NA TURE 



\_Dec. 13, 1883 



Berlin 

 Physical Society, November 16. — The experiments with a 

 view to determining llie neutral point in the speetrmn in the 

 case of the colourbh'nd, which Dr. Kiinig communicated to the 

 Society in March last, have since been further prosecuted 

 by him. With the help of the apparatus, formerly de-^cribed, 

 consisting of a prism, a movable collimator, and a telescope 

 directed towards the prism's edge. Dr. Konig hud now succeeded 

 in determining in thirteen difft-rent cases of colour-blindness the 

 place of the spectuim at which these colour-blind persons felt 

 the impression of while — of the place, namely, which ap- 

 peared to them exactly of the same hue as would a surface 

 covered with magnesia and shone upon by the light of white 

 clouds. Each measurement was carried out eight times, and 

 then the average taken, by which it appeared that the error 

 in the single measurement was confined probably between 

 ± O'og and ± o'5 millionths of a millimetre. Measure- 

 ments carried out with an individual for the second time 

 after an interval of fourteen days, showed likewise the same 

 exactness. In the case of the thirteen colour-blind persons 

 who were examined, among them being both red- and green- 

 blind, the neutral point lay between ,9l'7 and 5047 millionths 

 of a millimetre, wave-length. If the persons so examined 

 were ranged in accordance with the wave-lengths of their 

 neutral point, it was found that within the limits above specified 

 they formed a fairly continuous series in which red- and green- 

 blind persons took their places indi-criminately, a result in per- 

 fect agreement with former conclusions. In his first investiga- 

 tions into the subject. Dr. Konig had further found that the 

 intensity of light exercised an influence on the situation of the 

 neutral point, and had now further prosecuted this question by 

 experiments on three individuals. For the graduation of the 

 intensity of light he made use of two Nicol prisms in front 

 of the c Uimator tube, and found, in the case of all three 

 individuals, that with increasing intensity of light the neu- 

 tral point approached closer to the violet end of the spec- 

 trum. Let the wave-length be taken as abscissa, and the 

 intensity of light as ordinate, then would the cin-ve of 

 the neutral points form no straight line, and would, under 

 great increase of intensity, mount upwards almost perpen- 

 dicularly. — Prof. Schwalbe had in the summer of this year, 

 as in former years, visited several glacial cavities, a branch 

 of inquiry in which he particularly interests himself. In these 

 investigations he took special note of the cold winds issuing from 

 fissures and clefts of the places in question. At Questenberg, 

 for example, iu the Southern Harz, he found a place where from a 

 fissure in a steep gypsum wall of about loo feet high, and having 

 a southern situation, a wind issued with a temperature of 3° C, 

 while the temperature of the air immediately surrounding it was 

 20° C. warmer. The temperature in the stone fis-ures was found 

 'ly him to be still lower, the thermometer often showing zero 

 there, while in the cavities themselves the temperature he had 

 generally observed (in July) was 5° C. Prof. Schwalbe brought 

 out the fact of the great diffu-ion of such glacial cavities. Be- 

 sides two in the Harz, he had this summer counted as many 

 as twenty to twenty-five glacial cavities, mostly quite unknown 

 hitherto, in the Karst Mountains on the southern frontiers of 

 Carniola. With regard to the explanation of this phenomenon 

 he still held by the view formeily set forth by him, that the 

 cold vas caused by the water which had been cooled to 4° C. 

 filtering through the porous stone, and he deemed a resumption 

 of Herr Jungk's experiments on the cooling of the trickling 

 water necessary to a definite decision on the cause of glacial 

 cavities. 



Physiological Society, November 23. — In the cortex of 

 the vertical lobe of the brain. Prof. Munk had, as is known, 

 demonstrated that the separate groups of voluntary muscles had 

 each of them a definite central area whence their movements 

 could be induced. One part of this cortical area was recognised 

 as the centr.al seat of the muscles of the nape and neck, and 

 after these two groups had been topically distinguished. Prof. 

