6o6 



NATURE 



[January 27, 19 16 



many devoted workers, and made great advances; 

 but during the past one hundred years it is biological 

 science that has contributed most to the well-being 

 of humanity. The new methods of transportation and 

 of manufacturing by the aid of machinery with steam 

 as motive power were products of applied physics. 

 So were the great works of civil and mechanical 

 engineering. The improved agriculture of the last 

 half of the nineteenth century was partly due to new 

 tools and machinery, and partly to new applications 

 of chemical knowledge. Latterly biological science has 

 helped the farmer very much to raise better crops and 

 animals, and to protect his products from vegetable 

 and animal pests. 



While the industrial and social changes which 

 applied physics and chemistry made possible unques- 

 tionably improved the general condition of mankind as 

 regards bodily comfort, security against natural cata- 

 strophes, longevity, and an increased sense of mutual 

 support and community interest through the vast 

 improvement in the means of communication, these 

 changes have all been indirect influences on human 

 well-being and happiness, and with the good they 

 brought much evil was mixed. Thus, the factory 

 system, the congestion of population, and the noise 

 and turmoil of city life are grave evils accompanying 

 the advantages which applied physics and chemistry 

 have created and diffused. The fruits of the biological 

 sciences — botany, zoology, physiology, and bio- 

 chemistry, applied to curative medicine and surgery 

 and to preventive medicine and sanitation — have been 

 direct contributions to human welfare; because they 

 have provided defences against disease, premature 

 death, and individual and family distress and suffering. 

 The beneficent applications of biological science, unlike 

 most of the large results of applied chemistry and 

 physics, take effect in the field of human affections and 

 family experiences, make life less anxious and more 

 enjoyable for multitudes of human beings, mitigate 

 or abolish ancient agonies and dreads of the race, 

 and promise for it a happier future. 



The career of Pasteur illustrates admirably the pass- 

 ing of the centre of beneficent scientific research from 

 chemistry and physics to biological science. Pasteur's 

 first researches were crystallographic ; whence he 

 passed to the study of molecular dissymmetry, the 

 material of his researches being, however, organic. 

 He was first professor of physics and then professor 

 of chemistry. His interest in certain tartrates led 

 him naturally, though partly by accident, to a study 

 of fermentation. His zealous discharge of his duties 

 as dean of a faculty of sciences at Lille, a manufac- 

 turing centre, led to his study of beetroot juice, fer- 

 mented in order to produce alcohol. Thereafter Pas- 

 teur's researches were biological, although he had had 

 no training as either naturalist or physician. He began 

 at the foundation by disproving the doctrine of spon- 

 taneous generation. One of his earliest conclusions 

 was that " gases, fluids, electricity, magnetism, ozone, 

 things known or things occult, there is nothing in the 

 air that is conditional to life except the germs it 

 carries." Of his earliest results from experiments on 

 admitting pure air to flasks containing putrescible 

 infusions he wrote : " It seems to me that it can be 

 affirmed that the dusts suspended in atmospheric air 

 are the exclusive origin, the necessary condition of life 

 in infusions " ; and in the same paper he made the 

 pregnant remark, "What would be most desirable 

 would be to push those studies far enough to prepare 

 the road for serious research into the region of various 

 diseases." He lived to push his studies into the causes 

 of the silkworm disease, of a cholera which came 

 from Egypt into France, of the plant diseases affecting 

 the manufacture of wine and of beer, of the splenic 

 fever, of the chicken-cholera, and of rabies ; and he 

 NO. 2413, VOL. 961 



and his followers invented successful treatment for 

 those diseases, and for the treatment of typhoid fever 

 and diphtheria. 



The germ and parasite theory of disease led the way 

 in serum therapy, and established both the philosophy 

 and the practice of the new medicine and surgery of 

 the past thirty-five years. Starting with a sound 

 knowledge of chemistry and physics, and having early 

 acquired a habit of utmost accuracy in observing and 

 reasoning, Pasteur passed over into biological science 

 by the time he was thirty-two years of age, and became 

 the most suggestive and productive inventor and pro- 

 moter in applied biology that has ever lived. His 

 career illustrates conspicuously the general truth that 

 the sciences most serviceable to mankind during the 

 past sixty years have been the biological sciences. In 

 a letter to his father in i860, when his inquiries were 

 opening new vistas in physiology, Pasteur wrote :- 

 " God grant that by my persevering labours I may 

 bring a little stone to the frail and ill-assured edifice 

 of our knowledge of those deep mysteries of life and 

 death, where all our intellects have so lamentably 

 failed." That prayer was granted. 



Let us review in a summary way the fruits of 

 applied biological science since the nineteenth century 

 opened. 



The first invention, vaccination against smallpox, 

 long antedated the later studies of germs, parasites, 

 the routes of disease from one human being to another 

 through insects and other animals, and the theory and 

 practice of immunity. Vaccination, the invention of a 

 country doctor who practised in a dairy district, was a 

 momentous discovery in immunity from a fatal and 

 disfiguring disease, which was frequently epidemic, 

 the immunity being procured by causing in the human 

 body another disease very seldom fatal and not at all 

 disfiguring. The favourable reception and rapid appli- 

 cation of Jenner's discovery were due to the fact that 

 many persons at that time protected themselves against 

 the frequent and terrible epidemics of smallpox by 

 being inoculated with smallpox itself. So soon as it 

 was proved that cowpox gave immunity in almost all 

 cases against smallpox, inoculation with cowpox came 

 rapidly into use ; because inoculated cowpox proved to 

 be, as one of Jenner's contemporaries remarked, "a 

 pleasanter, shorter, and infinitely more safe disease I 

 than inoculated smallpox." The relief of civilised 

 mankind from the terrible recurrent epidemics of 

 smallpox is one of the greatest benefits that the pro- 

 fession of medicine has conferred on the human race. 



From biological studies largely on microscopic 

 organisms — protozoa, bacteria, and parasitic growths 

 — the means of communication from one human being 

 'to another, or from an animal to man, of dysentery, 

 cholera, typhoid fever, typhus fever, puerperal fever, 

 bubonic plague, diphtheria, tuberculosis, cerebro-spinal 

 meningitis, syphilis, gonorrhoea, sleeping sickness, 

 yellow fever, malaria, and hook-worm disease, have all 

 been brought to light. Means of preventing or restrict- 

 ing the spread of these diseases — with the exception 

 of cerebro-spinal meningitis — have been invented, and 

 for most of them improved methods of treatment have 

 been devised. Much has also been learnt about infan- 

 tile paralysis, and something about cancer. The 

 whole subject of toxins and antitoxins has been de- 

 veloped with wonderfully beneficent results. 



It is really impossible to describe or appreciate the 

 alleviations and preventions of human misery included 

 in this list of the fruits of applied biological science. 

 Some of the diseases mentioned were within a few 

 years familiar household terrors in the most civilised 

 countries, others from time to time destroyed in recur- 

 ring epidemics large portions of the population in many 

 parts of the world. They terrorised families and 



