May 25, 1893] 



NATURE 



S7 



produce, of causing the changes which characterise the particular 

 disease. 



I show you here photographs of a variety of such pathogenic 

 bacteria, and you will see from them that both as regards the 

 manner of distribution of these bacteria in the tissues of the 

 infected individuals as also in their morphological and biological 

 characters in artificial cultures, most of them are sufficiently 

 distinguished from one another and from other non-pathogenie 

 bacteria. In considering the general action of pathogenic l)ac- 

 teria we find that they may be grouped into {a) such 

 as are entirely, so far as our knowledge at present goes, 

 dependent on the living body of man or animals ; these are en- 

 dogenic bacteria or true parasites, for they do not appear to lead 

 .nn existence independent of the living body : when, therefore, 

 infection by them takes place, it takes place by direct trans- 

 ference from an infected individual to a new one ; this is so in 

 small-pox, in vaccinia, and in hydrophobia ; (b) a second group 

 comprises those which are capable besides a parasitic life, i.e. 

 growing and multiplying within the animal body, to lead also an 

 existence independent of the animal body ; that is to say, they, 

 like many other non-pathogenic bacteria, are capable of thriv- 

 ing in suitable materials in the outside world ; such are anthrax 

 and fowl cholera, asiatic cholera and typhoid fever, tetanus and 

 diphtheria, and others. But also amongst these some can lead 

 such an " ectogenic " life comparatively easily, while others do 

 so only in a restricted sense ; while, for instance, anthrax, 

 tetanus, typhoid fever can lead such ectogenic life easily, i.e. 

 growing and multiplying outside the animal body ; others, like 

 tubercle and glanders, do so only to a very small extent. The 

 former are obviously the more dangerous to man and animals on 

 account of their more ready distribution than the latter, of which 

 the ectogenic existence is considerably restricted by various con- 

 ditions, e.g. they require higher temperatures to grow at, they 

 require a much more specialised nutritive medium than is 

 generally attainable by them. 



Time does not permit me to show you in detail the many and 

 wonderful results obtained within a comparatively short recent 

 period by a large number of workers, as regards the identifica- 

 tion of many of the pathogenic bacteria, their habits of life, 

 their mode of spread and infection ; the way in which their ac- 

 tion can be attenuated, their effects weakened, and such weak- 

 ened cultures used for protective inoculations ; the brilliant 

 results achieved by Pasteur and many others in these protective 

 and curative inoculations against anthrax, against fowl cholera, 

 against tubercle, against hydrophobia, against tetanus and other 

 diseases. But I will ask you to bear in mind that almost the 

 entire study of bacteria, the exact methods first introduced by 

 Koch and now universally used not only in regard to patho- 

 genic bacteria, but in all other branches of bacteriology ; the 

 exact knowledge that we possess of some of the most important 

 branches of hygiene : as the knowledge of the exact nature of 

 contagium, its mode of spread, the means of disinfection, the 

 methods of protective inoculation, and a hundred and one other 

 important points have been the result of, and gained by, experi- 

 ment on animals. Amongst the wilderness of misery, cruelty, 

 and death inflicted by mankind on animals for gain, for sport, 

 pleasure, and other similar objecls, to decry, as some do, the 

 use of a comparatively few animals for the sake of gaining 

 knowledge of the most important and complex phenomen.i of 

 life and of disease, and of securing power to apply this know- 

 ledge in the interest not only of mankind, but of the animals 

 themselves, is apt to make one remember the words: "Ye 

 blind guides ! which strain at a gnat and swallow a camel," 

 or the words, "Thou hypocrite ! cast out first the beam out 

 of thine own eye, and then shalt thou see clearly to pull out the 

 mote that is in thy brother's eye." 



SURGERY AND SUPERSTITION. 



'T'O those unversed in the history of surgery it may come as a 

 surprise that many of the appliances commonly regarded 

 as the inventions of yesterday, are but the perfected forms of 

 implements long in use. It is astonishing to find amongst the 

 small bronzes of the National Museum at Naples, bistouries, 

 forceps, cupping-vessels, trochars for lapping, bi-valvular and 

 tri-valvular specula, an elevator for raising depressed portions 

 of the skull, and other instruments of advanced construction 

 which differ but little from their modern congeners. The in- 

 mention of such instruments, and the skill displayed in their 



NO. 1230, VOL. 48] 



construction, presupposes a long period of surgical practice. 

