February 14, 1901] 



NATURE 



387 



Edinburgh. ' • 



Royal Society, January 21.— Lord Kelvin, President, in the 

 chair. — The Chairman communicated a paper on one-dimensional 

 illustrations of the kinetic theory of gases, in the course of which 

 he referred to Waterston's doctrine of the partition of energy 

 among molecules of different size, a doctrine which, although 

 supported by Maxwell, Bolizmann and others, he believed to be 

 not only not proved but not true. If the doctrine is found to 

 fail in one particular case, its universality is disproved. By con- 

 sidering the impacts among a row of hard elastic spheres con- 

 strained to move to and fro in the same straight line, he had, by 

 direct calculation of the effects of 300 successive collisions, found 

 no tendency towards a state in which the average energy of all 

 the masses was the same. When the time of impact was 

 assumed to be infinitely short, so that no more than two spheres 

 could be in contact at the same time, the calculation was simple 

 enough ; but the problem quite changed its character when the 

 time of impact was taken as finite, so that three or more particles 

 might be in contact at the same time. It was shown" that 

 impenetrability was not a necessary quality of molecules. If we 

 follow Boscovich and regard them as centres of force, then two 

 molecules might, on collision, simply pass through one another. 

 —Dr. Knott read the first part of a paper on solar radiation and 

 earth temperatures, in which a comparison was made between 

 two sets of data, the one derived from Langley's well-known 

 results, the other from a recent discussion by Dr. Buchan of 

 temperature observations made at various depths in the eastern 

 part of the Mediterranean Sea by the Austrian ship Pola. Xhese 

 seemed to indicate a daily see-saw of temperature in a stratum 

 of surface water 50 metres thick. It was difficult to credit direct 

 solar radiation with the power to penetrate so deep ; but the 

 difficulty was greatly increased when a simple calculation showed 

 that the afternoon excess of temperature which was indicated 

 meant art accumulation of 1460 units of heat under each square 

 centimetre of surface during eight hours of daily sunshine. For, 

 with Langley's value of the solar constant, it could be calculated 

 that the whole wlar energy supplied to each square centimetre 

 of the earth's surface in the latitude of the Mediterranean 

 during eight hours of the midsummer day did not exceed 750 

 units. This serious discrepancy seemed impossible of explana- 

 tion if the general accuracy of both sets of data was assumed. 

 —Dr. Thomas Muir communicated three papers, namely, note 

 on pairs of consecutive integers, the sum of whose squares is an 

 integral square ; the differentiation of a continuant ; and the 

 Hessian of a general determinant. By direct calculation of the 

 various elements, it was shown that the Hessian of the deter- 

 minant D of the «th order had the value +(« - i)D"("~'-^). 



Paris. 

 Academy of Sciences, February 4.— M. Fouque in the 

 chair.— Notice on M. Agardh, by M. Bornet.— On the origins 

 of chemical combination. The allotropic states of silver, by 

 M. Berthelot. The method employed is to measure the amount 

 of heat developed by the various allotropic modifications of silver 

 when dissolved in mercury. The five kinds of silver employed 

 gave for 108 grams of the metal amounts of heat varying between 

 o-o8 calorie and 2-03 calories. The values previously obtained 

 for the heats of combination of silver with other elements 

 depend, therefore, upon the state of the metal used, and hence 

 require a correction.— Studies on the combinations of silver with 

 mercury, by M. Berthelot. — On the isentropicstabiUty of a fluid, 

 by M. P. Duhem.— A simple apparatus for the application of 

 the phototherapic method of Finsen, by MM. Lortet and 

 Genoud. The rays from an arc lamp are concentrated by means 

 of a globular flask, through which cold water is kept running 

 The greater part of the heat is absorbed by the water in the 

 lens, and the apparatus has given good results in actual clinical 

 practice.— Remark on the subject of a note by M. S. Kantor 

 by M. F. Enriques.— On pencils which are transformed on two 

 sides into orthogonal pencils by the method of Laplace, by M. C. 

 Guichard.— On the density of the zeros and the maximum modu- 

 lus of a complete function, by M. Pierre Boutroux.— On the 

 relation between the solar activity and the diurnal variation of 

 the magnetic declination, by M. Alfred Angot. This problem 

 has been attacked by applying the method of Fourier to the 

 observations of Pans and Greenwich, the values for the constants 

 obtained in the two cases agreeing very well.— On the borates of 

 magnesium and the metals of the alkaline earths, by M L 

 Ouvrard. By heating to a dull red heat a mixture of magnesia, 

 boric anhydride and potassium h)drogen fluoride, the borate 

 NO. 1633. VOL. 63] 



B^Og.sMgO is obtained in a "w6ll crystallised state. The corre- 

 sponding compounds of birium, strontium and calcium were also 

 i.solated. — On the electrolysis of the oxy-acids Preparation of 

 5-amyloxypropionic acid and of the diamyline of hutanediol. by 

 M. I'abbej. Hamonet. To prevent the occurrence of secondary 

 reactions with the hydroxyl group, the hydrogen of this group 

 was replaced by an alkyl group, and the pita-sium salt of this 

 compound electrolysed. No satisfactory results were obtained 

 with o-oxy-acids, but with /8-oxy-acids the synthesis was smoothly 

 effected in the required direction. — On the saccharifying action 

 of wheat germs, and on their use in brewing, by M. Lindet. 

