complete devastation being to the right of the center seems to be plausibly explained when the agents of destruction are considered. On the right of the center there is the explosive action due to the reduced pressure on the outside of the buildings, the eastward component of the counter-clockwise wind of the tornado (probably over 400 miles per hour), the forward movement of the storm, and the west wind which was prevalent at that time all working in conjunction as agents of destruction; while on the left side of the center the westward component of the counter-clockwise wind is partially counterbalanced by the forward movement of the storm and the prevalent west wind. However, the backward or east wind of the storm was strong enough to move an eight room, one story house 41 feet to the westward, others shorter distances, to break elm trees 18 inches in diameter and to tip over a large percentage of the monuments in a cemetery in Mattoon. one Evidence of the explosive action so frequently stated as the principal agent in tornado destruction is not as general as would expect. The north ends and the east roofs were pulled from some houses in the partially demolished districts; plate glass windows were broken and had fallen out; in one of the churches and a store in which the glass was supported by metallic strips the windows were made convex; a pump and 14 feet of water was sucked from a well; these, and the various forms of roofing which were picked off like feathers from a fowl, indicate the suction action of the storm. Although examples of explosion are not common, it is ́quite probable that in and near the center of the storm explosion was a big factor in the preparation of buildings for the crushing action of the wind. Blunt cedar sticks were found imbedded one and one half inches in posts, and oatstraws one half inch in a maple tree. Another tree was decorated like an Indian's helmet with feathers. Huge oak and elm trees were twisted off, freight cars filled with brick were upset, as were also the tank cars of the Stan dard Oil Company. These and the buildings moved and crushed indicate the force of the wind of the storm. METEROLOGICAL CONDITIONS The Daily Weather Map, published at St. Louis at seven A.M. of the date of the storm, shows a well-defined cyclonic area covering most of the interior lowland of the United States. The isobars are oval in shape with their longest axis extending north and south. The isobars also show a slight bulging to the south in the southern quadrant. Cloudiness was prevalent over most of the Mississippi valley. At 11 A.M.1 a thunder shower occurred at Charleston. The clouds broke for a short time but lights were necessary at 2 P.M., and the air was exceedingly sultry and oppressive. At 3 P.M. a heavy, black, nimbus cloud appeared in the northwest, and frequent and fierce flashes of lightning occurred. Shortly before 3:45 a greenish black cumulo-nimbus cloud began to tumble in from the west. The wind suddenly changed from east to west through the south and hail began to fall. Then the hail lessened in amount and the wind attained a velocity of eighty miles per hour, the barometer dropped three tenths of an inch but came up immediately, and the temperature fell fourteen degrees. (Shown by the barograph and thermograph records.) Suddenly the wind lulled and flattened spheroidal hail, some having a major axis of 2 inches, fell until the ground was covered. The hail was accompanied and followed by a deluge of rain. Although the funnel or balloon-shaped cloud of the tornado was not visible to those in the cities, it was seen and well described by numerous individuals who were west of the cities and to the right or left of the storm. J. P. CAREY DEPARTMENT OF GEOGRAPHY, June 4, 1917 1 Observations made at the State Normal School, Charleston, one mile to the south of the storm track. SCIENTIFIC BOOKS Theoretical Chemistry. By WALTER NERNST. Trans. from revised seventh German edition by H. T. TIZARD. New York: The Macmillan Company, 1916. 22 X 15 cm.; pp. xix+853. Price, $5.00. This is a translation of the seventh German edition and as such is welcome. It would have been more welcome, however, if the publisher and the translator had been courageous enough and enterprising enough to have issued the volume some years ago. As it is, everything in the book is at least five years old and, in addition, the translator says: "The character of the work is slowly changing, since it is no longer possible in a book of this size to describe fully all the modern developments of theoretical chemistry. The new matter in this edition is therefore concerned mainly with Nernst's own researches. For example, there is a very interesting and clear account of the modern theory of solids, but, on the other hand, practically no mention of the recent advances in radio-activity and the atomic theory. These inevitable restrictions will hardly detract from the value of the book." This is certainly a very tactful way of saying that Nernst is not willing to take the trouble to revise any parts of the book except those dealing with his own researches. In spite of the impossibility of describing fully the modern developments the translator has induced Professor Tutton to bring up to date all sections in the book dealing with crystallography. In looking over a book like this, one is struck with passages which would have escaped notice three years ago. On p. 156 Nernst deduces that the osmotic pressure of a substance in mixed solvents follows the gas laws. He states that the resulting formula was verified satisfactorily by Roloff and then points out that the addition of potassium chloride to aqueous acetic acid may raise the partial pressure of the acetic acid. Most of us believe in some things which we know are not so; but it takes a special type of mind to claim that we have proved a thing in the same breath that we mention facts which disprove it. The case is not so striking on p. 707 where Nernst formulates the generalization that if two phases are in equilibrium with a third phase at a certain temperature with respect to a certain definite reaction, they are then in equilibrium with each other at the same temperature and with respect to the same temperature. This differs from the preceding case because no data are given to show the inaccuracy of the theorem. Nernst knows as