 We find, accordingly, that four hundred years before our era, 

 Hippocrates was performing numerous operations bold to the 

 verge of recklessness. Thus he was accustomed to employ the 

 trepan not only in depression of the skull or for similar 

 accidents, but also in cases of headache and other affections to 

 which, according to our ideas, the process was singularly inap- 

 plicable. Strangely enough, the Montenegrins are, or recently 

 were, accustomed to get themselves trepanned for similar 

 trifling ailments, and it is probable that in both instances the 

 procedure was but the surviving custom of primeval ages. 

 That such operations were then performed Dr. Robert Munro, 

 in his admirable article upon prehistoric trepanning in the 

 February number of the Fortnightly Rri.ne;u, conclusively shows. 

 His paper records a strange blending of the sciences of medicine 

 and theology in their initial stages ; for, whilst he makes it 

 clear that during the neolithic period a surgical operation was 

 practised (chiefly on children) which consisted in making an 

 opening through the skull for the treatment of certain internal 

 maladies, he renders it equally evident ihat the skulls of those 

 individuals who survived the ordeal were considered as 

 possessed of particular mystic properties. And he shows that 

 when such individuals died fragments were often cut from their 

 skulls, which were used as amulets, a preference being given to 

 such as were cut from the margin of the cicatrised opening. 

 The discovery arose as follows. In the year 1873 Dr. 

 Prunieres exhibited to the French Association for the Advance- 

 ment of Science an oval cut from a human parietal bone, which 

 he had discovered in a dolmen near Marvejols, embedded in a 

 skull to which it had not originally belonged. His suggestion 

 that it was an amulet was confirmed on the discovery of similar 

 fragments of bone grooved or perforated to facilitate suspension. 

 When Dr. Prunieres's collection was examined by Dr. Paul 

 Broca he pointed out that that portion of the margin of the 

 bone which had been described as "polished" owed its texture 

 to cicatricial deposits in the living body, and that, where these 

 were wanting, death had ensued before the pathological action 

 was set up, or the operation had been post mortem. 



These discoveries led to widespread investigation, and to the 

 production of trepanned skulls from Peru, from North America, 

 and from nearly every country of Europe. These were not 

 restricted to any particular race or period, but ranged from the 

 earliest neolithic age to historic times, and included skulls of 

 dolichocephalic and brachycephalic types. 



The method of conducting the operation appears to have been 

 to gradually scrape the skull with a sharp flint, though there is 

 occasional evidence of its use in asawingmanner such as obtained 

 when the ruder implement was superseded by one of metal. The 

 process was almost exclusively practised upon children, probably 

 on account ofthefacilitywithwhichit could then be accomplished, 

 and possibly also as an early precaution against those evils for 

 which it was esteemed a prophylactic. What the dreaded evils 

 were was suggested by Dr. Broca, who, whilst he believed that the 

 operation was primarily conducted for therapeutic purposes, saw 

 behind these the apprehension of a supernatural or demoniacal 

 influence. Readers of Lenormant's " Chaldean Magic" will 

 remember "the wicked demon which seizes the body, which 

 disturbs the body," and that " the disease of the forehead pro- 

 ceeds from the infernal regions, it is come from the dwelling of 

 the lord of the abyss." With such an antiquated record before 

 us it is, therefore, hy no means an extravagant theory to broach, 

 as Dr. Broca has done, that many of the convulsions of child- 

 hood, which disappear in adult life, were regarded as the result 

 of demoniacal possession. This being granted, what more 

 natural than to assist the escape of the imprisoned spirit by 

 boiing a hole in the skull which formed his prison. When a 

 patient survived the operation he became a living witness to the 

 conquest of a fiend, and it is comprehensible that a fragment of 

 his skull taken after death from the very aperture which had 

 furnished the exit would constitute a powerful talisman. 

 Chaldean demons, as we know, fled from representatives of their 

 own hideous forms, and, if they were so sensitive on the score 

 of personal appearance, others may have dreaded with equal 

 keenness the tangible record of a previous defeat. It is certain 

 that to cranial bones medicinal properties were ascribed, a belief 

 in the efficacy of which persisted to the dawn of the eighteenth 

 century ; whilst, in recent years, such osseous relics were worn 

 by aged Italians as charms against epilepsy and other nervous 

 diseases. When once the dogma was promulgated that sanctity 

 and a perforated skull were correlated, fond relatives might bore 



