620 



NA TURE 



[April so, 1885 



of the pressure points were found to correspond with those in 

 respect of the temperature-points both as regards their distribu- 

 tion and the mode of their specific activity. The localisa- 

 tion of the sensation of pressure was still finer than that of the 

 sense of temperature. The smallest distance at which two 

 neighbouring points of pressure could be recognised as distinct 

 amounted to O'l mm. For the sense of pressure, therefore, just 

 as much as for the sense of cold and warmth, the existence of 

 specific nerve terminal apparatuses provided with specific ener- 

 gies was demonstrated. In reference to the sensation of pain, 

 Dr. Goldscheider was of opinion that no special nerves were to 

 be assumed. On the other hand, he thought that between the 

 cold, warm, and pressure-points lay the terminal apparatuses of 

 those nerves of feeling which produced specially the sensations of 

 touch. — Dr. Tichomirow reported first on earlier morphologic 

 investigations he had made into the embryological development 

 of Bombyx won', and brought out specially his observations on 

 the process of segmentation of the Bombyx ovum, on the first 

 development of the heart, and on the occurrence of an inner 

 skeleton in the head of this insect. He then passed to the 

 chemical examination of the ova of the Bombyx, which he had 

 just finished in the chemical division of the Physiological Insti- 

 tute. The weight of the ova was not a constant quantity, 100 ova 

 giving weights ranging from '02 to "06 gr. The firm membrane of 

 the ova had hitherto been universally regarded as consisting of 

 chitin. The easy solution, however, of this membrane in solu- 

 tion of potash proved the inaccuracy of this assumption. It 

 consisted, on the contrary, of a peculiar substance distinguish- 

 able from chitin, not only by its ready solubility in potash, but 

 also by a perceptible ingredient of sulphur. Chemically, this 

 substance had most relation to keratin, yet it contained less 

 carbon than the latter, and had therefore received a special 

 name, " cliorionin." A comparison of the chemical composition 

 of winter ova which had undergone but a partial transformation 

 with the Bombyx ova developed into caterpillars, showed that 

 in the latter the dry weight had suffered a little diminution, and 

 that the high glycogenous contents of the undeveloped eggs had 

 almost entirely disappeared in the process of development, but, 

 on the other hand, that chitin, which was wanting in the ova, 

 was present in perceptible quantities in the caterpillars ; while 

 the nitrogenous bases (nuclein, probably) were also present in 

 greater quantity in the developed ova than in the undeveloped 

 winter ova. 



Meteorological Society, April 7. — Prof. Fischer spoke on 

 metallic thermometers, and described the different kind; of 

 thermographs which had been constructed for the measurement 

 of temperatures by the expansion of the metals for meteoro- 

 logical purposes. At first only one metal was used, either in 

 the form of a long pole fastened at one end and bearing a 

 permanent register of temperatures attached to the other free 

 end, or several pieces of metal were joined together in the form 

 of a lever, to increase the thermal expansion. Later on, 

 two or three metals in the form of plates were bound together, 

 and the difference in the expansions of the different metals was 

 employed as a measure of the temperature. Thermographs of 

 this kind, composed of different metals, were still in use, espe- 

 cially in Switzerland. Several years ago Prof. Fischer had 

 instituted an investigation for geodetic purposes into the rate of 

 movement with which metals followed the atmospheric varia- 

 tions of temperature. The experiments were carried out with 

 two metal points of a base instrument, and their temperatures 

 measured with thermo-electric elements. The result of the 

 experiment was that on a rise of atmospheric temperature the 

 temperature of the metal was found to be constantly lower than 

 that of the air, whereas under a fall of atmospheric temperature 

 the temperature of the metal was warmer than that of the air. 

 These differences were all the greater the greater was the varia- 

 tion of temperature, and especially when the change of tempera- 

 ture occurred rapidly. In consequence of these results, Dr. 