well as anybody that an aqueous solution saturated with respect to sodium chloride is not in equilibrium with an alcoholic solution saturated with respect to sodium chloride at the same temperature; but the glamour of the phrase is. upon him and he does not analyze it to see that what he has said is not the same as that two things which are equal to the same thing are equal to each other, though it may sound like that. This curious mixture of keenness and self-delusion is no longer an isolated phenomenon. We now know that it is a national weakness. On p. 570 Nernst is quite willing to state that methyl orange is a basic indicator and that the acid function of methyl orange is unimportant as regards change of color; but he will not mention the fact that Ostwald holds an entirely different view. The people who read Ostwald's books also never learn that anybody questions the opposite view. It would be incompatible with the dignity of either to admit that he was wrong. Consequently the student who reads one set of text-books learns one group of facts as unquestioned, while he who reads another set of text-books learns another group of facts without any suspicion that these things are not accepted universally. Incidentally, it might be mentioned that Kahlenberg's name does not appear anywhere in the book and that there is no reference anywhere to any of the objections raised by Kahlenberg. While one may object seriously to the order in which the subject is presented and to the spirit in which the book is written, there is no gainsaying the fact that Nernst is an ex tremely able man and that his book contains a great deal of valuable information. The mere fact that it has been through seven German editions is proof in itself that people read it. There is a fine sound to the subdivisions of the book: the universal properties of matter; atom and molecule; the transformation of matter; the transformation of energy. What could be better than this? When a man sandwiches a chapter on colloidal solutions in between one on radioactivity and one on the absolute size of the molecules, one is almost tempted to forgive him for talking about the enormous molecular weights of substances in the colloidal state. In a great many chapters what Nernst has to say is very well worth while and of course it is not fair to read the parts on colloid chemistry, photochemistry, and flame spectra in the light of what one now knows. It is possibly the war, though I think not; but the whole tone of Nernst's book grates on one, perhaps more when it is presented in English than when one reads it in German. The contrast between this book and van't Hoff's Lectures is very striking. The translation is very much better done than has been the case in most of the previous English editions. Either the translator or the proofreader has been very careless, however, in regard to proper names, many of which are misspelled. WILDER D. BANCROFT CORNELL UNIVERSITY SPECIAL ARTICLES THE MEASUREMENT OF LIGHT IN SOME OF ITS MORE IMPORTANT PHYSIOLOG ICAL ASPECTS THE principal relations of light to organisms include the following phases of its action: 1. Photosynthesis, in which specialized protoplastic masses containing chlorophyll elaborate carbohydrates from carbon dioxide and water. The well-known absorption bands of chlorophyll in the red and in the blue are taken to indicate the portions of the spectrum concerned in this action. 2. Influence of illumination on transpiration and water content. It is probable that the red end of the spectrum chiefly furnishes the wave-lengths which cause changes in temperature, and variations in water loss. 3. Influence of illumination on the respiration and other metabolic processes in protoplasm as induced by the photolysis of substances important to the life of the organism. 4. Coagulatory, neutralizing or disintegrating action of light or toxic effect of products, especially of the shorter wave-lengths, on living matter as exemplified by the fatal effects of blue-violet rays on minute organisms. 5. Tropistic reactions, in which the position of the axes or of the entire body is changed in response to direction or intensity of the rays and with respect to special wave-lengths Various parts of the spectrum may be active in different organisms. 6. The indirect action of light on rate, course and amount of growth, together with morphogenic reactions. Such effects have not yet been analyzed to an extent which might furnish data for a rational discussion of the direct effects of light on growth. Indirect effects are recognizable. 7. Action of light on environic conditions exemplified in the ionization of the air by the shorter wave-lengths as described by Spoehr. Experimentation upon any of these subjects requires sources of light under good control, screens for transmitting special regions of the spectrum and methods of measurement of the relative intensity of the illumination falling on the organism. Sunlight may serve in some work when the requisite screens are available, but incandescent filaments, mercury and amalgam vapor arcs enclosed in glass or in quartz may be used as sources of light down to wave-lengths of .28 μ. Layers of liquid, pigments in gelatine and other perishable screens have served admirably in some demonstration and research work, but when long-continued exposures to intensities approaching those of normal sunlight are desired a durable screen is necessary. A series of formulæ for a number of glasses which would transmit various parts of the spectrum has been developed in the laboratory of a prominent firm of glass-makers. These may Heat-Absorbing: Absorbs most of infrared and 97 per cent. of heat of Nernst lampgives a pyrheliometer reading about half that of good window glass. Transmits 65 per cent. of incident white light. Formula of twenty other glasses are available by the use of which the regions of the spectrum noted above may be modified or different separations made. Desirable effects may also be obtained by combination of two screens. Thus for instance light passing through a yellow of the type described above and the heat absorbing glass loses all the spectrum except the yellow and a small part of the red. The only thoroughly reliable measurements of solar radiation available to the biologist are those made with the Angström and Abbot type of pyrheliometer which