June ii, 1903] 



NA TURE 



133 



and used successfully a slipping plate for use in the 

 principal focus for photographic and visual purposes. 



Not only was his time chiefly devoted to the construc- 

 tion of these astronomical instruments, but he turned 

 them to great advantage by showing what could be 

 done with them. Among the most noteworthy of these 

 attainments was the magnificent photograph of the 

 nebula of Orion which he secured in 1883, and for 

 which he won the gold medal of the Royal Astro- 

 nomical Society. Nebulge, star clusters, &c., all came 

 under his keen eye, and his researches not only demon- 

 strated the cumulative effect of the photographic film, 

 but showed that a new field of astronomical work was 

 dawning by the employment of reflectors for long 

 exposure photography. 



More recently Dr. Common, among other things, 

 turned his attention to the improvements in telescopic 

 gun sights, and in this direction his loss will be keenly 

 felt. He became a fellow of the Royal Astronomical 

 Society in 1876, received the gold medal in 1884, and 

 was president in 1895-96. He was elected a fellow 

 of the Royal Society in 1885, and was an honorary 

 LL.D. of St. Andrews. 



Jovial, good-hearted, good-natured, and generous 

 beyond degree in distributing his mirrors to those who 

 would use them, all his friends join with the widow, 

 son and three daughters whom he has left behind in 

 mourning the loss of a personal friend. 



William J. S. Lockyer. 



PROF. C. A. BJERKNES. 



T N Nature of May 28 mention was made of the 

 A death of Prof. C. A. Bjerknes, of the University 

 of Christiania, at the age of seventy-eight. 



Though occupying the chair of pure mathematics, 

 it was to applied mathematics, and especially to hydro- 

 dynamics, that Bjerknes devoted the greater part of 

 his attention and study. He studied mathematics at 

 the University of Gotti'ngen early in the •' fifties," his 

 teachers including Riemann, who lectured on Abelian 

 functions to a class of three only — Schering, Bjerknes 

 and Dedekind — presumably between 185 1, when 

 Riemann obtained the doctorate, and 1859, when he 

 was appointed ordinary professor, also Lejeune Dirich- 

 let, who lectured to Schering and Bjerknes in 1855-56, 

 and who proposed to them the problem of the ellipsoid 

 in a steady fluid current. Solutions were given by both 

 Schering and Bjerknes, but it was not until 1873 that 

 Bjerknes completed his work on the problem of the 

 general motion of an ellipsoid in fluid. 



Bjerknes was at an early date attracted by the prob- 

 lem of replacing action at a distance by action of an 

 intervening medium, and he exhibited considerable 

 originality in the energy with which he took up the 

 advancement of a doctrine which at that time received 

 little support. The discovery that a sphere could 

 move through a perfect liquid without retardation 

 having shown that the existence of an ether does not 

 involve a violation of Newton's first law, Bjerknes 

 set to work to investigate the forces acting between 

 two spheres moving in liquid, and in particular he 

 developed the notion of " pulsating " spheres, i.e. 

 spheres fluctuating periodically in volume, finding that 

 between such spheres attractions and repulsions exist, 

 obeying the law of the inverse square, and their sense 

 being dependent on whether the phases are the same 

 or opposite. The discussion of all the terms entering 

 into the expressions for the forces was not completed 

 until a comparatively late date, and in the meanwhile 

 dynamical theories of physical phenomena have de- 

 veloped in other quarters, and ethers differing in their 

 properties from ordinary matter, and in particular 



NO. 1754, VOL. 68] 



from matter in a fluid state, have come into existence. 

 But another interest was aroused in these hydro- 

 dynamical attractions and repulsions by the experi- 

 mental verifications of the results of the theory which 

 were successfully carried out by both Prof. C. A. 

 Bjerknes and his son, and of which we hope to give a 

 fuller account shortly. These experim.ents were com- 

 menced in 1875, using rough and ready methods, but 

 the apparatus have been gradually improved, and a 

 number of papers on the subject were published, chiefly 

 in the period 1878-1880, by Bjerknes and Schiotz in the 

 Christiania Forhandlinger. 



Among Bjerknes 's other writings we note the bio- 

 graphical notice "Niels Henrik Abel; tableau de sa 

 vie et de son action scientifique," published at Paris 

 in 1885. Prof. V. Bjerknes has for many years col- 

 laborated with his father, and the second volume of 

 his " Vorlesungen nach C. A. Bjerknes' Theorie " 

 only appeared quite recently. G. H. Bryan. 



NOTES. 

 Mr. Balfour has accepted the presidency of the British 

 Association for the meeting to be held at Cambridge in 

 1904. 



Prof. Ray Lankester has been elected a Foreign 

 .\ssociate of the National Academy of Sciences, Washing- 

 ton, and a member of the American Philosophical Society, 

 Philadelphia. 



We learn from the Paris correspondent of the Times that 

 a monument, which has been erected by public subscription 

 to the memory of Pasteur, was unveiled at Chartres on 

 Sunday. This memorial specially commemorates the 

 services of the great bacteriologist to agriculture by his 

 discovery of a specific for anthrax, which resulted from a 

 long series of experiments undertaken at a local farm. 

 The principal feature of the monument is a high relief, 

 which represents Pasteur and his assistants at work. It is 

 the design of Dr. Paul Richer, who, besides being a 

 member of the Academy of Medicine, is a distinguished 

 sculptor. 



A Reuter message from Simonstown, dated June 9, 

 states that the German Antarctic ship Gauss arrived there 

 on Tuesday morning after a successful year's work in the 

 South Polar regions. She will remain there for three 

 weeks to refit, and will then sail for home. On sailing 

 from Cape Town the Gauss called at Kerguelen Island, and 

 landed a party, which reached the floating ice on 

 February 14, 1902. The ship was ice-bound on February 

 22 in lat. 665, long. 90. New land was discovered, which 

 was named the Emperor William II. Land. This was 

 covered with ice, with the exception of an inactive volcano. 

 The expedition was ice-bound here for almost a year, and 

 many scientific investigations were carried out during this 

 period. The ship left the ice on April 8 and proceeded to 

 Durban, passing Kerguelen Island, and calling at St. Paul 

 and New .\msterdam Islands. The members of the ex- 

 pedition enjoyed good health, there being no case of sick- 

 ness, accident, or death during the whole cruise. Prof. 

 Drygalski speaks in the highest terms of the vessel's be- 

 haviour, both in the sea and in the ice. 



The Hanbury gold medal has this year been awarded to 

 M. Eugene Collin, 6cole de Pharmacie, Paris. 



A TABLET placed on the wall of Coate House, near 

 Swindon, Wilts, the birthplace of Richard Jefferies, was 

 unveiled by Prof. N. Story Maskelyne on June 6. 



