August 3, 1882] 



NA TURE 



335 



used to the absolute exclusion of the other. The epoch, 

 however, to which the present speculations relate is that in which 

 he had not reached the present symmetric development of his 

 intellect and of his bodily organs, and the inquiry i-, Which 

 mode of communication was earliest adapted to his simple wants 

 and informed intelligence? With the voice he could imitate 

 distinctively but few sounds of nature, while with gesture he 

 could exhibit actions, motions, positions, forms, dimensions, 

 directions, and distances, with their derivations and analogues. 

 It would seem from this unequal division of capacity that oral 

 speech remained rudimentary long after gesture bad become an 

 efficient mode of communication. With due allowance for all 

 purely imitative sounds, and for the spontaneous action of vocal 

 organs under excitement, it appears that the connection between 

 ideas and words is only to be explained by a compact between 

 speaker and hearer which supposes the existence of a prior mode 

 of communication. This was probably by gesture. At least 

 we may accept it as a clue leading out of the labyrinth of philo- 

 logical confusion, and regulating the immemorial quest of man's 

 primitive speech. 



SCIENTIFIC SERIALS 

 Verhandlungm des naturhisloriscRcn Verdnes tier Pretts- 

 sischen Rkdniamle und Wat/alms, 1881. Zweite Halfte.— We 

 note here the following : — On some Anthozoa of the Devonian, 

 by I'rof. Schluter. — The Stromatopora of the Khenish Devonian, 

 by Herr Bargatsky. — Geological sketch of a journey through 

 Palestine and the Lebanon region, by Prof, von Rath. — On the 

 building art of birds, reduced to its true value, by Prof Landois. 

 — The beetle genus Briic/ms, Linn., and especially Bruchus 

 pisorum, Linn., by Herr Cornelius.— On new finds of saurian 

 tracks in the Wealden Sandstone of the Buckeberg, by Herr 

 Grabbe. — The Royal Mercury Works at Idria, by Heir Fa- 

 bricius.— The zinc ore deposits of Wiesloch, by Herr von 

 Decken. — Bone-remains from the Schipka Cave in Moravia, by 

 Prof. Schaaffhausen. — Removal of an iron fragment from the 

 eyeball with an electromagnet, by Dr. Samuelsohn. — Skulls 

 from Kirchheim, by Prof. Schaaffhausen. — Influence of the use 

 of transportable pneumatic apparatus on the circulation of ra 

 healthy man, by Prof. Finkler. — On a colossal femur of the 

 horse, found in January, 1880, when removing ].art of a bank of 

 the Wupper at Elberfeld, by Prof. Schaaffhausen. — On so- 

 called cosmic dust from Dresden, by Prof, von Lasaulx. — New 

 apparatus for continuous application of weak galvanic currents, 

 by Prof. Finkelnberg. — On the earthquake of Ischia, March 4, 

 t88i, by Prof, von Rath. — On eruptive gneiss in Saxony and 

 Bavaria, by Dr. Lehmann. — Nerve-stretching ; three cases, by 

 Prof. Doutrelepont. 



SOCIETIES AND ACADEMIES 

 London 

 Aeronautical Society, July 17. — A paper, upon the action 

 of the pectoral muscle in the flight of a bird, was read by Mr. 

 Fred. W. Brearey. He said that it behoved all experimenters 

 in flight to reduce their theories into a demonstrable form. It 

 had often been stated for instance that the power exerted by a 

 bird in its flight had been greatly exaggerated, but no one had 

 hitherto proved his assertion. It was capable however of satis- 

 factory proof by demonstrating artificially the action of the pec- 

 toral muscle, by the aid of which weight became an accessory to 

 power. When the bird committed itself to the air the upward 

 pressure in the wings stretched the elastic ligament, which formed 

 part of the muscle, to such an extent as to allow of the bird 

 gliding upon the air without any exertion. The weight of the 

 bird was the measure of this elasticity. It was said by some 

 that at least the bird must possess the power by the downward 

 stroke of the wing to raise its own weight. But Mr. Brearey 

 said that this was not an absolute necessity, because the reaction 

 of this elastic ligament aided the force of the down stroke. He 

 proceeded to verify his assertion by the action of a model, with 

 wings of four feet spread, under whichbehad attached an elastic 

 cord passing under the body of the model. Upon committal to 

 the air this just allowed of the wings being expanded, so that the 

 model would glide downwards. He then detached the cord and 

 wound up his power, calling attention to the fact that he had 

 wound the india-rubber strands thirty-two times. He showed 

 however that although this was sufficient to create a vigorous 

 flapping of the wing when held in the hand, yet when committed 

 to the air it had not the power to give one downward stroke, and 



therefore it could only glide as before. Holding it again with 

 the cord attached and the power wound up the same number of 

 times, he showed that it was unable to flap the wing, because 

 the two forces were exactly held in equilibrium. There was a 

 third factor wanted before it could fly — and that was weight. 

