264 



SCIENCE 



[N. S. Vol. XXXVI. No. 922 



regards the movement of the blood' — " motion 

 as it were in a circle." This phrase was of 

 course written in Latin as " an motionem 

 quandam quasi in circulo haberet " ; it forms 

 part of the sentence thus translated: 



I began to think whether there might not be 

 motion (or a movement), as it were, in a circle. 

 Now this I afterwards found to be true. 



Later in the same chapter (VIII. of the 

 " De Motu ") he writes : 



This motion we may be allowed to call circular 

 (Quern motum eircularem eo pacto nominare licet.) 



•The establishing of the fact of the circula- 

 tion of the blood was absolutely essential to 

 the creation of physiology; modern physiology 

 has, indeed, arisen from this one fact, and the 

 fact received its name — circulation — ^from the 

 well-chosen phrase " circular motion." The 

 phrases " circle " and " circular " of 1628 be- 

 came in due time part of the language of 

 physiology; and the circulation of the blood 

 which was a phrase and an inference in 1628 

 became a visible demonstration in 1660. For 

 it is a fact, one of the most pathetic facts in 

 the history of biology, that Harvey died with- 

 out ever having seen the blood moving as he 

 knew so well it did, for he died in 1657, three 

 years before Marcellus Malpighius — the man 

 born in the year the " De Motu " was, 1628 — 

 saw the blood of the living capillaries of the 

 transparent lung of the frog. Thirty-two years 

 separated the metaphor from the demonstra- 

 tion, the prophecy from the fulfilment. Had 

 Harvey lived three years longer, he could have 

 seen with his ovm eyes that what he had 

 prophesied was correct, he could have been 

 shown as an actuality what his reason had 

 discovered as a magnificent inference, the 

 most magnificent inference ever made in the 

 realm of the living. 



The next example we may take from physi- 

 ological chemistry and from that new depart- 

 ment of it called " internal secretion." Until 

 comparatively recently, the function of the 

 two small yellow bodies situated near or on 

 the kidneys — adrenals or suprarenals — was 

 entirely unknown and barely even speculated 

 upon. In 1855 Dr. Addison, of Guy's Hos- 

 pital, London, described a disease, since named 



after him, in which the patient suffered from 

 extreme weakness both of muscles and of 

 heart, and after death was found to have had 

 his suprarenal bodies degenerated usually 

 through a tubercular lesion. Physiologists 

 very properly assumed that the explanation of 

 this was that in health the suprarenal bodies 

 produced something which, gaining access to 

 the blood, was carried to all parts of the body 

 and maintained the efficiency or tone of the 

 body-muscles and those of the heart and blood- 

 vessels as well. This something was appar- 

 ently absent from the blood in Addison's dis- 

 ease. This something remained undiscovered 

 until 1895, when watery extracts of the supra- 

 renals were made and injected into the veins 

 of a living animal. The result of this was a 

 surprising increase in the tone of the animal's 

 heart and small arteries so that its blood-pres- 

 sure rose greatly. Something was clearly con- 

 tained in the suprarenal extract which had 

 powerful physiological effects: let it be called 

 " adrenalin." But it is one thing to name a 

 hypothetical substance and another thing to 

 isolate a real one. In this case, however, the 

 hypothetical substance was a real one, so that 

 after some years of work between 1897 and 

 1904, the physiological chemists succeeded in 

 separating from the glands a substance in a 

 state of purity which had aU the properties 

 possessed by an extract of the suprarenals. 

 Adi-enalin was for the first time isolated about 

 forty-five years after its existence had been 

 surmised. So perfectly had the chemical some- 

 thing that maintains the tone of heart and 

 blood-vessels been isolated, that its constitu- 

 tion became so well known that the final tri- 

 umph of making adrenalin synthetically was 

 net long delayed. In 1904 it was made syn- 

 thetically in Germany, and in the following 

 year in England, so that within fifty years of 

 its suspected existence, adrenalin, with all the 

 properties of the natural material, was seen 

 and handled as a pure, crystalline chemical 

 substance of composition so well known that 

 its structural formula could be written and a 

 name denoting it laid before those capable of 

 understanding it (di-oxyphenol-methyl-amino- 



