photographic method of comparing the rate of vibration of two tuning forks. The forks are so clamped that a prong of each is held in front of a manometric capsule. The forks are bowed and the flames photographed as described in the Physical Review, Vol. II., p. 305, 1875. The vibrations are then counted in the wavy line on the negative. The accuracy in ordinary work is about two or three-tenths of a wave per second.

The second paper was by Prof. J. K. Rees on the Penumbra of sun-spots as shown in Rutherfurd's photographs, with especial reference to the discussion at the December meeting of the Royal Astronomical Society. Professor Rees called the attention of the Section to the remarks made by the Rev. F. Howlett on presenting to the Royal Astronomical Society of London three volumes of sun-spot drawings. This set of volumes contains drawings made during a period of thirty-five years, and shows minute details in regard to the forms and changes of solar spots. The Rev. Mr. Howlett stated that his main object in continuing the series had been to test the theory put forth by Professor Wilson, of Glasgow, in the latter part of the last century. Wilson's theory claimed that the penumbra in a spot shelves down toward the umbra; and that the portion of the penumbra nearest the sun's centre will, therefore, grow narrower and narrower, due to perspective, as the sun-spot reaches a point nearer and nearer to the limb. Mr. Howlett claimed that his drawings showed that the Wilsonian theory was not borne out by his observations as recorded in his drawings.

He made bold to say that, instead of the penumbra of the spot possessing shelving sides sloping down toward the umbra, the penumbra shows a convex surface in a curve conformable to the general contour of the solar surface. He remarked that he had not himself witnessed a single case of certain notching of the limb.

Professor Rees exhibited on the screen a series of fine photographs of the solar surface taken by Mr. Rutherfurd with his photographic telescope (13 inches diameter of object glass, 11 feet of focal length) during the years 1870-1871. Attention was called to the appearance of the penumbral regions of the spots which showed conclusively that the penumbra was, as a rule, eccentric with respect to the umbra. Spots were pointed out near the centre of the sun where the penumbral marking was deficient on, sometimes the west side, then on the east side, sometimes on the north side and sometimes on the south side. Spots were also indicated which showed, when near the limb of the sun, the penumbral region wanting on the side farthest from the centre and well developed on the side toward the centre. So far as these photographs showed, there was no doubt that the Wilson theory did not completely explain the various phenom

ena.

Professor Rees also showed some pictures of sun-spots taken by Mr. C. A. Post, of New York City, exhibiting the non-central character of the umbra with respect to the penumbra. Mr. C. A. Post, of New York City, then threw on the screen some photographs of the sun and moon that he had taken.

He also exhibited a series of strikingly beautiful lantern slides made from photographs of lightning flashes.

Professor M. I. Pupin described his new form of automatic vacuum-pump (see Am. Journ. Sci., Vol. 39, 1895, p. 19). An extremely ingenious device utilizes an ordinary vacuum pump (water pump) to raise mercury for the Sprengel pump. Little mercury is needed and the whole is continuous in its action.

INDIANA ACADEMY OF SCIENCE.

The Indiana Academy of Science met at Indianapolis, December 27-28, 1894, with W. A. Noyes, of the Rose Polytechnic of

Terre Haute, as President, and C. A. Waldo, of De Pauw University, as Secretary.

The Academy was well attended by the leading scientists of the State.

After the ordinary preliminary business, the body continued in general session, and listened to the reading of nine papers on general scientific topics.

The Academy then met in two sections, Physico-Chemical and Biological. In the former section, 28 short papers were read, and in the latter 51. The papers indicated that much work had been done during the past year in the various lines of scientific investigation.

The reports from the directors of the Biological Survey of Indiana were encouraging, showing that every effort was being put forth to accomplish this survey as quickly as possible and in a satisfactory manner. A resolution was passed requesting the Legislature of the State to print and distribute the proceedings of the Academy. This expense has always been borne by the Academy, but in view of the fact that the State is reaping the benefits it should assume the expense.

The Spring meeting will be held at the Wyandotte Cave, in Crawford county.

Following is a list of the papers: Address by the Retiring President,-Lavoisier. W. A. NOYES.

GENERAL SUBJECTS.

1. Some Facts in Distribution of Gleditschia Triacanthos and Other Trees: Ernest Walker. 2. Propagation and Protection of Game and Fish: I. W. Sharp.

