September i6, 1897] 



NATURE 



473 



Dr. G. Granville Bantock; a Ring-tailed Coati i^Nastia rtifa), 

 a Kinkajou (Cercoleptes caudivolvulus) from South America, 

 deposited ; an Indian Civet ( Viverricula inalaccensis) from 

 India, a Chilian Sea Eagle {Geranoaeiiis melanoleucus) from 

 South America, purchased ; a Patagonian Cavy {Dolichotis 

 patackonica), born in the Gardens. 



OUR AS TRONOMICAL COL UMN. 

 The Disintegration of Comets. — If a comet is regarded 

 as a swarm of meteorites, a priori considerations point to disin- 

 tegration as its ultimate fate. Schiaparelli and Bredichin have j 

 familiarised astronomers with this fact, and the Great Comet of l 

 1882, as well as Brooks' Comet of 1889, were visible examples | 

 of the way in which cometary members of the solar system 

 break up in their old age. M. M. O. Callandreau has a short 

 article in the Bulletin Astroitoviique (September) upon this dis- I 

 integrating tendency, and also upon the relation of Jupiter to 

 comets of short period. The two subjects are very closely 

 related, for there is evidence that individual orbits in the groups | 

 of comets of short period in the neighbourhood of Jupiter \ 

 have been produced by a process of separation. What M. Cal- ! 

 landreau has done is to estimate, in a general manner, the ; 

 influence the trajectory described by the head of a comet has 

 upon di.sintegration, and to determine the extent of the sphere of ' 

 stability at different points of the orbit both when the sun's 

 attraction is considered alone, and when it is considered 

 with the action of Jupiter. The subject is dealt with entirely 

 from a dynamical point of view, no account being taken of the 

 influence of thermal radiation from the sun or of the apparent 

 force of repulsion exercised by the sun upon cometary 

 material. A comet is considered as a spherical swarm of par- ; 

 tides, and the density of the swarm is either taken as uniform : 

 or varying uniformly with distances from the centre. It | 

 appears that the elliptical form of an orbit favours disintegration. ! 

 The following consequences follow from equations obtained by ! 

 considering the sun's action alone : (i) When the distance of the 

 nucleus remains constant, the extent of the sphere of stability j 

 increases with increase of velocity. (2) The relation of the | 

 radii of the spheres of stability at aphelion and perihelion is : 



approximately equal to V^~\ > where e' is the eccentricity of i 



the orbit. As to the combined influence of the sun and | 

 Jupiter, it appears that if a comet gets within the Jovian sphere | 

 of attraction, the radius of which is 0*3 the radius of the j 

 earth's orbit, the disintegrating power upon the comet when 

 near aphelion is equivalent to that of the sun upon a comet 

 when at a perihelion distance of 0*58. 



Forecast of the Nove.mber Meteor Shower.— Mr. VV. F. 

 Denning continues, in the Observatory, an interesting paper upon 

 " The Great Meteoric Shower of November," and predicts the 

 probable character of the showers which will occur during the 

 next six or seven years. His forecast for this year's display is 

 as follows : — " In 1864 (two years before the max. of 1866), a 

 grand display of meteors was witnessed from the deck of a ship 

 off Malta on the morning of November 13, and meteors were 

 conspicuously numerous on the same morning in America. We 

 are therefore entitled to expect a pretty abundant display in 

 1897, and should it prove a return of the same group which sup- 

 plied the meteors of 1864, it will probably return in the morning 

 hours of November 14. But the earth will intersect a point of 

 the meteoric orbit rather further in advance of the comet than it 

 did in 1864, and so the exhibition of 1897 is not likely to equal 

 the former, unless, indeed, the richer part of the stream has 

 lengthened out in the interval of thirty-three years, which is 

 quite possible. The really dense part of the system which 

 furnished the brilliant European display of 1866 (max. Nov. 13, 

 I3h. lom.), and the equally imposing American shower of 1867 

 (max. Nov. 13, 22ih.), is not likely to be visible in England, 

 as the earth will be centrally involved with it on the 14th at 

 midday. In America something of it may possibly be seen just 

 before sunrise on the 14th. The moon will be full on the 

 morning of the 9lh, and will therefore be gibbous on the 14th, 

 rising at 7h. 55m. at Greenwich, and being visible in Gemini 

 during the whole night afterwards. The prospects are there- 

 fore by no means good, but a close watch should be maintained 

 on the mornings of the 14th, 15th, and i6th ; for if the at- 

 mosphere be clear, meteors will sure to be frequent, and fine 

 ones may appear every now and then." 



