412 NATURAL SCIENCE. Dec. 



modern developments of Harvey's work, and here it is to be observed 

 tliat the pure physiologist is to the front. The specialisation 

 demanded by modern science renders this imperative, and all that 

 can be asked of the practitioner is that he shall keep himself abreast 

 of the discoveries of the physiologist and learn to apply them in the 

 treatment of disease. It is the intelligent application of the discoveries 

 of pure science which forms the field in which clinical medicine and 

 surgery have made and will make their most rapid advances, and it 

 is in this field that a scientific training and habit of mind will be of 

 most value to the practitioner. 



Antitoxins. 

 The latest application of pure science to practical medicine con- 

 sists in so-called " serum therapeutics." Although diphtheria antitoxin 

 is still on trial as a means of practical treatment, there can be no 

 doubt that its discovery is an immense advance in medicine. Chemical 

 theories of immunity now bid fair to oust from the field the theories 

 based on the doctrine of phagocytosis. " Fiir bose Gifte, Gegengift," 

 sings Brangave, in ' Tristan und Isolde,' and it is a good motto for 

 the modern pathologist. There is already strong evidence that the 

 ' Gegengift,' manufactured in the animal body as the result of a non- 

 fatal attack of tetanus or diphtheria, can be used with effect in the 

 treatment of the same diseases in man ; but some time must elapse 

 before good statistical evidence is forthcoming as to the effects of the 

 diphtheria antitoxin. And for this reason. It is a usual custom in 

 this country to regard as diphtheria all cases of membranous sore 

 throat, nor can it be doubted that it is a wise practice to treat them as 

 such. But statistics are in this way largely invalidated. Conclusive proof 

 of the diphtheritic nature of a sore throat can be obtained only by the 

 recognition of the characteristic diphtheria bacillus, and it is, perhaps, 

 chiefly on this account that the foreign statistics of diphtheria mortality 

 appear so much higher than ours, since only cases in which this 

 evidence is present are admitted into the category of true diphtheria. 

 When this source of fallacy is removed in this country by a systematic 

 bacteriological examination of all cases of suspected diphtheria, we shall 

 be in a position to estimate at its true value this latest development of 

 science in the treatment of a hitherto intractable disease. 



An Electrical Theory of Vision. 

 An interesting communication, brought before the British Asso- 

 ciation, and as yet unnoticed in our columns, was Professor O. J. 

 Lodge's suggested electrical theory of vision. This was preceded 

 and introduced by experiments illustrating Clerk Maxwell's theory of 

 light. The necessary electrical radiations were obtained from a 

 sphere charged from an induction coil; for their detection an arrange- 

 ment of loosely-packed particles was employed. These, under the 

 influence of the surgings of the electrical radiations, attracted one 