3. Anthropology; the Study of Man: Amos W. Butler.

4. A New Biological Station and its Aim: C. H. Eigenmann.

7. The Surdue Engineering Laboratory since the Restoration: Wm. F. M. Goss.

8. Method of Determining Sewage Pollution of Rivers: Chas. C. Brown.

9. Psychological Laboratory of Indiana University: W. L. Bryan.

PHYSICO-CHEMICAL SUBJECTS.

10. Interesting Deposit of Alumina Oxyhydrate: G. W. Benton. 11. Observations on Glacial Drift of Jasper County: A. H. Purdue.

12. Concerning a Burial Mound Recently Opened in Randolph County: Joseph Moore. 13. Reversal of Current in the Toepler Holtz Electrical Machine: J. L. Campbell.

14. A Florida Shell Mound: U. F. Glick. 15. Note on Rock Flexure: E. M. Kindle. 16. The Alternate-Current Transformer with Condenser in one or both Circuits: Thomas Gray.

17. Elastic Fatigue of Wires: C. Leo Mees. 18. A Warped Surface of Universal Elliptic Eccentricity: C. A. Waldo.

19. Accurate Measurements of Surface Tension: A. L. Foley.

20. Effect of the Gaseous Medium on the Electrochemical Equivalent of Metals: C.

Leo Mees.

21. Some new Laboratory Appliances in Chemistry H. A Huston.

22. Volumetric Determination of Phosphorus in Steel W. A. Noyes and J. S. Royse. 23. Action of Ammonia upon Dextrose: W. E. Stone.

24. Action of Zinc Ethyl on Ferric Chloride and Ferric Bromide: H.H. Ballard.

25. The Sugar of the Century Plant: W. E. Stone and Dumont Lotz.

26. Camphoric Acid: W. A. Noyes. 27. Action of Potassium Sulfhydrate upon Certain Aromatic Chlorides: Walter Jones

G. A. Talbert.

6. Does High Tension of Electric Current Destroy Life: J. L. Campbell.

28. A New Phosphate: H. A. Huston. 29. Dip of the Keokuk Rocks at Bloomington, Ind: Edward M. Kindle.

30. Structural Geologic Work of J. H. Means in Arkansas: J. C. Branner.

31. Wave Marks on Cincinnati Limestone : W. P. Shannon.

32. Correlation of Silurian Sections in Eastern Indiana: V. F. Marsters and E. M. Kindle.

33. Some New Indian Fossils: C. E. Newlin. 34. Extinct Fauna of Lake County: T. H. Ball.

35. Strepomatide of the Falls of the Ohio, with their Synonymy: R. Ellsworth Call.

36. Streams of Southeastern Indiana, with List: H. M. Stoops.

37. The Swamps of Franklin County: H. M. Stoops.

BIOLOGICAL SUBJECTS.

38. Water Cultures of Indigenous Plants: D. T. MacDougal.

39. Working Shelves for Botanical Laboratory: Katherine E. Golden.

51. The Batrachians and Reptiles of Wabash County: W. O. Wallace.

52. On the Occurrence of the Whistling Swan (Olor columbianus) in Wabash County: A. B. Ulrey.

53. Birds of Wabash County: A. B. Ulrey and W. O. Wallace.

54. Birds Observed in the Sawtooth Mountains: B. W. Evermann and J. T. Scovell.

55. Animal Parasites Collected in the State

during the year 1894: A. W. Bitting.

56. Angling in the St. Lawrence and Lake Ontario Barton W. Evermann.

57. Indiana Mammals: Amos W. Butler. 58. Mimicry in Fishes: W. J. Moenkhaus. 59. Variation in Leuciscus: C. H. Eigen

mann.

60. The Redfish of the Idaho Lakes: B. W. Evermann and J. T. Scovell.

61. Observations upon Some Oklahoma Plants: E. W. Olive.

62. Rediscovery of Hoy's White Fish or

Evermann.

63. Saxifragacea of Indiana: Stanley Coul

ter.

