April $o, 1885] 



NA TURE 



019 



ascertained by means of the 1 tcim iter the duration of sunshine at 

 a given place, its intensity with relation to the height of the sun 

 and the clearness of the air ; and then by means of the sunshine- 

 recorder the period- during which the sun shone more or less were 

 ' students of vegetable physiology 



' to make use of both instruments. — On the 



renal capsules-. Prof. G. Tizzioni 

 has continu on animals from which he had 



renal capsules. The result of the last ex- 

 ternals which survived the opera- 

 red no change in health, in nutrition, or development. 

 In those cases in which an abnormal bronze coloration was seen 

 in the lips and the mucous secretions of the mouth and nose, it 

 was ascertained that this coloration stopped short at a certain 

 point, and only in exceptional cases began to increase again so 

 tions ; but there was observable a di- 

 minution, or even entire disappearance, of these pigmen 

 1 I the rabbits experimented on was there any impoverish- 



ment of the 1 : the proportion of haemoglobin 



mal. The important fact in this com- 

 municati. 1 in this, that the supra- 



newed, and that when that takes place 

 the new capsule arises at a position situated a; some distance 

 from that occupied by the old capsule which had been 

 removed. The tissue giving rise to the new organ is that of 

 the sympathetic nervous system, and hence the capsules belong to 

 life: We hive thus the demon- 

 stration n t only of the po sibility of the reproduction of an 

 entire organ, but also of the nature of that process ; and the 



lions as to the functions of tl 

 are now fixed. — I I l a 1 



Sig meeting the result of his crystal- 



of the Golu ill lite which he 

 some specimens of pegmatite forming an extensive deposit near 

 since of Ossola). In these 

 1 I ia had already discovei 



The columbite investigated 

 is a new mineral, not only for Italy, but even for the whole chain 

 of the Alps. The degree of hardness of its crystals was found 

 - the presence of iron and man- 

 vas revealed. — On sylvic acid. Dr. L. Valente has 

 succeeded in obtaining from colophony (common rosin) a well- 

 determined acid, called sylvic acid. This is the only well 

 characterised acid that has been extracted from colophony since 

 i by Lieberman, an! the reactions ob- 

 tained by him by means of a supposed sylvic acid show by the 

 he was only operating with a mixture. 

 researches, the incomplete 

 which he presented on this occasion on the ground of 

 v. Other communications : — Drs. Ricini and Marino - 

 Zuco reported on the reactions obtained by them by means of 

 -Dr. Mendini reported on the results 

 obtained in studying the action of bromine on pyrotartaric and 

 citicemic imide. 



Berlin 



Physiological Society, March 13. — Dr. Goldscbeider gave 

 a short -ketch of his investigations respecting points of sensation 

 of warmth, coldr,. re, in connection with the sense of 



feeling. The doctrine of the specific energies of the nerves, accord- 

 IDg to which each nerve-fibre was able to conduct only a definite 

 quality of stimulations and sensations, had to encounter. a = was 

 known, great difficulties in connection with the sense of smell and 

 the sense of touch, seeing that the number of smells was very 

 manifold, and that, consequently, very many essentially different 

 sensations were taken up and conducted by the primitive fibres 

 of the nerves of smell, while, again, the stimuli acting on the 

 nerves were also qualitatively diverse. Jn the case of 

 the sense of smell the difficulties would perhaps only be resolved 

 when the very various smells were satisfactorily reduced to a few 

 simple fundamental sensations. With respect to the sense of 

 feeling, on the other hand, a sense which comprised the five 

 different qualities of pain, pressure, tickling, warmth, and cold, 

 the latest researches went to show that here in point of fact were 

 d fferenl nerve-terminal apparatuses to be distinguished, each 

 w ith its own specific energy. In examining the sense 

 dure in the skin by means of rounded metallic points, 

 the speaker found that there were a very large number of 

 points which were sensitive to cold, and also a number of other 



points which were sensitive to warmth. These were unequally 

 distributed over the body, and decreased in number and density 

 toward- the periphery. They appeared to stand in a certain 

 contrast to the fineness of the sense of touch, being found more 

 rarely where the sense of touch was very delicate." On a more 

 minute study of these points it was shown that they were ranged 

 together in the form of chains, and that there w 

 chains of cold or of warm points, as the case might be, radiating 

 >ot of the skin. These radiating centres lay, in the 

 . to the number of about So per cent., each at 

 hair, though all hairs did not cover radiatin ; 

 of such chains, while, on the other hand, there were radiating 

 situated at the roets-of hairs-. The chains of col 1 points. 