recorded the total normal insolation in heat units. However, in the blue-violet region of the spectrum, which is of especial interest to the biologist, this type of instrument is not sufficiently sensitive. It is therefore proposed to use the photo-electric cell as developed by Elster and Geitel. This instrument has the great advantages of extreme sensitiveness in the blue-violet region and ease of manipulation; it records immediate and directly proportional values, and can be used for extensive ranges of intensities. A comparison of the results to be obtained by the use of the two methods is afforded by the data given below. Direct sunlight at the These results show a total value of normal sunlight through uviol glass transmitting the entire spectrum not being widely different by the use of the two instruments, although the pyrheliometer values are derived from the longer wave-lengths and those of the sodium cell from the shorter ones. It may be assumed that half of the total energy registered by the pyrheliometer is strictly within the red, which causes but little action in the sodium cell. The pyrheliometer shows a total of nearly 54 per cent. of the energy of sunlight passing through the yellow screen which transmits from red to and including the blue-violet. Perhaps the most interesting results are those which are obtained by measurement of light passed through the so-called heat-absorbing screen, which has been found to transmit the visible spectrum except the longer red and infra-red. The pyrheliometer reading of such a glass is but 25 per cent. of clear sunlight, while the sodium cell records 63.2 per cent. of the total. A notable difference between the recording action of the two instruments in the blue is also evident. It is self-evident that the universal method of calibration of sunlight intensities by the pyrheliometer does not give results which are adequate or correct in all of the various aspects of the physiological effects of light. Measurement of light from artificial sources has been done chiefly by photometric methods, but it is to be pointed out that the results obtained in this manner are scarcely more adequate than those of the pyrheliometer. The sodium cell connected with a suitable portable galvanometer offers many advantages for the measurement of light intensities in natural habitats, and a comparison should be made between it and the various photometers and illuminometers which are now being recommended to the forestry student and the ecologist. It seems highly probable that more exact measurements in the blue-violet region so important in photolysis and phototropism will yield information by which some of the current discordant results may be harmonized. In any case the action of the photoelectric cell in light is more nearly parallel to that of the organism than that of any other light measuring instruments hitherto available. We are indebted to Professor Jacob Kunz, of the University of Illinois, who has very kindly constructed some cells to meet our particular needs and whose advice has been most helpful in the application of this instrument to physiological uses. DESERT LABORATORY, TUCSON, ARIZONA, March 30, 1917 D. T. MACDOUGAL, H. A. SPOEHR SOCIETIES AND ACADEMIES THE BIOLOGICAL SOCIETY OF WASHINGTON THE 569th regular meeting of the society was held in the Assembly Hall of the Cosmos Club, Saturday, April 7, 1917, called to order at 8 P.M. by President Hay with 45 persons in attendance. Under the heading brief notes and exhibition of specimens Dr. R. W. Shufeldt exhibited lantern slides of living California quail, calling attention to their rapidly diminishing numbers. Dr. L. O. Howard called attention to the cocoon of a Cecropia moth containing moon-stones that had lately come to his notice. He expressed the opinion that they had been placed there by a thieving crow or bluejay. Mr. A. Wetmore stated in this connection that he had seen bluejays insert small acorns and kernels of corn into large cocoons. The regular program consisted of two communications: A Note on the Hibernation of the Mud-turtle: ALEXANDER WETMORE AND FRANCIS HARPER. The authors reported finding a specimen of Kinosternon pennsylvanicum shortly after it had left its underground winter-quarters. The hole from which it had emerged was beneath a dense growth of green-briar in an old field and about fifty yards from the nearest marsh. The burrow was 9 inches deep, and was open save at the lower end, where the animal had apparently lain encased in a mass of mud. The actions and conditions of the turtle after being placed in water were described in detail, and an account of a postmortem examination of the viscera was given. Messrs. W. P. Hay, M. W. Lyon, Jr., and Wm. Palmer took part in the discussion. Botanizing in the Hawaiian Islands: A. S. HITCH соск. The speaker visited the Hawaiian Islands during five months of 1917. He said the trade winds deposit their moisture upon the eastern and northern mountains of all the islands, furnishing the conditions for rain forests in these regions. The lee side of the islands is dry even to aridity. An interesting feature of the wet areas at or near the summit of the ridges are the open bogs. These bogs are devoid of trees and large shrubs, but contain a variety of low shrubs and herbaceous plants. Many species form tussocks, or hemispherical masses raised above the level of the bog. The most conspicuous of the tussocks is made by a sedge (Oreobolus furcatus Mann.). Three peculiar species of Panicum are tussock-formers (Panicum monticola Hillebr., P. imbricatum Hillebr. and P. isachnoides Munro). Owing to the extreme isolation of the islands the flora is peculiar and interesting. The family Lobeliaceæ is represented by about 100 species, belonging to about 6 genera. Many species are arboreous, forming trunks ten to twenty feet, or in a few cases as much as forty feet high. The crown of foliage gives the aspect of a palm. The grasses, disregarding the introduced species, are not numerous, but several are peculiar. The genus Eragrostis is represented by numerous species. A rare species of Poa (Poa siphonoglossa Hack.) produces leafless rushlike stems, as much as fifteen feet long. His talk was illustrated by maps, botanical specimens and numerous lantern-slide views of various features of the islands. M. W. LYON, JR., Recording Secretary |