spores resisted rather strong solutions of silver nitrate, iodin, potassium iodid, and soda.

The suppression of bacteria by means of lysol, J. WEIFS (Pharm. Ztg., 40 (1895), p. 406).

Bactericidal action of metals, E. F. SMITH (Amer. Nat., 29 (1895), No. 346, pp. 933-936).-A review is given of a paper by M. Bolton on "The effects of various metals on the growth of certain bacteria."

The streptococcus and antistreptococcic serum, A. MARMOREK (Ann. Inst. Pasteur, 9 (1895), No. 7, pp. 593–620, figs. 5).

METEOROLOGY.

Papers in terrestrial magnetism and atmospheric electricity (U. S. Dept. Agr., Weather Bureau Bul. 11, pt. 2, Rpt. Internat. Meteorolog. Congress 1893, pt. 2, pp. 460-583, Pls: XIV-XXV).

(1) Magnetic survey of North America, C. A. Schott (pp. 460-464).An account of the discovery of points in the Atlantic agonic line by Columbus, 1492, and Cabot, 1497; of the contributions to magnetic data by Drake, Hudson, Champlain, Baffin; of the Del Arcano del Mare and Gilbert's De Magnete. Also an account of the advances in the present century as contributed by Humboldt 1798–1803, Lefroy 1842–244, Sabine 1840-45, Kane 1853-255, Hayes 1860-'61, Hall 1871, Nares and Markham 1875-'76, Greely 1881-'84; and especially by the operations of the observers of the United States Coast and Geodetic Survey at Philadelphia 1840-45, Key West 1860-'66, Madison 1878-'81, Los Angeles 1882-'89, and San Antonio 1890-'93. The work at Toronto and Washington (United States Naval Observatory) and the Stations of the International Polar Research Expeditions at Uglaamie, Alaska, and Fort Conger, Grinnell Land, 1882-'83, is recounted, together with that of several other exploring expeditions.

(2) Magnetic survey of Europe and Asia, A. de Tillo (pp. 465-469, Pl. XIV).—A sketch is given of the surveys of the several countries, with an attempt to estimate the completeness of the same at the present time. Sabine's charts 1872-76 give the summary of our knowledge up to the year 1850. For the British Islands the latest authority is Rücker and Thorpe, 1890, and is regarded of great value. For France the earlier work of Lamont 1856-57 is supplemented by that of Mascart and Moreaux 1866, and is rated first class. For Germany the survey of Lamont 1844-59 and the partially completed work of Neumayer is also in the first class. For Austria-Hungary the investigations of Kreil 1843-254 and Schenzl 1864-'81 are the most prominent. For Russia the work of Hansteen, Smirnow, Wild, Tillo, and others have covered a large region, but with sufficient completeness to be rated only second class. For India the surveys of the brothers Schlagintweit 1854-58, and for Indo-Malaia those of Elliot and Van Rijckevorsel are the chief authorities, the completeness being second class. For

Siberia, China, and Arabia third rate surveys have been taken. A map shows the areas of these surveys and the regions of no observations. (3) The international polar expeditions, 1882-'83, C. Börgen (pp. 469– 485). The survey of the polar regions had been confined to a few observations by exploring expeditions till the year 1882, when the plan of Weyprecht was put in operation for a series of simultaneous observations surrounding the poles. An account is given of the several preliminary congresses, and the plan of operations finally formulated, the occupation of 12 stations in the Northern Hemisphere and 2 stations in the Southern, with many coöperating stations in lower latitudes. An interesting report of the success of most of the expeditions follows, and a graphic picture of the hardships of Greely's retreat from Fort Conger. A very intelligent summary of the scientific results is given, the value of the material secured, and the chief lesson of failure in the attempt to draw accurate observations from instruments whose operation depends upon the induction of soft iron.

(4) The discovery of magnetic declination made by Christopher Columbus, Fr. T. Bertelli, Ba (pp. 486-492).-The author advances a series of arguments to show that the declination of the magnetic needle was not known before the time of Christopher Columbus, and that he discov ered the same on his first voyage to America. The Chinese knew only the rough directive use of the needle; the Mediterranean navigators were also without knowledge of the declination, as proven by examination of their charts, by their instructions for navigation, by the roses or rhombi on the charts, by the coast lines of the earlier geographical maps as compared with the latter. The arguments in favor of the discovery by Columbus are the facts that he adjusted his compasses to sat isfy the fears of his pilots; that his son Fernando distinctly attributed the discovery to him ("no one had known of such a variation till then"); that the agonic line gave rise to the boundary between the Spanish and Portuguese possessions, and that this discussion began after the first voyage of Columbus.

