April 30, 1896] 



NATURE 



611 



Dr. Gregg Wilson describes several peculiar cases of 

 reditary polydactylism, showing considerable variation in the 

 ■ isition of the abnormality, in the yoiirual of Anatomy and 

 Pliysiology. In one family, extra fingers or toes were so common 

 that they were almost expected to appear upon some of the 

 children. This abnormality persisted through six generations, 

 and two interesting features connected with it are that it 

 increased in the first four generations, and changed in position 

 from the post-axial to the pre-axial side of the limb. In another 

 case there was an increase of the abnormality, and also a change 

 in the position from the post-axial to the pre-axial side of the 

 limb. In a third case there was remarkable variability in the 

 abnormality, a man with extra minimi on both feet having one 

 son with extra great toes, and another son with extra minimi on 

 ihe hands and a double middle toe on one foot. The instances 

 studied by Dr. Wilson illustrate the variability of digital ab- 

 normalities, and in this regard they differ from the majority 

 of cases of hereditary polydactylism, where the abnormality is 

 very constant in position through several generations, though 

 not in degree. In a few cases the abnormality has been found 

 to pass in successive generations from the outer side of the hand 

 to the outer side of the foot, and vice versa, but it is rare that it 

 passes from one side of a limb to the other, as in the five 

 cases sketched by Dr. Wilson. 



On April 13 a meteorite, weighing two kilogrammes, fell at 

 Lesves, near Namur, Belgium. In its fall it very nearly killed a 

 young man who was working in an orchard, and it embedded 

 itself into the earth to a depth of 50 centimetres. The Abbe 

 Renard, who examined the specimen, considers it to be a stony 

 meteorite of chondritic structure. It consists of a whitish 

 crystalline paste, from which are detached meteoric iron, troilite, 

 olivine, bronzite, and chondroi. An examination of the struc- 

 ture and the chemical composition of this aerolite is now being 

 made in the laboratory of the University of Gand. 



The publication of Herr Gatke's theory of the moult in birds, 

 in his work on Heligoland, seems to have induced other 

 ornithologists, both in Europe and America, to turn their 

 attention to this difficult subject. Mr. Witmer Stone has put 

 forward his views " on the moulting of birds," in a communica- 

 tion made to the Academy of Natural Sciences of Philadelphia 

 in January last. He has come to the conclusion that the annual 

 moult at the close of the breeding season is a physiological 

 necessity, and is common to all birds ; whereas the spring moult 

 and striking changes of plumage effected by abrasion are not 

 physiological necessities, but depend in extent ujx)n the height 

 of development of colouration in the adult plumage, and do not 

 necessarily bear any relation to the systematic position of the 

 species. Mr. Stone scouts the idea of Gatke (adopted by Dr. 

 Bowdler Sharpe) that feathers can actually change their colour 

 without moult, unless it be by abrasion or bleaching. Mr. 

 Stone gives us a large number of useful notes on the smaller 

 land-birds of Eastern North America, based on his own 



nervations. 



A PAPER in the current number of the Annates de Chimie et 

 ae Physique gives the results of some recent determinations of 

 the specific heat of boron, made by MM. Moissan and Gautier. 

 Amorphous boron was used, and the specific heat measured by 

 means of Bunsen's ice calorimeter. The boron was heated to 

 three temperatures : 100°, 180°, and 230° C. The values for 

 the atomic heat obtained at 50°, 146°, and 213° are 3'374. 4'i53, 

 and 4766. By interpolation it is found that at a temperature of 

 about 400° C. the atomic heat of boron would be 6*4, but the 

 authors have made no attempts to make measurements at 

 temperatures over 230°. 



^ I N'CE it has been shown that the velocity of propagation of 

 electro-magnetic disturbance in a dielectric is the same as 

 NO. 1383, VOL. 53] 



that in a wire surrounded by the dielectric, the measurement 

 of the velocity of such a disturbance in a wire is of great 

 interest. M. Blondlot, who has already published the results 

 of some experiments made on this subject, contributes an in- 

 teresting paper to the current number of the Annales de Cheinie 

 et de Physique, giving the results of some recent experiments on 

 the velocity of propagation of an electro- magnetic disturbance 

 along a wire. The author employs the discharge between the 

 outer coatings of two small Leyden jars (the "impulsive dis- 

 charge " of Lodge), which occurs when a spark passes between 

 the knobs connected to the inner coatings. Each of the 

 jars has two outer coatings, one of which is connected to 

 a small spark-gap by a short wire, while the other is connected 

 to the same spark .gap by a wire about looo metres long. Hence 

 on a spark passing between the knobs connected to the inside 

 coatings, two sparks occur in the spark-gap, one produced by an 

 electro-magnetic disturbance which has only traversed a few 

 centimetres of wire, while the other, having started at the same 

 time as the first, has passed along about 1000 metres of wire. 

 An image of the sparks is thrown on to a photographic plate by 

 a mirror rotating at a known speed. The speed of the mirror 

 was determined by comparing, by means of a monochord, the 

 pitch of the note produced by the vibrations of the axle in the 

 bearings with the pitch of a tuning-fork. The " line" consisted 

 of copper wires 3 millimetres in diameter, suspended on posts 

 about 3 metres above the surface of the earth. The distance 

 between each of the outgoing wires and the corresponding 

 return, which was in the same vertical plane, was 80 cm., 

 while the two circuits were at a distance of 40 cm. from each 

 other. The mean of five sets of measurements gave 296,400 

 kilometres per second as the velocity of the disturbance, while 

 three others in which the distance traversed was nearly twice as 

 great, i.e. 1821 metres, gave 298,000 kilometres per second. 

 The author considers that each individual measurement is 

 probably correct to within i part in 100. 



The Annals of the Astronomical Observatory of Harvard 

 College, vol. xl. part iv., contain an important appendix by 

 Mr. S. P. Fergusson, upon anemometer comparisons made at 

 Mr. Rotch's Observatory at Blue Hill, Massachusetts, in the 

 years 1892-94. The object of the investigation was to determine 

 the mean differences between anemometers used as standards in 

 different countries, and to compare the results of recent whirling- 

 machine experiments. The observatory in question is admir- 

 ably adapted for the purpose, being situated upon an isolated 

 hill, and is equipped with the best patterns of anemometers, in 

 addition to which some instruments were supplied from other 

 places for comparison. The anemometers, and method of com- 

 parison are fully described ; very useful results were obtained, to 

 which, however, we can only briefly allude here. The experi- 

 ments show conclusively that the smaller anemometers are the 

 most sensitive to sudden variations in velocity, the ratio of sen- 

 sitiveness being nearly proportional to the size, in instruments of 

 the same type. The fan anemometers are much more sensitive 

 than the cup anemometers, and are therefore the most efficient 

 for recording gusty winds ; the Robinson pattern instruments, 

 mostly used in this country, are least efficient in this sense, but 

 they possess undoubted advantages for recording mean velocities»^ 

 Dines' pressure tube anemometer was found to be an excellent 

 instrument, especially for indicating maximum velocities. The 

 comparisons clearly show the need of some standard form of 

 anemometer, to which all observations heretofore made can 

 be reduced. 



The results of much patient observation are recorded in 

 Bulletins 129 and 130 of the Michigan Agricultural Experiment 

 Station, which relate to fruit culture. Numerous varieties of 

 fruits, embracing 156 of strawberries, 53 of raspberries, 30 of 