 Owing to the extensive use of roller milling, the germ of the 

 wheat is entirely separated from the farinaceou-; portion of the 

 grain. A comparative study of the action of wheat germs and 

 malt upon a solution of dextrinised starch showed that practically 

 the same, amount of sugar was produced in each case. In the 

 case where the wheat germs are employed, the distillery residues 

 will have a higher feeding value. — The legend of Lepas anatifera, 

 and oi Vallisneria spiralis, hy M. Frederic Houssay.— The 

 Rainy of Madagascar, by M. H. Jacob de Cordemoy. The 

 author identifies the /'a/;y/ of Madagascar with Canarimn multi- 

 floritm. This tree exudes a greenish-yellow resin which is 

 formed in the stem in resinous canals which are specially 

 developed in the liberian tissue. — On a new genus of fossil stem, 

 by M. B. Renault. The fragment of stem described was found 

 in a dolmen of Haute-Alsace. It is named Adelophyton julieri. 

 — On the presence of a layer of Devonian anthracite at Koui- 

 tcheou in China, by M. G. H. Monod The fossils found in the 

 coal-measures at Lan-mou-tchang, in Koui-tcheou, and in the 

 neighbouring strata show that these are clearly Devonian. This 

 field shows that the vertical extension of the coal in China is 

 greater than had been supposed, and this extension ought to be 

 still further increased. — The culture and reproduction of the 

 salmon {Salino salar) in fresh water, by M. Jousset de Bellesme. 

 The experiments described prove that the culture and reproduc- 

 tion of the salmon is possible in fresh water exclusively. This- 

 gives rise to the belief that although the habit of going to the 

 sea is favourable to its development, it is neither very ancient nor 

 absolutely necessary to its reproduction. — On the constitution of 

 the soil at great oceanic depths, by M. J. Thoulet. As a result 

 of the study of sixty specimens taken at various depths by the 

 Prince of Monaco, the views previously put forward by the author 

 are confirmed. — On a small laboratory furnace, by M. Albery 

 Bruno. 



St. Louis. 

 Academy of Science, December 17, 1900.— Dr. O. Wid- 

 mann read an account of the great St. Louis crow-roost, in which 

 were embodied many facts concerning the life-history and habits 

 of the common crow. — Prof F. E. Nipher gave an account of 

 some of his recent results in positive photography. He has now 

 found that hydrochinone baths of normal strength may be used. 

 The formula given in each box of Cramer plates yields good 

 results if the mixed bath is diluted with water to one-third 

 strength. The potassium bromide may be left out, and one drop 

 of concentrated hypo-solution must be added for each ounce of 

 diluted bath. The hypo has a most wonderful effect. With the 

 samebath, plates may be developed as positives in the dark room or 

 in direct sunlight. He had even started the developing of a plate 

 in a dark room, where it progressed very slowly, but very satis- 

 factorily ; continued the operation in diffused daylight in an ad- 

 joining room, and finished the operation in direct sunlight. The 

 process was accelerated by the light, but did not appear to be 

 otherwise changed by the change in illumination. The result- 

 ing picture could not be distinguished from those produced by. 

 ordinary methods. This picture was shown by means of the 

 lantern. A box of Cramer's "Crown," "Banner" or " Iso- 

 chromatic " plates may have the plates individually wrapped in 

 black paper, in the dark room or at night, and all the remaining 

 work may be done in the light. A plate is taken from its wrap- 

 ping into the lighted room and placed in the slide holder. 

 After exposure, it is taken out into the light and placed in the 

 developing bath, and the picture is then developed in the light, 

 and may be fixed in the light. Of course, during the changes 

 the p!ate should be shielded from the light as much as possible, 

 and the fixing bath may always be covered. But all of the 

 operations may be carried on without any dark-room con- 

 veniences that may not be secured even in the open fields.; 

 When weak hydrochinone baths are used, the picture, when 

 developed in strong lamp-light, or in sunlight, has at first a 

 golden yellow colour. When left in the lighted bath for an hour 