(5) The cosmical relations manifested in the simultaneous disturbances of the sun, the aurora, and the terrestrial magnetic field, S. Lemström (pp. 492-500, Pl. XV).-An account is given of the discovery and illustration of the connection between sun spots, auroras, and magnetic variations, by Baué Wolfe, Fritz, and Loomis. The extension of their relation to meteorological variations by Bigelow is also described. The author mentions the several theories advanced to account for these interrelated phenomena. He inclines to the view that the sun emits at different times different wave lengths which are therefore more or less absorbed by the earth's atmosphere and cause the observed effects. Especially this modifies the action of the unipolar induction of electricity, and so causes disturbances of the state of equilibrium. An application of this process is made by comparing the harvests of Wasa

and Kuopie, 1810-'77, with the variations of the solar output, and the result shows that the former depends very closely upon the latter.

(6) The periodic terms in meteorology due to the rotation of the sun on its axis, F. H. Bigelow (pp. 500-510, Pls. XVI-XVIII).-This paper contains a brief summary of the variations in the several meteorological elements in the period of the sun's equatorial rotation. The action is ascribed to the polar magnetic field emitted by the sun falling upon the polar regions of the earth and along the magnetic meridians. A set of fifteen curves is appended which show, as is to be expected from this preliminary compilation of the material, a rough and yet unmistakable tendency to vary like the curve derived from the European magnetic field and like that of the sun spots along the solar meridians. These curves embrace the lows of the United States, the lows and highs of the North Atlantic, the weather at Bismarck, Chicago, Washington, and in Europe, European temperatures and relative humidity, atmos pheric electricity, thunderstorms of the United States, and the number of high and low centers in the Northern Hemisphere.

(7) Review of recent investigations into the subject of atmospheric elec tricity, J. Elster and H. Geitel (pp. 510-522).—A general review of the results of various investigators into the subject of atmospheric electricity is given. Particular attention is called to the important advances due to the invention of the electrometer by Sir W. Thomson and the reduction of the measures to absolute units; to the division of the observations by Exner into clear and cloudy weather phenomena; the gradual deduction of the laws of diurnal and annual variations by several investigators; the several theories to account for the existence of the electric potential fall in the atmosphere. Finally, the work of the authors in discussing the action of the ultraviolet light falling upon zinc surfaces and the consequent extension of the principles to the atmosphere is detailed. This is a very interesting and valuable summary of the knowledge of this science.

(8) On the construction of earth-magnetic instruments, M. T. Edelmann (pp. 522–539).—Under the general heading of station apparatus is given a description of the various forms of instruments that have been constructed for the measurement of the declination, horizontal force, and vertical force; that is, the declinometer, the inclinometer, the magnetometer, the magnetic variation apparatus, the magnetic intensimeter, the Lloyd balance, and the Lamont induction apparatus. Under the heading "Portable apparatus" is described the Wild portable theodolite, the combination for determination of declination, the combination for oscillation observations, the adaptation for deflection, and the arrangement for the determination of the inclination. A full series of diagrams accompanies the paper, which forms the most complete brief account of magnetic instruments accessible to the public.

(9) On some improvements in magnetic instruments, M. Eschenhagen (pp. 539-550).-The installation of the Magnetic Observatory at Potsdam has given the author the opportunity to put in practice several very important devices for increasing the sensitiveness and efficiency of the apparatus of a primary station. The details are minute and specific so as to be useful to other magneticians. The mode of setting the threads, the marks, the movements of the telescopes, the form of the magnet bars and mirrors, the collimation, the method of signals to comparison observations, the systematic scheme or order of observation, the best methods for suspension and the threads to be used, the length of the time scale, the mode proposed for exchanging traces of different observatories, the recording apparatus, and other interesting topics are included in this essay. The author's well-known success in this line of work and the excellent results obtained by him make the experiences here noted of great importance to the practical observer.