64. The Range of the Blue Ash: W. P. Shannon.

65. Plant Products of the U. S. Pharmacopoa (1890): John S. Wright.

66. Noteworthy Indiana Phanerogams: Stanley Coulter.

67. Methods of Infiltrating and Staining in oto the Heads of Vernonia: E. H. Heacock.

68. Embryology of the Ranunculacea: D. M. Mottier.

69. Certain Chemical Features in the Seeds

W. S. Blatchley.

48. Preliminary List of Birds of Brown County: Edward M. Kindle.

49. The Birds of 1893: Amos W. Butler. 50. Some Notes on the Blind Animals of Mammoth Cave, with Exhibition of Specimens: R. Ellsworth Call.

Alida M. Cunningham.

70. Root System of Pogonia: M. B. Thomas. 71. Salt-rising Bread: Katherine E.

Golden.

72. An Increasing Pear Disease in Indiana: L. M. Underwood.

73. Notes on the Floridea: Geo. W. Martin.

74. Measurement of Strains Induced in Plant Curvatures: D. T. MacDougal.

75. The Stomates of Cyas: Edgar W. Olive. 76. The Buckeye Canoe of 1840: W. P. Shannon.

manium: H. A. ROWLAND and R. R. TATNALL.

Comparison of Photometric Magnitudes of the Stars: EDWARD C. PICKERING.

The Spectrum of Cephei: A. BELOPOLSKY.

78. Cell Structure of Cyanophyceœ: Geo. W. Martin.

79. Some Notes on the Amoeba: A. J. Bigney.

80. Variations of the Polyporus lucidus: L. M. Underwood.

81. Preliminary Account of the Development of Etheostoma Ceruleum: A. B. Ulrey.

82. Embryology of the Cupuliferæ: D. W. Mottier.

83. Embryology of the Frog: A. J. Bigney. 84. Variation in Etheostoma: W. J. Moenkhaus.

85. Blood Corpuscles of very Young Human Embryo D. W. Dennis.

86. Poisonous Influences of some Species of Cypripedium: D. T. MacDougal.

87. Development of Sexual Organs of Cymatogaster C. H. Eigenmann.

88. The Vegetation House as an Aid in Research J. C. Arthur.

:

89. The Proposed New Systematic Botany of North America: L. M. Underwood.

SCIENTIFIC JOURNALS.

ASTROPHYSICAL JOURNAL, FEB.

On a Lens for Adapting a Visually Corrected Refracting Telescope to Photographic Observations with the Spectroscope: JAMES E. KEELER.

Schmidt's Theory of the Sun: E. J. WILCZYN

SKI.

A Cloud-Like Spot on the Terminator of Mars: A. E. DOUGLASS.

Preliminary Table of Solar Spectrum WaveLengths. II.: H. A. ROWLAND. Photographic Observations of Eclipses of Jupiter's Satellites: WILLARD P. GERRISH.

The Arc-Spectra of the Elements. II. Ger

Publications.

NEW BOOKS.

Butterflies and Moths. W. FURNEAUX. London and New York, Longmans, Green & Co. 1894. Pp. xiv+358. $3.50 Elements of Astronomy. GEORGE W. PARKER. London and New York, Longmans, Green & Co. 1894. Pp. 236. $1.75. Steam and the Marine Steam-Engine. JOHN LEO. London and New York, Macmillan & Co. 1894. Pp. xiv÷196. $2.50. Memoir of Sir Andrew Crombie Ramsay. SIR ARCHIBALD GEIKIE. London and New

York, Macmillan & Co. 1895. Pp. x+397. $4.00.

Meteorology. THOMAS RUSSELL. London and New York, Macmillan & Co. 1895. Pp. xxiii+277. $4.00.

The Supremacy of the Spiritual. EDWARD RANDALL KNOWLES. Arena Publishing Co. 1895. Pp. 61.

The International Beginning of the Congo Free State. JESSIE SIDDALL REEVES. Baltimore, Johns Hopkins University Press. 1894. Pp. 106.

Report of work of the Agricultural Experiment Stations of the University of California; Being a Part of the Report of the Regents of the University. Sacramento, 1894. Pp. 506. The Cause of Warm and Frigid Periods. C. A. M. TABER. Boston, Ellis. 1894. Pp. 80. Electrical Engineering for Electric Light Artisans and Students. W. SLINGS and A. BROOKER. London and New York, Longmans, Green & Co. New and Revised Edition. 1895. 8°, pp. vii+753.

346 illustrations.