August 18, 1887] 



NATURE 



383 



with the co-operation of M. Kaufmann. In order to complete 

 his series of preparatory determinations on the mechanical work 

 of the muscular tissue, the author has attempted to determine 

 (he quantity of heat produced by the muscles which function 

 effectively in the physiological conditions of the normal state. 

 Hy the methods and new processes here described he claims to 

 have overcome the great difficulties inherent to studies of this 

 nature. His experiments show once more that a large amount of 

 heat is generated while the muscle operates, and of this only a 

 small quantity is absorbed by the work performed. Repeated 

 experiments will be needed accurately to determine this quantity. 

 From the experiments already made, he infers that it mostly 

 ran;;es from one-seventh to one-eighth of the total, the coefficient 

 of the latter being 0'000323 calories, and that of the heat trans- 

 formed into work generally from o 000041 to 0-000034 calories. — 

 New fluorescences with well-defined spectral rays, by M. Lecq 

 de Boisbaudran. Here the author studies alumina with the 

 earth Zo.,03 ; but as this earth has not yet been obtained in a 

 pure state, he has been compelled to employ a substance still 

 mixed with some other rare earths, notably Z^-fii ; Zo, however, 

 being greatly in excess of Zfi. Alumina containing 1/1200 of 

 ZojUj impure, heated with sulphuric acid and moderately cal- 

 cined" to a red (between the fusions of silver and copper), yields 

 a greenish-yellow fluorescence, fiint and without measurable 

 spectrum. With 1/50 of Za.^03 in the alumina, a green fluor- 

 escence is obtained, slightly yellow and dull. The spectrum 

 consists chiefly of the bands of Z)3, which apparently differ but 

 little from those obtained by reversion with a solution of 

 Z.aClo. The presence of Zo is indicated to the right of the two 

 yellow and blue bands ; but the green band of Z/3 is the 

 strongest in the spectrum, having two nebulous maximums, of 

 which that to the right is the most intense. The author also 

 announced that he had obtained some very fine fluorescences by 

 highly calcining alumina containing a little didymium or praseo- 

 dymium.— The partial lunar eclipse of August 3, observed at 

 the Observatory of Bordeaux, by M. G. Kayet. Under a three- 

 prismed spectroscope, mounted on the great equatorial (0-38 

 metre) the transition from the adumbrated to the luminous 

 part of the disk appeared very abrupt. While the spectrum 

 of the former was limited by the lines D and F, with a 

 maximum of intensity towards E, that of the partjn transi- 

 tion extended abruptly towards the red as far as Angstrom's 

 atmospheric group o. But the spectrum of the moon espe- 

 cially near the eclipsed part, was too pale to permit the use of 

 a slit narrow enough to show the at.nospheric lines. The a 

 group and the very numerous lines near D were alone distinctly 

 visible under the form of bands. — On the tides of the Tunisian 

 coast, by M. Heraud. The observations made during the 

 hydrographic survey of this coast have enabled the author to 

 study the tidal movement, the existence of which in the Gulf of 

 Gabes and on the adjacent seaboard has long been demonstrated. 

 These tides appear to be the most important and regular in the 

 whole Mediterranean basin ; but they are perceptible only on 

 the section of the coast to the south of Mehediah. They con- 

 tinually increase in magnitude as far as Gabes, where they 

 acquire a maximum of 2 metres at the mean spring-tides, thence 

 decreasing to i metre at Zarzis and on the Tripoli frontier. The 

 tidal wave appears to come from the east, the mean period being 

 apparently about 24 hours. All the observed circumstances 

 would seem to show that the relation of the lunar to the solar 

 wave is less than that of the absolute actions of the sun and 

 moon. — A comparative study of the old, eruptive and sedi- 

 mentary rocks of Corsica and the Eastern Pyrenees, by M. Ch. 

 Depcret. During a recent trip to Corsica the author had an 

 opportunity of determ'ning some very close analogies between 

 these two geological systems. Thus the central part of the 

 granitoid mass at Ajaccio is formed of a porphyroid granite dis- 

 seminated with black mica, passing thence on either side 

 insensibly to a granulitic granite, a true transitional formation 

 between the granulite type and granite. Analogous formations 

 occur in the Eastern Pyrenees, as, for instance, in the granitoid 

 mass stretching east and west between the valleys of the Aude, 

 Tet, and Boulsane. Here also the central part, extending from 

 the forest of Salvanere to Belesta, consists of a porphyroid granite 

 passing on both sides imperceptibly over to a granite with two 

 micas and granulitic texture. A comparative study of the 

 eruptive and sedimentary rocks in both regions reveals similar 

 resemblances. In Corsica the Cambrian limestone everywhere 

 worked as marble is absolutely identical with that of the 

 Pyrenees. 