(10) The present condition of mathematical analysis as applied to terrestrial magnetism, A. Schuster (pp. 550-569, Pl. XIX).-This paper gives an account of the harmonic analysis, as applicable to terrestrial magnetism, in a brief summary. Gauss's method of obtaining the coefficients in the harmonic analysis of the magnetic potential is described and the constants as derived by Gauss, together with Petersen's revision of the same, are recounted. Neumann's abbreviated method for obtaining the coefficients is described, with a short criticism of the same. After this follows a discussion of the most suitable method to be adopted in future reductions, with the purpose of arriving at the solution of the problem of the secular variation of the terrestrial field. The paper concludes with a treatment of the diurnal variation, the data depending upon four stations. The relation of this problem to the solar and cosmical phenomena is indicated, and the essay, though condensed, is a very significant contribution to this fascinating subject.

(11) Methods and instruments of precision for the study of atmospheric electricity, A. B. Chauveau (pp. 569–583, Pls. XX-XXV).—An historical review of the different observations of atmospheric electricity, and the instruments used, is given, including the methods of observation, by the insulated conductor, by the method of Pelteer, the method of Volta, and the process of Sir W. Thomson. A detailed description of Mascart's register, collector, and electrometer is added, the abstract of the observations, and the details of a portable apparatus. The most important section of the paper gives an account of the method of measuring high potentials, as employed at the Central Meteorological Bureau, and the Eiffel Tower, Paris, and a set of curves is appended showing the variations of the field on the ground and on the tower. The accompanying weather notes enable the reader to judge of the prevailing atmospheric conditions. By this process observations at very different potentials can be recorded by the same self-registering apparatus.-F. H. BIGELOW.

Thunderstorm studies based on balloon voyages, L. SONUCKE (Abhandl. Bayer. Akad. Wiss., München, 1894, vol. 18, pp. 60).—This is an exhaustive study of 60 quarto pages upon the conditions in the free atmosphere favorable to the formation of thunderstorms, dwelling especially upon the conditions on June 19, 1889. The author indicates that for a stable equilibrium the temperature diminution with height must be less than 5.4° per 1,000 ft. This may be expected as long as there is no condensation of the vapor in the free air. If there is a greater temperature decrease the condition becomes unstable and there is occasion for rising air currents. Observations on the Sonnblick, 10,000 ft. high, are reported to confirm this statement. On this mountain, June 19 at 6 a. m., there were stratus clouds in the south, at 7 the sky was half covered, at 9 thunder heads, at 1 p. m. summit covered with clouds, at 4 rain began, and at 7 thunderstorm with snow. The observations showed that in the forenoon with a clouded sky there was a diminution of 5.4° per 1,000 ft. instead of the normal 3.9°.

Very full observations taken in the balloon "Herder" at Munich are given; also those taken in the "Nautilus" at Berlin. The "Herder" left the earth at 7.55 a. m., and rose in 4 hours to a height of 65,000 ft. The relative humidity ranged from 56 per cent at 2,280 ft. to 93 per cent at 3,540 ft. and dropped again to 63 per cent at 6,500 ft. The diminution of temperature with height was 1.60 per 1,000 ft. at 2,280 ft. at 8.20 o'clock, and at 11 o'clock at 3,600 ft. it was 5.8°.

At Berlin the balloon rose at 7.6 a. m. The diminution in temperature at 1,070 ft. was 1.80 per 1,000 ft.; at the highest point, 11,960 ft., it was 3.7° at 11 o'clock. At 1.35 the diminution was 6.8° at 3,790 ft., but this last value was due in part to the rapid descent of the balloon, which carried with it the lower temperature of the higher atmosphere, there having been a drop of 3,940 ft. in 5 minutes. The lower limit of the cloud formation as shown at some of the mountain stations was 4,920 to 5,250 ft. The "Herder" balloon passed into cumulus cloud at 5,460 ft. The "Nautilus" found dark clouds at 9.5 o'clock at 5,760 ft., and at 9.51 the clouds were at 6,350 ft.

At most of the stations the wind was light at 10 to 11 with a sudden change in direction about that time. In many cases there was a stoppage in the regular diurnal rise in temperature at about 10.30, due to cloudiness, probably. Freezing temperature was reached at 10,890 ft. and at 8,000 ft. in the "Nautilus" and "Herder," respectively. It was found that the stratum of 32° temperature was higher in the cloud than outside of it. A sinking of cirrus cloud to a lower level was noticed, and the evaporation of the ice crystals would tend to cool the air.

The thunderstorms occurred in the Alps at noon, but at the lower stations from 4 o'clock to 6. In the Alps the lowest pressure, highest relative humidity and temperature, and the highest clouds were at noon. According to the author's view, the abundance of high potential electricity is due to friction between water and ice particles at great