 again, never coincided with th ise of warm points ; but these 

 two sets of chains lay adjacent to each other. The cold points 

 were alone capable of generating cold impressions, while all 

 other points of the skin never excited such cold sensations. 

 There were, however, differences am ng the cold poin 

 much as some always gave rise to the exclusive feeling of cool- 

 others, even under weak stimulations, always pro- 

 duced only an intense feeling of cold. Entirely analogous to 

 this arrangement was the arrangement of the warm poin 

 generated the single feeling of lukewarmness, others that of 

 warmth, and others, again, that of severe heat, no matter 

 what the degrees of stimulation in the three different cases. Not 

 only oscillations of temperature, but also mechanical and electri- 

 cal stimulations, produced the feeling of cold at the cold points, 

 and at the warm points the feeling of warmth. On the other 

 hand, neither at the cold nor at the warm points did the prick of 

 a fine needle cause a painful sensation. The cold and the warm 

 point- were anatomically sharply defined, and were constantly 

 found respectively at the same spots of the skin. On further 

 investigation it was, however, ascertained, after taking observa- 

 il times of small sections of the skin, that, in conse- 

 quence of fatigue and habituation due to repeated stimulations, 

 the points very soon ceased to act ; but, on being left for a con- 

 siderable time in repose, they came decisively into operation 

 again at the same spots. The localisation of the sense of tem- 

 perature was a highly developed one. When 

 least distance at which two cold impressions were felt distinctly 

 from each other, it was found at spot which contained few cold 

 points to attain a maximum of from 4 to 6 mm., while the mini- 

 mum was o'S mm. Dr Goldscheider had made minute topo- 

 gnphical studies on his own body in respect of the distribution 

 of the points of temperature, and in general he had established 

 that the number of warm points was less than that of cold points, 

 that there were parts of the skin where neither cold nor warm 

 points occurred, and that other parts contained indeed a few 

 cold but no warm points — the glabella, for example. On the 

 other hand, there was no spot on the surface of the body where 

 warm points were found without the presence of cold points. In 

 the outspreading areas of the sensory nerv s, especially in those 

 of the facialis, warm and cold points were numerous ; but they 

 were sparingly found in the middle lines of the body, as also 

 over the bones. In regard to the theory of the sensations of 

 temperature, Dr. Goldscheider ranged himself on the side ' 

 We cr view, and assumed that a rise of temperature in the 

 skin generated the feeling of warmth — that is, excited the 

 warm points, while a depression of temperature created the 

 feeling of cold, by stimulating the cold points. The experi- 

 ments on the contrasting effects of temperature were very 

 easily explained by this theory, when it was considered that 

 each stimulation of the cold or warm points blunted them a 

 little, and so rendered them more insensible to the next stimula- 

 tion. Dr. Goldscheider, after the greater part of his experiments 

 were concluded, received information that, previously to him, 

 Herr Blix had demonstrated the existence of cold and warm 

 points, and their electrical excitability ; and, so far as these 

 lendent series of observations covered each other, they 

 completely coincided with each other in their results. After the 

 speaker had thus conclusively established the specific energy of 

 the sense of feeling in respect of the sense of temperature, he 

 applied himself to examine the sense of pressure by means of 

 fine cork points attached to a spiral spring. lie found the sense 

 of pressure likewise distributed over the skin in the form of 

 print- ; and the points of pressure, which coincided neither with 

 the cold nor with the warm points, but occupied altogether spe- 

 cial spots of the skin — the sites of special nerve-apparatuses — 

 were also arranged in chain-like rows, these rows likewise radi- 

 ating from particular points. On the whole, the results in respect 