Berlin. 



Physiological Society, July i. — Prof, du Bois Reymond, 

 President, in the chair. — Dr. Martius communicated the results 

 of his researches, by the graphic method, on the movements of 

 the heart. When a sound is passed into the oesophagus, and 

 connected with a Marey drum, cardiopneumatic curves are 

 obtained whose interpretation is still a matter of controversy. 

 In order to arrive at an experimental decision on this point, Dr. 

 Martius has recorded simultaneously on the same individual the 

 cardiopneumatic curves from the oesophagus and the curve of 

 impulse of the ventricular apex as obtained from the wall of the 

 thorax. It appeared from this that the curve of ventricular im- 

 pulse is of doubtful interpretation ; its shape was always the same ; 

 but it was impossible to determine with any certainty which part 

 of the curve corresponds to the svstole, and which part to the 

 diastole. Dr. Martius has therefore registered the occurrence 

 of the heart-sounds by auscultation and making signals which 

 were recorded on a rotating dram on which the curves of cardiac 

 impulse were being registered, having first ascertained that his 

 personal equation was without influence on the results. In this 

 way he was able to show that the first sound of the heart, corre- 

 sponding to the closing of the auriculo-ventricular valves, coin- 

 cides with the first rise of the curve from the base line, while 

 the second sound, or closing of the semilunar valves, coincides 

 with the second smaller rise of the curve. The Jirst rise and 

 fall of the curve corresponds therefore to the cardiac systole. 

 The speaker explained theshapeof the w//^/f curve as follows : — 

 At the commencement of the systole the auriculo-ventricular 

 valves are shut, as also are the semilunar valves since the aortic 

 blood- pressure has not yet been overcome. During this period 

 the contracting cardiac muscles alter the shape of the heart, the 

 apex moves forward, and so the curve rises. As soon as the 

 pressure in the ventricle is greater than that in the aorta, the 

 semilunar valves open and the blood begins to pour out of the 

 ventricle ; as the result of this the apex of the heart moves back, 

 and the curve falls till it reaches the base-line at the conclusion 

 of the systole and commencement of the diastole. At this instant 

 the semilunar valves close and the shock thus produced is com- 

 municated to the heart, and makes itself evident on the curve as 

 the second or valvular rise. Thus finally the first rise of the 

 curve of cardiac impulse corresponds to that period of systole 

 during which all the valves are closed ; the first apex of the 

 curve marks the instant at which the semilunar valves open ; 

 the first fall of the curve indicates that portion ofthe systole 

 during which blood is flowing out of the ventricle ; the systole 

 ends with the cojomencement of the second or smaller rise in 

 the curve. Dr. Martius has been able to strengthen this 

 analysis of the cardiac movements, so important both physio- 

 logically and pathologically, by observing that the duration of 

 the rise and fall of the curve of systole varies in different indi- 

 viduals : thus he finds, conformably with the explanation given 

 above, that in patients with low aortic blood-pre-sure, the rising 

 portion of the curve of cardiac impulse is very short, while the fall- 

 ing part is considerably lengthened, resulting from the low 

 aortic pressure allowing the semilunar valves to open sooner. On 

 the other hand, in a case of arterial sclerosis, he found the 

 rising part of the curve considerably lengthened, since the aortic 

 blood- pressure was greater, and was only overcome at a later 

 period ofthe systole.— Dr. Goldschneider presented and explained 

 plates illustrating the topography of the sense of temperature. 

 The sense of heat and cold was determined for the whole surface 

 of the body, and arranged in a series corresponding to twelve 

 degrees of intensity. As a general result, it was found that the 

 sense of cold is more extended than that of heat ; that both 

 senses are more developed on the trunk than on the extremities ; 

 that the sense of temperature is less acute in the median line of 

 the body ; that the distribution of this sense over the surface 

 of the body is quite different from that of the sense of touch ; 

 and that the points of exit of the nerves possess little or no 

 sense of temperature. 



July 15. — Prof. Munk, President, in the chair. — Dr. 

 Jacobsen gave an account of some acoustical experiments 

 which he has carried out with a view to determining the 

 law according to which the amplitude of vibration of a tuning- 

 fork diminishes as it gradually comes to rest. According 

 to theory, the diminution in the amplitu le of vibration takes 

 place in geometrical progression ; Hensen had, however, found 

 that the logarithmic decrement at first diminishes, and then, 

 when the vibrations have become extremely small, increases 



