCOURSE ON THE FLEXIBLe Surface. BY PROF. B. PEIRCE. [Not received.] Prof. C. U. SHEPHARD, through Prof. B. SILLIMAN, Jr., presented a "REPORT ON METEORITES," which has been published in the American Journal of Science and Arts, November, 1848, p. 402. Dr. LECONTE expressed his views "On the Geographical Distribution of Coleoptera," which will be published at length in a work now in preparation for the press. After an animated discussion on the subject of the geographical distribution of animals, in which many members took part, it was moved and seconded, that an election be held for Chairman, when Dr. S. G. MORTON was unanimously chosen. The Section then adjourned to meet to-morrow at 10 o'clock, A. M. R. W. GIBBES, Sec'ry. September 21. SECTION OF GENERAL PHYSICS, &c. Morning Session. Pursuant to the order of business, the Section for General Physics met at 10, A. M., in the Chemical Hall of the University. A programme of business was submitted by the Committee, and the first page read was A REPORT ON THE WINDS OF THE NORTHERN HEMISPHERE. BY PROF. J. H. COFFIN. After some remarks upon the importance in investigations of that kind, of lengthened periods of observation, for the purpose of eliminating accidental errors, and of extending the field of research over as wide a field as possible, he proceeded to classify the observations which formed the basis of the report according to the regions or countries in which they were taken. These were widely scattered over both continents, and the Atlantic, Pacific and Arctic Oceans, and embraced an aggregate period of over two thousand years, at 550 fixed stations, beside numerous voyages and tours. A more extensive collection, he remarked, than had ever before been brought together for the purpose. He next proceeded to point out the method he adopted to determine from these observations, the mean course of the wind, which was the same as that by which the traverse of a ship at sea is resolved. By the aid of extensive diagrams, he then proceeded to establish the fact that between lat. 331° and 60°, there is a general current from the west, (or rather from a little to the south of west,) extending entirely round the globe; but that, as we approach those limits, (particularly on the south,) it gradually loses its decided character, and at the limit all trace of a fixed direction disappears, the current at any place being controlled entirely by local influences. This he illustrated by a separate diagram of the winds at Augusta, Geo. After passing this limit, on the south, he showed that a current from the opposite direction sets in, which, as we go south, gradually assumes a more decided character till we come fully within the limits of the trade-winds. He alluded, in passing, to a peculiarity in the winds. west of the Mississippi, between lat. 30° and 40°, as explaining the tracks of storms in those regions. North of lat. 60°, he showed that there are indications that the strong current that comes down from the north, in the polar regions, veers toward the west, thus establishing a third system, which breaks up at about lat. 60°. The observations taken at various places, in Russian and British America, Norway and St. Petersburg, in Russia, were alluded to as indicating this fact. After having gone through with his remarks upon the general course of the winds, he took up the subject of the annual curve which they describe, and showed that while on the eastern coast of Asia it is the same as here, in Europe the curvature seems to be in the opposite direction. Also, that a curvature, physically similar, exists in both the easterly and westerly systems of winds. He next spoke of the relative force of the different winds, showing how far the general results are modified from this cause. After remarking that he was compelled, for want of time, to omit several matters embraced in the report, he closed with an expression of thanks to the numerous friends who had aided him in obtaining the necessary data, and whom he mentioned by name, with the kind of aid received from each. The next subject was A DISCOURSE ON THE FLEXIBLE SURFAce. BY PROF. B. PEIRCE. [Not received.] Prof. C. U. SHEPHARD, through Prof. B. SILLIMAN, Jr., presented a "REPORT ON METEORITES," which has been published in the American Journal of Science and Arts, November, 1848, p. 402. A paper was now read— ON THE VOLATILITY OF POTASSA AND SODA, AND THEIR CARBONATES. BY PROFS. W. B. ROGERS AND R. E. ROGERS. This communication detailed the results of numerous experiments, proving that these materials have a much higher volatility than has hitherto been recognised by chemists, and exhibiting the comparative rapidity with which they evaporate when exposed to the heat of the alcohol lamp and that of the blowpipe. When potassa, soda, magnesia and lime, were similarly heated and weighed, from time to time during the process, it was found that potassa was most volatile; soda came next; magnesia was much less volatile than soda; and lime so greatly inferior, in this respect, to magnesia, as to require a long continued high temperature to cause a sensible loss. The carbonates of potassa and soda presented the same order, and nearly the same degree of volatility as the bases themselves. Two separate modes of experiment were adopted. In the one, the substance in solution was dropped in small quantities, on a slip of platina foil, so as when dried to form a delicate tache on the metallic surface. This tache was subjected to the heat of a spirit lamp, by holding the foil in the flame, or again to the stronger heat of this flame, urged by the mouth blowpipe. The change in the tache, in each case, was tested by its alkaline reaction, on delicately prepared turmeric paper. The second method, a weighed quantity of the alkali, or other material, was exposed to the strongest heat of the table blowpipe, and the evaporation marked by weighing at stated intervals. The following extracts, from the register of experiments, will exemplify these methods and their results. I. Experiments with the Tache. The tache, in each case, was formed from one, two or more drops of the particular solution used; so that all the taches in each series were exactly equal. 1. Tache of Potassa on platinum foil having a strong alkaline reaction, heated by the mouth blowpipe for 2", was entirely dissipated. Its place on the metal presented no trace of alkaline reaction. By repeated trials it was found that at this heat a |