 The model being liberated, flight was well sustained, and upon 

 being set free several times without being wound up any further, 

 it appeared able to fly with a very weak power. The same thing 

 was observable with another model, composed entirely of a loose 

 surface thrown into a wave action — his own invention. Mr. 

 Brearey remarked that this economy in flight can only be obtained 

 by something of the nature of wing action, and must be wholly 

 wanting in any apparatus actuated by the screw. 



Edinburgh 

 Royal Society, July 17. — Prof. Balfour, vice-president, in 

 the chair. — Prof. Heddle read a paper on the sequence of 

 rocks in the North-West Highlands, a point on which there had 

 been and still was a great deal of controversy. The author had 

 examined eighteen sections in the region around and to the north 

 of Loch Maree, and had convinced himself that Murchison and 

 Geikie were in the main correct. The succession of the rocks 

 was found to be as follows : — Torridon Conglomerates, Lower 

 Quartzite, Dolomite Series, "Logan" Rock, Upper Quartzite, 

 Upper Gneiss. The dolomite does not extend so far west as the 

 quartzite and Logan Rock, and is of no great lateral extent, but 

 it stretches as a thin strip of shallow water deposit from end to 

 »nd of the whole district. — Prof. Tait communicated a paper by 

 Mr. Wm. Peddie on the rotation of plane of polarisation by 

 quartz and its relation to wave-length. The spectrum of a ray 

 of light which has been transmitted through the polariser, a 

 piece of quartz, and the analyser, exhibits one or more absorp- 

 tion bands (the number depending upon the thickness of the 

 quartz), which move along the spectrum as the analyser is rotated. 

 By direct comparison of this spectrum with the ordinary solar 

 spectrum in juxtaposition, the rotation for any Fraunhofer line 

 can be estimated with considerable accuracy. The rotations 

 were expressed in terms of the inverse even powers of the wave- 

 lengths as far as the sixth. — Mr. W. W. J. Nicol, in a paper on 

 the condition of ammonium salts when dissolved in water, 

 explained the abnormal expansion of solutions of ammonium 

 chloride and other ammonium salts by the partial dissocia- 

 tion on solution in water — an explanation suggested by the 

 well-known fact that such salts become acid on boiling. This 

 view of the matter seemed further to explain other anoma- 

 lies in the behaviour of ammonium chloride solution — such for 

 example as its surface tension investigated by Quincke, and its 

 coefficient of absorption for carbon dioxide as determined by 

 Mackenzie. — Mr. J. Y. Buchanan described a new form of solar 

 calorimeter which he had used in Upper Egypt at the time of 

 the last eclipse. The sun's rays were concentrated by suitable 

 reflectors upon a glass tube, two inches long, which formed the 

 upper end of a Liebig's condenser, and was mounted equatorially 

 so as to follow the sun's motion. The heat was measured by the 

 amount of water distilled in a given time. The results obtained 

 were very satisfactory, agreeing with the resulis given by other 

 methods. — Prof. Crum Brown read a continuation of the paper 

 by Messrs. Laurie and Burton, on the heats of combination of 

 the metals with the halogens, estimated from electromotive force 

 observations. Their result for the heat of combination of zinc 

 with iodine in the presence of water differed by barely 2 per cent, 

 from Andrews' value. Other results did not agree so well ; but 

 this was hardly surprising where so many factors entered into 

 the experiments. The most accurate method was no doubt to 

 let a chlorine, iodine, or bromine cell with given poles run 

 down in a calorimeter and estimate the heat so given out. 

 — Professor Brown also communicated a long paper by Mr. 

 W. L. Goodwin, on the nature of solution, in which the 

 author made a careful investigation into the solution of chlorine 

 in various liquids at different temperatures. Experiment showed 

 that there was in many cases a temperature of maximum solu- 

 bility, a fact which Mr. Goodwin explained as due to the forma- 

 tion at lower temperatures of a chlorine hydrate whose rate of 

 increase of solubility with increase of temperature quite masked 

 the simultaneous decrease of solubility of the gas until a tempera- 

 ture was approached at which the chlorine hydrate could no 

 longer exist. — The second part of the description of new and 

 little-known phanerogamous plants from Socotra, by Prof. 

 Bayley Balfour, was received as read. — The chairman, in 

 bringing to a close the hundredth session of the Society, gave 

 a brief review of the session's work. 



