Jan. 23, 1879] 



NATURE 



275 



observation and principles which have worked like a 

 master-key in opening to our understanding the meaning 

 of this wonderful region. Without those methods and 

 principles it would have been of comparatively little utility 

 to attempt to solve the problems of such a region. Those 

 whose privilege it has been to carry them into practice 

 will ever be glad to acknowledge how great is their 

 indebtedness. 



INCLINA TION OF THE AXES OF CYCLONES 

 AND ANTICYCLONES 



I HAVE during the last seven years endeavoured, 

 though apparently without much effect, to direct the 

 attention of meteorologists to a law which I conceive to 

 be of very high importance in relation to the theory- of 

 the movements of the atmosphere. The law to which I 

 refer is this : — The movements of the upper-currents 

 prove that the axis of a progressive cyclonic circulation 

 is commonly inclined, so that the extremity nearest to the 

 earth's surface is considerably in advance of that in the 

 higher regions of the atmosphere. A barometric minimum 

 consequently occurs at any locality on the earth's surface 

 some hours before the corresponding minimum in the 

 higher regions passes over the same spot (" Laws of the 

 Winds Prevailing in Western Europe," pp. 156 to 162, 

 1872 ; Meteorological Magazine, vol. x. pp. 92 to 93, 

 1875 ; Quarterly Journal of the Meteorological Society, 

 October, 1877, pp. 440 to 445). I have also pointed out 

 that the axis of an anticyclonic circulation has, at least in 

 some instances, a similar inclination ; a point which will 

 be discussed more fully in a future paper. 



I hope that the results, strongly confirmatory of this 

 law, which Prof. Loomis has recently derived from his 

 examination of the wind and barometer reports from 

 Mount Washington, Mount Mitchell, and Pike's Peak, 

 will attract more attention than my own deductions from 

 upper-current observations have done. In his tenth paper 

 of "Contributions to Meteorology" (^American Journal 

 of Science and Arts, January-, 1879), Prof. Loomis shows 

 that with very few exceptions the barometric minima 

 occur at the base of a mountain considerably earher than 

 at the simimit, the retardation amounting to about one 

 hour for an elevation of from 900 to 1,300 feet, and that 

 the maxima appear to follow the same law. 



Other points of agreement between the results of cloud 

 observations in Europe, and those obtained from the 

 reports of the mountain observatories in America, seem 

 to me to be of great interest. I would especially call 

 attention to the substantial coincidence of these results as 

 regards, first, the rarity of easterly upper-currents, as 

 compared with easterly surface-winds ; and secondly, the 

 higher, and also less variable, value of the angle made by 

 the northerly, than that made by the westerly upper- 

 currents, with the direction of the centre of lowest 

 pressure at tae earth's surface. W. Clemext Ley 



BARTOLOMEO GASTALDI 

 C IN'CE the last anniversary' of the Geological Society 

 •-^ many distinguished men among its members, both 

 m this and foreign countries, have been removed by 

 death. We regret to have to add to the sad list the 

 name of Prof. Gastaldi, the well-known head of the Italian 

 Geological Survey. 



Bartolomeo Gastaldi was born at Turin, in the year 

 1818, and was originally destined by his father for a legal 

 career; his fondness for geological studies, however 

 proved too strong to be repressed, and he was eventually 

 entered as a student at the Ecole des Mines at Paris 

 Here, and throughout his subsequent career, he enjoyed 

 the friendship of Quintino Sella, who afterwards became 

 so distinguished ahke in Italian scientific and political 

 circles. ^ 



Gastaldi had reached the age of twenty-eight before his 

 first scientific memoir was published, and his earliest 

 essays in this direction were devoted to anatomical and 

 palaeontological questions. Before long, however, he 

 seems to have discovered that the true bent of his genius 

 was towards physical geology. In his studies in this 

 department of science he was greatly aided by his powers 

 as a pedestrian, and he soon made himself familiar with 

 all the southern spurs of the Alpine chain. In company 

 with his friend Sella he founded the Italian Alpine Club, 

 of which he was the second president. 



He succeeded Sella as Professor of Geology at the 

 Engineering School of Turin, and subsequently became 

 Professor also at the University. During the later years 

 of his life the work of the Geological Survey, of which 

 he was made director by the Italian Government, occu- 

 pied much of his attention, and to his energy and capacity 

 much of the success which has already attended that 

 important work is due. 



^o less than thirty papers on various branches of 

 geological science have proceeded from Gastaldi's pen. 

 He was an advocate, during his later years, of extreme 

 views upon glacial subjects, and many of the views which 

 he propounded on this and on other questions of Alpine 

 geology have not been generally accepted by the geolo- 

 gists of other countries. In some of his speculations, 

 indeed, his boldness seems to have outrun his caution. 

 Those who had the happiness of a personal acquaint- 

 anceship with Gastaldi describe him as a most sanguine 

 and earnest student and a warm-hearted friend. 



Prof. Gastaldi was a Corresponding Member of the 

 Geological Society of London, and received similar 

 honours from the academies of many other foreign 

 countries. In Turin, where he spent the greater part of 

 his life, and where he occupied the position of a Common 

 Councillor, he was very greatly respected and beloved ; 

 this fact is testified to by the circumstance that at his 

 funeral more than three thousand people followed his 

 remains to the cemetery. 



ON THE DETERMINATION OF ABSOLUTE 

 PITCH BY THE COMMON HARMONIUM-^ 



THE methods described depend upon the principle 

 that the absolute frequencies of vibration of two 

 musical notes can be deduced from the interval between 

 them, i.e., the ratio of their frequencies, and the number 

 of beats which they occasion in a given time whea 

 sounded together. For example, if x and y denote the 

 frequencies of two notes whose interval is an equal temr 

 perament major third, we know that y = i '25992 x. At 

 the same time the number of beats heard in a second, 

 depending upon the deviation of the third from true 

 intonation, is 4_y — 5 x. In the case of the harmonium 

 these beats are readily counted with the aid of a reso- 

 nator tuned to the common over-tone, and thus are 

 obtained two equations from which the absolute values 

 of :r and_y may be found by the simplest arithmetic. 



Of course, in practice, the truth of an equal tempera- 

 ment third could not be taken for granted, but the diffi- 

 culty thence arising would be easily met by including in 

 the counting all the three major thirds which together 

 make up an octave. Suppose, for example, that the fre- 

 quencies of c, e, g^ c' are respectively x,y, z, ix, and 

 that the beats per second between x and_>' are a, between 

 y and z are b, and between z and 2 x are c. Then, 

 \y-lx=a, 

 4z - Sy = b, 

 Zx- 5z = c, 

 from which 



^ = i (2Sa + 2ob+i6c), 

 y = i{32a + 2Sb-{-20c), 

 z =J(4oa-|-32^-|-2S<r). 



» Abstract of a paper read before tte Mu'-ical A^^tc'atijn, December » 

 1l^% by Lord Rayle gh, F.K.S. 