 Matirer, of Zurich, had instituted more thorough comparisons 

 between the readings of the metallic and quicksilver thermome- 

 ters, and had arrived at results not only completely confirming 

 those of the speaker, but further demonstrating that the differ- 

 ences between the registrations of the metallic and mercurial 

 thermometers did not remain the same at all times, thus 

 showing that the former were not to be relied on for meteoro- 

 logical observations. — Dr. Hellmann discussed a proposal for 

 an inquiry into the requirements for correctly ascertaining 

 the rainfall over a particular district or region. In order to 



determine how close ought to be the network of stations of 

 observation in the lowlying plain of North Germany for the pur- 

 pose of obtaining an accurate representation of the distribution 

 of rain there, he proposed the erection of twelve rain-gauge 

 stations over an area of about thirty-seven square kilometres, 

 to be provided with similar rain-gauges, at which observations 

 should continue to be taken for a number of years. One year's, 

 and, still better, several years' observations would suffice to 

 show what was the minimum of rain-stations necessary for the 

 plain. The Society adopted the proposal, and empowered the 

 Committee to carry it out. — Prof. Bernstein laid before the 

 S ociety three barometric curves traced by self-registering baro- 

 graphs at three different points of the town on March 10. All 

 three showed distinctly a fitful rising of the pressure — at the 

 station situated most to the north at 3h. 28m. in the morning, at 

 that situated south-south-east from the previous one at 3(1. 40m., 

 and at that to the south-east at 3I1. 42m. From these exactly 

 determined points of time and the distances of the three places, 

 which were ascertained with equal precision, Prof. Bornstein 

 calculated the velocity of propagation of the squall-like atmo- 

 spheric impulse at 4 metres per second, the breadth of the wave- 

 front at about 2900 metres, and the depth of the squall at 962 

 metres. From this observation it appeared how desirable it 

 was for the study of atmospheric currents to have many baro- 

 graphs set up at stations situated near each other. 



[In the report of the Berlin Physical Society, March 20 

 (Nature, vol. xxxi. p. 596, line 29, 2nd column), for sulphates 

 of iron, read salts of iron.] 



Stockholm 

 Academy of Sciences, April 15. — Prof. C. Malmsten com- 

 municated the results of some researches by himself on the 

 theory of numbers. — Prof. Edlund gave a demonstration of 

 the incorrectness of the now prevalent theory on unipolar induc- 

 tion. — Prof. Gylden presented a paper by Herr K. Bohlin on 

 the element of the orbit of the third moon of Saturn (Tethys). 

 — The Secretary presented a paper by Prof. G. Dillner on the 

 inversion of an algebraic integral as the expression for the radix 

 of an algebraic equation, part 2. 



CONTENTS page 



The Fossil Mammalia in the British Museum . . 597 



The Self-Instructor in Navigation 59S 



Letters to the Editor : — 



On the Cause of the Dissimilarity between the Faunas 

 of the Mediterranean and Red Seas. — Prof. 



Edward Hull, F.R.S 599 



Hybridization among Salmonidre. — Francis Day . 599 



Forms of Leaves. — R. A. Rolfe 600 



Kite-Wire Suspended Anemometer Readings. — E. 



Douglas Archibald 600 



Temperature of the Body of Monotremata. — Dr. N. 



de Miklouho-Maclay 600 



Quinquefoliate Strawberry. — J. Lovell 601 



Some of the Meteorological Results of the Total 



Solar Eclipse of May 6, 1883 601 



Sir William Thomson on Molecular Dynamics, III. 



By Prof. George Forbes 601 



The Semaphore and Electric Light at Shanghai. 



(Illustrated) 603 



Variable Stars 604 



The Late Earl of Selkirk 606 



Roraima. (Illustrated) 607 



Notes 610 



Our Astronomical Column : — 



Occultation of Aldebaran on May 15 612 



Variable Stars 612 



The Double-Star 7 Equulei 612 



Astronomical Phenomena for the Week 1885, 



May 3-9 612 



Geographical Notes 613 



Further Notes on the Geology of Palestine, with a 

 Consideration of the Jordan Valley Scheme. By 



W. H. Hudlestone, F.R.S 614 



Chinese Insect-White Wax 615 



University and Educational Intelligence 616 



Societies and Academies 617 



