uly 17, 1879] 



NATURE 



277 



north. The movement of the earth was plainly felt by several 

 persons in the neighbourhood. Previous to the shock the night 

 was clear, warm, and calm, mth a slight air from the south-west; 

 twenty minutes after the shock there was a thunderstorm, 

 accompanied by very heavy rain. 



From a statement in the House of Commons by the Under- 

 Secretary of State, it seems that the distribution of the Indian 

 Museum collections has not yet been determined on, and is the 

 subject of investigation by a committee in communication with 

 the authorities at the British Museum, South Kensington, and 

 Kew Gardens. The main object which is expected to be gained 

 by this step is the increased utility of the collections to the 

 public. The Economic Section, for instance, it was stated, 

 could be maintained and perfected with great public advantage 

 in the experienced hands of Sir Joseph Hooker at Kew, where 

 he already has a far better collection of similar objects ; while as 

 regards the zoological, ethnological, and art collections, their 

 transfer to departments where they will be more generally seen 

 and appreciated, seems better than to retain them in a museum 

 which, somehow or other, does not atti-act visitors. The fact 

 that 9,000/. a year will be saved to the Indian revenues, may 

 not have been without weight in deciding to break up the 

 Museum, 



The Daily Me-d/s New York correspondent telegraphs as fol- 

 lows : — " Mr. Edison has partially overcome the obstacle to his 

 electric light offered by the high price of platinum. His lamps, 

 instead of costing several dollars apiece, as at first, can now be 

 made of an alloy of platinum with inferior metals, so as to cost 

 only fifty-six cents. He announces that he can now produce the 

 spiral coil for incandescence at a price which all who use gas 

 can easily afford, and that his efforts to find platinum are only 

 induced by the desire to reduce the cost of burners still further." 



No. 27 of the Journal of the Society of Telegraph Engineers 

 contains an important paper, by Col. Bolton : " Some Historical 

 Notes on the Electric Light," consisting of abstracts from all 

 the English patents on dynamo- and magneto-electric machines 

 and on electric lights, classified and arranged in subdivisions 

 according to the special class feature of each form of machine or 

 lamp. From these abstracts it will be seen that several of the 

 so-called new inventions on this subject that have been attracting 

 so much attention of late are really inventions of long ago. 



In recent researches (described to the Vienna Academy) on 

 the specific viscosity of liquids and its relation to chemical con- 

 stitution, Herr Pribram and Herr Handl have observed (i) that 

 the substitution of CI, Br, I, and NOj for H in a molecule, 

 caused, in all cases examined, an increase in the time of flow 

 (through a capillary tube) ; (2) that this increase was least on 

 substitution of CI, and more, successively, in those of Br, I, and 

 ^ Oa ; (3) that for the absolute value of increase of the time of 

 flow, not only the quality of the element introduced, but also its 

 position in the molecule, is a determinant. 



According to Prof. Du Bois Reymond, grave sounds should 

 be more weakened by telephonic transmission than acute sounds 

 (causing an alteration of timbre), but all sounds, whatever their 

 pitch, suffer a retardation of a quarter of a wave. On the other 

 Iiaiid Prof. Helmholtz, by a theory apparently more complete, 

 finds that all sounds are weakened nearly in the same proportion, 

 and that the difference of phase introduced must be very small. 

 M. Koening has recently made experiments with a view to 

 decide the question. He substitutes two tuning-forks, A andB, 

 for the membranes of two associated telephones, and vibrates A 

 with the bow ; at once B enters into vibration, and one may, 

 either by observing successively with an optical comparing in- 

 strument, the vibrations of A and B, or by arranging A and B 

 as in the well-known experiment of M. Lissajous for composition 

 of rectangular vibratory movements, measure the difference of 



phase of the tuning-forks, which is found exactly equal to a 

 quarter of a wave-lengtli. An experiment on complex sounds 

 was made by changing one fork Utj for fork Utj so as to pro- 

 duce simultaneously the sounds i and 8 before the bar of a tele- 

 phone. The difference of phase was still found equal to a 

 quarter of a wave. Thus Du Bois Reymond's view is more in 

 accord with experiment than that of Helmholtz. 



According to Herr Kohlrausch (Ann. der -Physik, No. 6) 

 well-defined tones may be produced in a simple way by only two 

 impulses. Place two fingers of the hand loosely together, so 

 that the end of the nails are about on a level, and then tap 

 gently on the table, the proper tone of this having been 

 deadened as much as possible by means of books, or sitting on 

 it, or otherwise. It will be readily felt that the two fingers 

 seldom strike quite simultaneously, and with some attention one 

 may hear (best if the tapping be repeated twice or thrice in a 

 second) in addition to the noise, of indeterminate pitch, a very 

 bald tone of pitch varying at first with the position of the fingers, 

 but which, after a little practice, one can approximately fix. It 

 is also possible to give a musical interval by tapping twice with 

 the fingers differently adjusted ; Herr Kohlrausch says he has 

 often perceived differences of pitch to the extent of a semitone. 

 Within the interval 15 : 16, then, the tones of only two impulses 

 can be accurately determined. Tapping with only one finger- 

 nail these tones entirely disappear ; and one may therefore easily 

 learn to hear them by tapping alternately with the one and with 

 the two fingers. 



In a recent paper to the Belgian Academy M. Renard en- 

 deavours to fix the distinctive characters of calcite and dolomite 

 in rocks which contain these two elements associated in micro- 

 scopic individuals. After showing that the characters on which 

 the distinction has been established hitherto are not satisfactory, 

 he substitutes the character which dolomite has of appearing 

 nearly always with the form of the original rhombohedron, 

 whereas calcite never, one may say, affects this crystalline form. 

 It results from his observations that the dolomites which do not 

 belong to the normal type must be considered as mechanical 

 mixtures of dolomite and calcite, and not as combinations in 

 which the excess of one of the two constituent bases must be 

 interpreted according to the laws of isomorphism. M. Renard 

 supports his determinations by chemical researches under the 

 microscope, and, in concluding, he points out that in the case 

 of several dolomitic rocks of carboniferous limestone, the 

 dolomitisation is due to an action posterior to the sedimentation 

 of the calcareous elements. 



WiLLUGHBY, not WiUoughby (as printed in last week's 

 Nature) is the name of the new society for reprinting scarce 

 ornithological works, which takes its name from Francis Wil- 

 lughby, the pupil and patron of John Ray, who first edited and 

 then translated his " Ornithologice Libri tres," besides his 

 ichthyological works. 



The International African Association have just published a 

 note by Dr. Dutrieux, of the Belgian African Expedition, on the 

 subject of a parasitical cutaneous affection which he has had 

 opportunities of observing during his journey. The parasite 

 especially attacks oxen, whence it is called y^awsa ia ngSmii (ox- 

 worm). The negroes suffer a good deal from it, and it appears 

 to burrow into different parts of their feet. When it is extracted, 

 in consequence of their always going barefooted, they get very 

 painful ulcers, which Dr. Dutrieux says are exceedingly difficult 

 to cure. 



The new number of the Indian Forester contains a paper of 

 much interest on the Banda Forests, and the continuation of 

 another on the function of the pines and the larch in the production 

 of soil. There is also a letter which furnishes some curious notes 