THE RELATIONSHIP OF PHYSIOLOGY, 

 PHARMACOLOGY, PATHOLOGY, AND 

 PRACTICAL MEDICINE} 



T^HE desire for knowledge which is common to the lower 

 ■*■ animals and man, savage or civilised, and has induced 

 members of this Congress to come from the ends of the earth in 

 order to gain information, must have led primitive man from the 

 earliest times to study the great problems of physiology, the 

 nature of life, of growth, of reproduction, and of death, as well 

 as to notice the connection of the latter with mechanical 

 injuries, such as the wounds inflicted by clubs and spears or by 

 the teeth and claws of wild beasts. 



Next to the problems of physiology come those of pharma- 

 cology, by which I mean the poisonous or remedial action of 

 various substances, mineral, vegetable, or animal. A knowledge 

 of this subject is found even amongst the lowest savages, and is 

 of the greatest use to them, for it enables them, on the one hand, 

 to avoid eating things which may cause discomfort, pain, or 

 death, and, on the other, to obtain food by poisoning waters and 

 thus catching fish, or by poisoning their arrows to kill game 

 which would otherwise escape. Closely associated with the 

 knowledge of the poisonous is that of the curative powers of 

 herbs, and it is possessed by animals as well as man, for cows 

 avoid noxious plants, and dogs will every now and again eat 

 grass apparently as medicine. Primitive peoples use various 

 substances as remedies in disease, with more or less success, and 

 one of the most extraordinary points in their practice is that 

 they seem to some extent to have forestalled the newest re- 

 searches on venins, anti-venins, and organotherapy, for in 

 Africa the Bushmen are accustomed to drink the poison of 

 venomous snakes as a prophylactic against their bite, and the 

 Hausas prevent hydrophodia by killing the mad dog and making 

 the man it has bitten eat its liver. 



The occurrence of death from wounds or poison is intelligible 

 even to a savage, but when illness and death occur independently 

 of these, men naturally attribute them to invisible powers. Thus 

 the Dyaks of Borneo ascribe sickness to wounds from invisible 

 spears weilded by invisible spirits, and during an epidemic of 

 disease in the Middle Ages the cry often arose that the wells 

 had been poisoned. These crude ideas contain germs of truth, 

 and when we look at Prof. Metschnikoff's drawings of a Daphnia 

 attacked by a Monospora we seem to recognise the invisible 

 darts of the Dyaks, while during an epidemic of typhoid fever 

 we have often to acknowledge that our wells have been poisoned 

 by bacilli. 



It is impossible to trace the steps by which the crude ideas 

 of savage peoples regarding physiology, pharmacology, and 

 pathology have grown into definite sciences, nor even to indicate 

 the most important landmarks, though we naturally think of 

 the names of Alkmaon, Galen, and Harvey in physiology ; 

 of Nicander, Magendie, and Bernard in pharmacology ; and 

 of Morgagni, Virchow, and Pasteur in pathology. During 

 this century these three sciences have developed with almost 

 incredible rapidity, a complete knowledge of them is enough to 

 tax severely the most retentive memory, and it is almost im- 

 possible for any individual to keep up with the advance of all 

 three of them. 



But just as the whole subject of astronomy became suddenly- 

 simplified by a change of standpoint at the very time when 

 cycles and epi-cycles became most bewildering, so at the ver)- 

 time when these three sciences are becoming most complex and 

 diverse they appear to be tending to unification and simplifica- 

 tion. Pathology, for example, is now becoming to a great 

 extent a branch of pharmacology, for while a few years ago its 

 chief object was to discover, examine, and classify the microbes 

 which give rise to disease, it is now striving rather to discover 

 the nature and actions of the ferments and poisons which they 

 form, and by which they are able to cause disease and death in 

 the animals they attack. Pharmacological investigation instead 

 of being confined to the alkaloids and other poisons formed by 

 higher plants has now extended to those formed by microscopic 

 plants or microbes, and thus comes to include a great part of 

 pathology. 



In the same way, though pharmacology is a branch of 

 physiology, inasmuch as it deals with the phenomena of life as 

 modified by drugs, yet physiology may, to a certain extent, be 



1 An address delivered at the Twelfth International Medical Congress at 

 Moscow, on August 19, by Dr. T. Lauder Brunton, F.R.S. 



NO. I455» VOL. 56] 



