June 13, 1901] 



NATURE 



to the integrity of purpose and dauntless courage which 

 never failed him. Sir Spencer Walpole says justly, 



" Of all the men I have ever known, his ideas and his 

 standard were — on the whole — the highest '' (ii. 27). 



He proceeds — 



"He recognised the fact that his religious views im- 

 posed on him the duty of living the most upright of lives." 



A very unfair use has, I think, been made of this 

 opinion, which I am persuaded is based on a profound 

 misconception. However derived, it is in an innate 

 sense of moral beauty that I prefer to find the true secret 

 of Huxley's life. W. T. Thiselton-Dyer. 



TERRESTRIAL MAGNETISM AND 

 A TMOSPHERIC ELECTRICITY. 

 The Norwegian North Polar Expediiioti, 1893-96. 

 Scientific Results. Edited by Fridtjof Nansen. Vol. ii. 

 (London : Longmans, Green and Co., 1901.) 

 Report on Observations in Terrestrial Magnetism and 

 Atmospheric Electricity made at the Central Meteoro- 

 logical Observatory of Japan for the Year 1897. Pp. 

 60. (Tokio : Central Meteorological Observatory.) 



THE first of the above volumes consists of three 

 memoirs, numbered V'l., YII. and VI II., written 

 respectively by Prof. H. Geelmuyden, Mr. Aksel S. Steen 

 and Prof. O. E. Schiotz. In a brief preface Dr. Nansen 

 states that the great majority of the observations dealt 

 with were made by Captain Sigurd Scott-Hansen. 



VI. Astronomical Observations. — In a preface, pp. vii. 

 to 1.x. , Prof Geelmuyden describes the astronomical in- 

 struments and the circumstances of their use. His 

 principal object is to determine the drift of the Fram 

 and the track of Nansen and Johansen after leaving the 

 ship. The results are embodied in two large scale charts 

 (in a pocket at the end of the volume). A second object 

 is to determine the azimuth in connection with the ob- 

 servations of magnetic declination. 



The latitude and local time were found by altitude 

 observations, the sun alone being available during part 

 of the year. For the determination of longitude, and of 

 the chronometer rates, a variety of data were accumu- 

 lated. There were observations during two eclipses, a 

 few lunar distances and a number of observations of 

 eclipses of Jupiter's satellites. In connection with these 

 last data there is an enumeration of corresponding ob- 

 servations at various observatories, and a discussion of 

 the theory and of various sources of uncertainty. The 

 differences between the chronometers in use from 1893 

 to 1896 are recorded and discussed. The difficulties met 

 with in reducing the astronomical observations are con- 

 siderable. Most referred to a station in motion, while 

 many were taken at extremely low temperatures, under 

 conditions when ordinary astronomical formula; for re- 

 fraction, lie, are open to question. The differences 

 between the chronometers are not always easy to explain, 

 and the data as to their temperature corrections are some- 

 what uncertain. As to the data obtained by Nansen 

 and Johansen in their journey, in Prof Geelmuyden's 

 words, 



"the observations during this expedition, where the 

 NO. 1650, VOL. 64] 



principal work of the travellers was very often a struggle 

 for life, and where the instruments had to be handled in 

 temperatures down to -40^ C, with no other source of 

 heat than the observer's own body, could not attain any 

 high degree of accuracy" (p. Ivii.). 



The fact that the observations were made at all is the 

 strongest possible evidence that scientific zeal is com- 

 patible with the possession of remarkable physical 

 courage and resolution. 



After Geelmuyden's preface follow tables, pp. 1-136, 

 giving full details of all the astronomical observations, 

 with a few explanatory notes. 



VII. Terrestrial Magnetism. — In his introduction, pp. 

 1-9, Steen describes the instruments. Acknowledgment 

 is made of the assistance rendered by Dr. Neumayer, 

 of Hamburg, who selected the apparatus and had some 

 of it made under his own eye. The great majority of 

 the observations were taken on the ice, inside a tent or 

 a house of snow or ice. " As a defence against bears . . . 

 a weapon was always at hand, generally a revolver." 

 The position of this useful but embarrassing auxiliary 

 and its influence, or absence of influence, on the magnets 

 is a frequent item in the observational records. The 

 different magnetic elements are discussed separately. 

 The declination observations occupy pp. 10-61. The 

 majority were taken with a " Neumayer Declinatorium," 

 of which the principal feature is that its magnet consists of 

 " two laminae, between which the mirror was fixed " ; the 

 magnet rested on a pivot, but could be inverted so as 

 to determine or eliminate the colUmation error. Declina- 

 tion results are also deduced from the deflection experi- 

 ments, intended primarily for the determination of the 

 horizontal force. There were in all about 130 days on 

 which declinations were obtained. The changes observed 

 during each of these days are shown graphically, occupy- 

 ing seventeen plates. The observations seldom extended 

 over more than two or three hours on any one day, and 

 in no case was there a continuous day's record. On 

 November 24, 1894, in the course of fifteen minutes, the 

 declination changed fully 26". On no other occasion 

 did the observed range exceed a quarter of this ; but 

 changes of 2" or 3° in the course of an hour or two were 

 not uncommon. 



The discussion of the horizontal force observations 

 occupies pp. 62-126, the results being summarised on. 

 pp. 1 19-126. The apparatus was by Zschau. Obser- 

 vations of vibration and deflection were made much irk 

 the usual way. The moments of inertia of the twcK 

 magnets used had been determined, but only approxi- 

 mately, and instead of employing the values so calculated 

 use is made for each magnet of a " constant," involving 

 the moment of inertia, which was determined by obser- 

 vations made at Hamburg and Wilhelnishaven. In some 

 instances the horizontal force is deduced from a deflection 

 experiment alone, by means of a second "constant" m- 

 volving the magnetic moment of the deflecting magnet. 

 The times of vibration were taken without a telescope, 

 and no observations were made on the torsion of the silk 

 suspension. Mr. Steen also experienced some trouble 

 in connection with the temperature coefficients, which 

 had not been determined at Arctic temperatures. 



The inclination observations are discussed on pp. 

 127-165. The instrument used was a Fox circle, a& 