 Munk conjectured that the voluntary muscles of the larynx and 

 jaws would be found to have their centre in the section of the 

 membrane appropriate to the jugular muscles. Dr. H. Kranse 

 had put this conjecture to exjjerimental proof, and found it con- 

 firmed. On bending back a dog's epiglottis and drawing for- 

 ward its tongue, the larynx could very readily be observed by 

 daylight, and when the jugular part of the cerebral membrane was 

 irritated by moderate electrical currents, he invariably noticed the 



rise if the larynx, the movement of the chorda- vocales to a place 

 situated in the middle between expiration and phonation, the 

 rise of the palate, the contraction of the constrictor pharyngis, 

 and movements of the hindermost parts of the tongue. That 

 the part of the membrane in quc-tion was the centre of the 

 laryngeal movements was further confirmed by experiments of 

 extirpation which were performed successfully on both sides 

 with ten dogs. The part of the membrane was experimented 

 on in this way first on one side and then on the other, and after 

 all inflammatory symptoms had disappeared, and the cerebral 

 wounds were cicatrised or in process of cicatrisation, it was 

 found that eight dogs had entirely lost the capability of bark- 

 ing, and, on attempting to bark, uttered either no sound or 

 only a hoarse whine, such as new-born puppies emitted. In the 

 case of the two dogs which after the operation continued capable 

 of barking, it appeared that the excision had been made too far 

 on the outside, or not deep enough. Seme dogs which after 

 the operation were no longer capable of barking were, after 

 several days, killed, when Dr. Krause searched for the nerve 

 passages, which, in consequence of the removal of the cor- 

 tical part, were degenerated. In the ganglion mamillare he 

 found a part of the nerve fibres in a collapsed, discoloured, and 

 degenerated stale, and concluded that the fibres extending from 

 the membranous centre of the larynx to its motory nerves passed 

 through this ganglion. At the invitation of the President, Prof. 

 Munk gave a brief (Ian of the topogi-aphy of the membrane of 

 the cerebrrm, on which were projected the different sensible 

 and motory nerves of the separate parts of the body. On a 

 drawing of the cerebral surface he showed the particular sites 

 which were the centres of seeing, hearing, feeling, and motion 

 for the muscles of the eyes and the ear, for the face, tongue, nape, 

 neck with larynx and throat, and for the thorax. A particular 

 locality was also pointed out for the muscles of expiration and for 

 those of inspiration. The centres for the extremities had not 

 yet been experimentally demonstrated, but no doubt they were 

 situated on the inside in the large fissure of the cerebrum, 

 where, on account of the unavoidable profuse bleeding which 

 occurred, operations were impracticable. 



CONTENTS Page 



Professor Stokes' 'Works. By Prof. P. G. Tait . . 145 

 Royal Engineer Professional Papers. I!y Allan 



Cunningham 146 



Our Book Shelf: — 



M'Cann's " Report on the Dyes and Tans of Bengal '' 147 

 Wiedersheim's " Lehrbuch der Vergleichenden Ana- 

 tomic der Wirbelthiere " 147 



Letters to the Editor :^ 



Evolution of the Celacea. — Searles 'V. 'Wood . . 147 



" Cosmic Put." — Dr. Henry Rink 14S 



On the Incubation Period of Scientific Links. — James 



Blake 148 



Meteor.— G. M. 'Whipple 148 



Physical Society, November 10. — D. J. Blaikley . 14S 

 The Ophidian Genus "Simotes." — G. A. Boulenger 149 

 The Remarkable Sunsets. By Prof. C. Piazzi 

 Smyth; Hon. F. A. R. Russell; Prof John W. 

 Judd, F.R.S. ; Dr. H. J. Johnston-Lavis ; Dr. 

 Hyde Clarke ; Howard Fox ; Sydney Hodges ; B. 

 E. Brodhurst ; Richard M. Barrington ; W. 



Hamilton; Elizabeth M. Pitman 149 



The Java Eruptions and Earthquake Waves . . . 153 

 Bicentenary of Bacteria. By Ferdinand Cohn . . 154 

 The Upper Currents of the Atmosphere .... 154 

 Electric Shadows, liy Prof. Silvanus P. Thompson 



(With Diagrams) 156 



Notes 157 



Our Astronomical Column : — 



Encke's Comet 159 



Geographical Notes 160 



The November Meeting of the National Academy 



of Sciences i r 



Ripple-Marks. By Prof. G. H. Darwin, F.R.S ..12 

 Note on Deafness in White Cats. By Dr. Lawson 



Tait 164 



University and Educational Intelligence .... 164 



Scientific Serials 165 



Societies and Academies 165 



