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physiological means. During the four days and three nights of the test they were engaged, as far as possible, in their usual occupations; their meals were of the customary kind, and were taken at the ordinary times, with the addition of a light lunch at about midnight. At intervals of six hours a series of tests was made on each subject, to determine his mental and physical condition. To eliminate the effects of practice, these tests were begun three days before the experiment. The test of the first day of experiment, before any loss of sleep had actually occurred, represent the normal condition of the subject. Tests were also made after the night's sleep that followed the conclusion of the experiment. One of the writers was the first subject. The two other subjects were instructors in the university; the latter were experimented upon at the same time.

Some of the results are of special interest. The reaction time (for sound) showed a gradual increase for two of the subjects, which was masked in the third case by increase of practice; at one period (different in the three cases) the time was considerably greater than earlier or later in the experiment; the mean variation was somewhat above the normal, but not remarkably great. The acuteness of vision, measured by the distance at which a page of print could be distinguished and read, actually increased during the progress of the experiment, and fell off again after the ensuing sleep. The memory test of the two last subjects consisted in committing random series of figures; the time required for this memorizing fluctuated considerably, with a marked lengthening towards the close of the experiment. One of the subjects was unable to memorize the figures at all at two of the last day's tests; he found it impossible to bold the attention upon the task long enough to complete it. The time consumed in adding sets of figures was fairly constant, with two or three exceptions; it was apparently independent of the memory conditions. Voluntary motor ability," tested by the number of taps that could be made with the finger in five seconds, showed no marked alterations ; neither did the susceptibility to fatigue, as tested by continuing this tapping for sixty seconds. The strength of grip, measured on the squeeze dynamometer, fell off from 20 to 30 per cent. at the end of the second day, but afterwards recovered-in two cases fully, in the other partially. The weight of the men remained fairly constant, showing a slight increase towards the close of the period, and the variation of the pulse was within the normal range of daily fluctuations.

The first subject suffered from marked visual hallucinations after the second night. "The subject complained that the floor was covered with a greasy-looking, molecular layer of rapidly moving or oscillating particles. Often this layer was a foot above the floor and parallel with it, and caused the subject trouble in walking, as he would try to step up on it. Later the air was full of these dancing particles, which developed into swarms of little bodies like gnats, but colored red, purple or black. The subject would climb upon a chair to brush them from about the gas jet, or stealthily try to touch an imaginary fly on the table with his finger. These phenomena did not move with movements of the eye and appeared to be true hallucinations, centrally caused, but due no doubt to the long and unusual strain put upon the eyes. Meanwhile the subject's sharpness of vision was not impaired. At no other time has he bad hallucinations of sight, and they entirely disappeared after sleep." Neither of the other subjects experienced these hallucinations.

At the close of the experiment the subjects were allowed to sleep as long as they desired. Tests were made upon the first subject, however, at hourly intervals during the first night, to determine the depth of his sleep. He awoke naturally after ten and a half hours, and remained awake during the rest of the day, but slept two hours more than bis normal amount the second night. Of the other subjects, one awoke of his own accord after eleven, the other after fourteen hours' sleep; both felt quite refreshed; they required no extra sleep the next night, and felt no ill effects from the experiment.

It will be noticed that the sleep made up was but a small proportion of the amount lost, viz., 16, 25 and 35 per cent in the three cases respectively. Two possible explanations for this are offered : either a greater depth of sleep may make up for a lesser duration; or sleep is a relative phenomenon, and the subjects, while apparently awake, were in reality partially asleep at times during the experiment. The authors believe that both of these facts are true, and that they operated together in the present instance. While the subjects were not allowed to go to sleep for an instant, and the slightest tendency to close the eyes was met by active measures, still there were indications of the presence of dreams, in lapses of memory and occasional irrelevant remarks. “It must be understood,” say the writers, “that these dreams were instantaneous and the subject as wide awake as he could be kept; but these facts reveal a cerebral condition related to sleep. This hypothesis alone, however, would not seen to account fully for the small proportion of sleep made up. And, indeed, a study of our special tests shows that restoration took place chiefly during the profound sleep following the sleep fast, and took place rapidly. That this sleep was actually more profound, and that the profound part of it was longer than usual, was shown by our experiments in depth of sleep,” on one of the subjects.

The authors think it would have been possible to prolong the experiment beyond the ninety hours without danger, except in one of the

These results contrast favorably with those obtained by M. de Manacéine upon young dogs. The animals were kept from sleeping and died at the end of the fourth or fifth day.--H.C. Warren.

three cases.

PROCEEDINGS OF SCIENTIFIC SOCIETIES.

American Philosophical Society.–November 6, 1896-—The following communications were made : “Recent Archæological Explorations on the Shell Keys and Gulf Coast of Florida,” by Frank Hamilton Cushing, followed by Dr. D. G. Brinton and Prof. F. W. Putnam.

November 20, 1896.-Prof. H. V. Hilprecht addressed the Society on bis recent archæological discoveries at Nippur, and exhibited a collection of tablets with Summerian inscriptions. A paper on "A New Physical Property of the X-Ray,” by Charles L. Leonard, M. D., was read.

University of Pennsylvania, Biological CLUB.-November 2, 1896.-The following demonstrations were made; Descriptive Exhibitive of Streptocarpus and Ephedra by Dr. J. M. McFarlane and of Botrychium by H. C. Porter. The following communication was made ; School Museums, by Mrs. L. L. W. Wilson.

