6i4 



NATURE 



[April 26, 1900 



corresponds to its one degree of freedom on Boltzmann's 

 theory of partition of energy, I am afraid the amount of 

 energy of this kind on each particle is hardly sufficient to 

 account for any observable phenomenon. That it may, 

 however, be much greater seems justified by the failure 

 of this theory, so far as is known, in other cases, and this 

 must be my excuse for calling attention to what seems 

 certainly a vera causa for structures and actions in 

 matter of a size comparable with the heat vibrations in 

 the ether, even though the amount of this cause may, 

 when fully investigated, turn out to be so small as to be 

 insufficient to produce observable effects. 



Geo. Fras. FitzGerald. 



REPORT OF THE MALARIA EXPEDITION 

 TO SIERRA LEONE. 



FOLLOWING close on the "Instructions for the 

 Prevention of Malaria," the Liverpool School of 

 Tropical Medicine have issued the report of the malaria 

 expedition sent out to Sierra Leone by that body in 

 August last. Their objects, as stated in the report, 

 were : — 



(i) To find one or more species of insects hospitable 

 to the human Hfemamoebida; on the West Coast of 

 Africa. 



(2) To study the bionomics of these insects, with a view 

 to suggesting better modes of prevention of malarial 

 fever than those hitherto known to us. 



The tercninology adopted is that used by Major Ross 

 in consultation with Prof. Herdman, already noticed in 

 Nature (August 3, 1899). It is proposed to abolish 

 the word mosquito, and use the old English equivalent, 

 gnat, as there is no difference between the two, and be- 

 cause the terms malaria and malarial fever no longer 

 hold — they propose the term htemamoebiasis, or gnat 

 fever. 



The genus Anopheles was chiefly looked for, because 

 these had been shown to be concerned in the trans- 

 ference of the parasite. In the barracks at Wilberforce, 

 Sierra Leone, 25 per cent, of the soldiers suffered from 

 all three forms of malaria or gnat fever. All the gnats 

 caught in the barracks were Anopheles costalis except 

 one, and out of 109 of those examined, parasites were 

 found in 27. 



Some experiments on feeding Anopheles on a patient 

 with H. malariae gave positive results, several young 

 zygotes being found in the gnat. These gnats were 

 caught in a building where there were no fever patients, 

 and numbers of them had been examined and found free 

 from parasites. When, however. Anopheles bred from the 

 larvae and kept in test tubes were applied to the skin 

 of a patient, they were found not to feed copiously, and 

 negative results, as regards zygotes, were obtained on 

 dissecting them. It is suggested that the explanation 

 •of the failure was the non-fertilisation of the females ; it 

 seems that the female gnat requires blood for the nutri- 

 tion of the eggs. If the ova are not fertilised, the blood 

 is possibly evacuated without some digestive process 

 being performed which may be necessary to the vitality 

 of the zygotes. 



Measures of precaution against the bites of gnats, and 

 measures for reducing their numbers, are discussed in 

 the chapter on prevention. It is remarked that neither 

 Europeans nor natives made any effort to keep down 

 the numbers of gnats, which constitute a very serious 

 pest in Sierra Leone, as they do in all tropical towns. 

 Both this report and the " Instructions for the Preven- 

 tion of Malaria" should be invaluable to residents abroad, 

 as indicating how they may protect themselves from the 

 annoyance from gnats, and from the evil results that may 

 arise from their "bites." 



Experiments were instituted with a view to destroying 



NO. 1 59 1. VOL. 61] 



the adults or larva;, and to prevent the insects from 

 breeding. It was not always possible to discover the 

 breeding pools of the Anopheles infecting a particular 

 spot ; for instance, none could be found at Wilberforce, 

 the nearest pools where larvae were found being nearly 

 a mile away. Dr. Fielding Ould tried experiments with 

 tar, and found the film on the surface of the pool lasted 

 longer than a film of kerosene oil ; while both killed the 

 larvas and prevented them from hatching so long as the 

 film lasted. 



In the addenda are some good micro-photographs of 

 both zygotes and blasts from the gnat. 



JOSEPH BERTRAND. 



AMONG the heavy losses which science has suffered 

 -^"^ during the past few months, few will be the subject 

 of such universal regret as the death, on April 3, of M. 

 Joseph Bertrand. The loss will be felt, not only by 

 mathematicians, but also by the great body of scientific 

 men with whom Bertrand was brought into contact in 

 his capacity of life-secretary of the Paris Academy of 

 Sciences. 



Joseph Bertrand was born at Paris in 1823, and at an 

 early age commenced his mathematical studies under the 

 guidance of his father, who had been a pupil of the Ecole 

 Polytechnique. Subsequently Bertrand entered the 

 College de St. Louis, and at the age of eleven he suc- 

 ceeded in passing the examination for entrance into the 

 Ecole Polytechnique, although it was not till six years 

 later that he actually entered the college, when he headed 

 the list of candidates. As a boy, Bertrand would nowa- 

 days be styled an " infant prodigy," by analogy with the 

 youthful musicians who created such 2i furore at London 

 concerts a few years ago ; and it is interesting to learn 

 from M. Maurice Levy that this title {enfant prodige) 

 was actually bestowed on him by the scientific men who 

 welcomed Joseph as a young colleague at an early stage 

 of his existence. The analogy between music and mathe- 

 matics seems, moreover, to have suggested itself to M. 

 Jules Lemaitre, Director of the French Academy, who 

 remarks that such precocity of genius is sometimes found 

 in mathematics and in music, but is never seen in litera- 

 ture. We find Bertrand publishing a paper on the theory 

 of electricity in 1839, when he must have been about 

 sixteen years old, and it is hardly surprising in view of 

 this to learn that his precocity amazed his masters. In 



1 84 1 he wrote papers on indeterminate forms, Jacobi's 

 theorem and differential equations, and from that time 

 onward he was fairly launched on his career as a writer 

 of mathematical papers, his output being five papers in 



1842 and seven in 1843. But whereas most of the young 

 w^wixz'aS.debutatits., to whom reference has just been made, 

 have enjoyed only ephemeral reputations, and have ex- 

 hausted their energies in their premature efforts to an 

 extent which must have prejudiced their future careers, 

 Bertrand succeeded in achieving all that was predicted 

 of him ; he showed no diminution of energy in advancing 

 years, and, moreover, to judge from all accounts, he 

 developed into a good man of business, a quality which 

 is commonly regarded by " the general public " as incom- 

 patible with being a genius. 



In 1842 he had a narrow escape from being killed 

 in a railway accident near Meudon. In company with 

 his brother, Alexandre Bertrand, now distinguished as an 

 archaeologist, he had gone to Versailles to see the foun- 

 tains, and on the return journey the accident occurred in 

 which Admiral Dumont d'Erville was killed. Both of 

 the Bertrand brothers suffered, Joseph losing the bridge 

 of his nose — a misfortune which disfigured him for life-— 

 while Alexandre's leg was fractured. Joseph rescued his 

 brother by dragging him through "the skylight," the 

 carriage doors being locked. A few months later he 



