EERLICE'S SPECIFIC THERAPEUTICS 211 



sometimes accompany ability of the highest order. As a student, Ehr- 

 lich bore out President Eliofs theory that any young man who has real 

 capacity usually has a better inkling of its extent, if not of its limita- 

 tions, than his elders can teach him. Age and experience may per- 

 haps indicate what youth can't do, but they have no power of predicting 

 what it can do. It is related that when Robert Koch was once visiting 

 the Breslau laboratories, a young student working at a table covered 

 with staining materials was pointed out to him, with the remark: 

 " There is our little Ehrlich. He is a first-rate stainer of tissues, but 

 he will never pass his examinations."' The prediction was true. Ehr- 

 lich got his degree by courtesy, on the strength of his well-known dis- 

 coveries in the histology of the blood ; but doubtless his academic spon- 

 sors serenely followed the example of Kant, who, in lecturing, addressed 

 himself to students of mean average intellect only, on the assumption 

 that the blockheads were beyond human help, while the geniuses could 

 take care of themselves. The young Ehrlich easily made himself 

 recognized as a true-born scientific genius, but his example will scarcely 

 save less careful or more luckless students from being plucked at their 

 final examinations. 



Although for practical use, Ehrlich's researches in synthetic chem- 

 istry rank near to those of Emil Fischer, he is a true Asclepiad, and 

 his principal aim has always been to improve the diagnosis and treat- 

 ment of disease. Nearly all his results are of fundamental importance 

 for actual medicine and they are a long list. We can imagine some 

 awarder of a Copley medal or Xobel prize recounting them : First, the 

 improved methods of drying and fixing blood smears by heat and the 

 staining methods which have become such a feature in recent diagnosis, 

 notably the tri-acid stain, the fuchsine stain for tubercle bacilli and the 

 method of intra-vital staining, the first step towards getting in touch 

 with what is going on inside the living cell; then his discovery of five 

 new constituents of the blood which have become basic principles in 

 modem diagnosis; his important study of the oxygen requirements of 

 a living organism; his diazo-test for the urine in typhoid fever; his 

 demonstration that animals can be quantitatively immunized against 

 the effects of vegetable poisons like abrin and ricin, as well as against 

 the toxins of vegetable parasites; and conversely, that animal parasites 

 have the power of immunizing themselves and their descendants against 

 the action of drugs ; his improvement of Behring's diphtheria antitoxin 

 and his establishment of an international standard of purity for the 

 same; his side chain theory of immunity, which led at once to such 

 brilliant results as the TVassermann method of serodiagnosis and (in 

 medical jurisprudence) to the precipitin tests for blood-stains (Bordet- 

 Uhlenhuth) and the cobra-venom test for insanity (Much-Holtzmann) ; 



*The anecdote is given by the late Dr. Christian A. Herter in Jour. Am. 

 Med. Assoc, Chicago, 1910, LIV., 428. 