H. C. PORTER, Secretary. The Biological Society of Washington.-The following communications were made; Theodore Gill, “ The Category of Family or Order in Biology;" C. Hart Merriam, “Notes on the Fauna of Oregon;" E. A. DeSchweinitz, “Some Methods of Generating Formaldehyde, and its Use as a Disinfectant;" C. Hart Merriam, "Supplementary Notes on Tropical American Shrews.

November 21st.—The following communications were made : G. H. Hicks, “ The ‘Mildews' (Erysipheæ) of Michigan;" Frederick V. Coville, “ The In florescence of the Juncaceæ;" Theodor Holm, "The Alpine Flora of Pikes Peak and Grays Peak in Colorado ;” C. L. Pollard, “ Some Further Remarks on Briton and Brown's Illustrated Flora.”

FREDERIC A. LUCAS, Secretary.

National Academy of Sciences.—A scientific session of the Academy was held in New York, at the Columbia University, beginning November 17, 1896, at 11 o'clock, A. M.

The following papers were read: “On Certain Positive Negative Laws in their Relation to Organic Chemistry," A. Michael ; " The Jurassic Formation on the Atlantic Coast," 0. C. Marsh; "The Hydrolysis of Acid Amides," Ira Remsen ; “ The Isomeric Chlo. rides of Paranitroorthosulphobenzoic Acid,” Ira Remsen; “The Equations of the Forces Acting in the Flotation of Disks and Rings of Metal, with Experiments Showing the Floating of Loaded Disks and Rings of Metal on Water and on Other Liquids,” Alfred M. Mayer; “On the Geographical Distribution of Batrachia and Reptilia in the Medicolumbian Region," E. D. Cope; “On the Solar Motion as a Gauge of Stellar Distances," S. Newcome; “Memoir of F. B. Meek,” C. A. White; “The Evolution and Pylogeny of Gastropod Mollusca," A. E. Verrill; “On Flicker Photometers," 0. N. Rood; “A New Type of Telescope Free from Secondary Color,” C. S. Hastings; “A Graphical Method of Logic,” C. Pearce ; “On Mathematical Infinity," C. Pearce.

A reception was given to the Academy by Mrs. Henry Draper, on the evening of Wednesday, November 18.

Boston Society of Natural History.-November 4th. The following paper was read : Prof. George Lincoln Goodale, “ The Reclaiming of Deserts."

November 18th. The following papers were read: Prof. George H. Barton, "Observations upon the Inland Ice and the Glaciers Proceeding from it in the Umanak District, Greenland ;” Prof. Alfred E. Burton, “The Topographical Features of the Umanak District, Greenland. Other members of the Greenland Expedition were present, and took part in the discussion.—SAMUEL HENSHAW, Secretary.

The Academy of Science of St. Louis.-At the meeting of November 2, 1896, Mr. Colton Russell spoke of “What an Entomologist Can Find of Interest About St. Louis,” illustrating his remarks by numerous pinned specimens of insects, giving particular attention to the butterflies, and speaking at some length of the phenomena of periodicity, migration, polymorphism, etc., as illustrated by these insects, his paper embodying the result of a large amount of field work performed during the last ten years. Resolutions were adopted opposing the passage of the antivivisection bill now before the United States Senate. Three persons were elected to active membership.

At the meeting on the evening of November 16, 1896, Dr. Charles R. Keyes, the State Geologist of Missouri, read a paper entitled, “How Shall We Subdivide the Carboniferous ?” and Professor J. H. Kinealy exhibited a chart for determining the number of square feet of lowpressure steam-heating surface required to keep a room at 70° F., and gave a description of the method of making the chart. Two active members and one life-member of the Academy were elected.

WILLIAM TRELEASE, Recording Secretary. New York Academy of Sciences.—November 9th.—Members of the Columbia University Expedition to Puget Sound made reports on the summer's work.

Mr. N. R. Harrington gave a short narrative of the expedition, including a description of the equipment of the laboratory, dredging, investigation and plankton collection.

In addition, he made a report on the Echinoderms, Crustacea and Annelids. Mention was made of the relation of the asymmetry in Scutella excentrica to its habit of burrowing and its vertical position in the sand. Abundant material, both larval and adult, of Entoconcha was obtained. This mollusk had been noted by Müller in 1852, and Baur in 1864, in Synapta digitata and by Semper in Holothuria edulis. The present material was found in an undetermined species of Holothuria. About forty species each of Crustacea, Annelids and Echinoderms have been identified.

Mr. Bradney B. Griffin presented the following report on the Platodes, Nemerteans and Mollusks:

The Platodes and Gephyrea are relatively scarce. They are represented solely by two Dendrocoels, and one Phymosoma respectively. The nemertines occur very abundantly, fully fifteen different species were obtained, most of which appear to be undescribed, though some seem to approach more or less closely the European forms rather than those of the east coast of America. The European species are the more numerous.

The Molluscan fauna is very rich and varied, ninety-three species of sixty-nine genera were collected. These include among others the large Cryptochiton stellerii which, when alive and expanded measures over 20 cm., besides numerous smaller species of Mopalia, Katherina, Tonicella, etc., that occur in vast numbers on rocks and piles between tides. The Nudibranchs are notable from their bright colors and large size. One species of Dendronotus attains a length of over 25 cm. Cages of color variation (Cardium and Acmaea) and color series (Littorina) were to be met with, as well as color harmonization; many

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